sustainability
Review

Future Design: Bequeathing Sustainable Natural
Environments and Sustainable Societies toFuture Generations
Tatsuyoshi Saijo 1,2
12

Research Institute for Humanity and Nature, Inter-University Research Institute Corporation National
Institutes for the Humanities, Kyoto 603-8047, Japan
Research Institute for Future Design, Kochi University of Technology, Kochi 780-8515, Japan;
tatsuyoshisaijo@gmail.com

Received: 28 June 2020; Accepted: 27 July 2020; Published: 11 August 2020


Abstract: “Future Design,” a new movement among Japanese researchers and stakeholders, asks thefollowing question: What types of social systems are necessary if we are to leave future generations
sustainable environments and societies? Looking at the human activity impact on the global
environment and society, I ask: Why is this society we live in generating a series of future failuresthat will cost future generations so much? I then argue that the source of such a society could be
liberalism and that the market and democracy derived from it will not help avoid these future failures.
To achieve this, one must design social systems that activate a human trait called futurability, where
people experience an increase in happiness because of deciding and acting toward foregoing current
benefits to enrich future generations. One method to study these is by employing “imaginary future
generations”. Here, I present an overview of the theoretical background of this method, the resultsof relevant laboratory and field experiments, and the nature of relevant practical applications
implemented in cooperation with several local governments.
Keywords: future design; imaginary future generation; futurability; intergenerational sustainability
dilemma; time inconsistency problem

1. Introduction“Future Design” is a movement that studies the types of social systems that would ensuresustainable environments and societies for future generations. The human activity impact on the
global environment and society indicates that our society is generating a series of future failures such as
global warming, loss of biodiversity, and large amounts of outstanding debt in many countries thatwill severely influence future generations [1–5]. To find the reasons behind this behavior, I consider
human traits such as myopia, optimism, contrast, and sociality, where contrast is reflective of people’s
tendency to respond to relative changes rather than absolute values [6,7].
Due to myopia, optimism, and contrast, people do not consider the distant future, causing a“struggle of all against all” [8]. Classical liberalists such as Hobbes [8], Locke [9], and Rousseau [10]created a social contract in which this struggle is avoided, and people gain freedom, independence
and equity. However, I argue that the market and democracy derived from liberalism will not help
avoid future failures [11,12]. Future generations cannot participate in today’s markets and, hence,cannot express their willingness to preserve current resources. On the other hand, democracy ministers
primarily to the present generation and is not concerned with future generations.
Innovations continued throughout the Industrial Revolution, where large amounts of inexpensive,
seemingly limitless fossil fuels were used [13,14]. Together with social systems such as markets

Sustainability 2020, 12, 6467; doi:10.3390/su12166467

www.mdpi.com/journal/sustainability

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2 of 21and democracy, these factors are likely to have strengthened the human traits of contrast, myopia,
and optimism, while weakening sociality. In turn, changes in these traits transformed the market,
democracy, and innovation. This is likely what has created a society blindly focused on growth,
despite its leading to various future failures mentioned above [1–5].
If this is the case, the transformation of social institutions themselves should be a major challenge
for the first half of the 21st century. The various fields of social science have become fixated on
individual paradigms; an answer to the question of how to transform institutions for a sustainable
future has not yet been found. Nevertheless, the current mainstream approach is to coordinate andsynthesize knowledge from humanities, sciences, and social sciences, and then use this to understandhuman behavior, devise social systems, and solve various public problems.
Future Design (FD) takes the opposite position [11]. Traditional social science assumes that people’s
behavior, way of thinking, and nature do not easily change. However, these are transformed by social
institutions and their feedbacks. In other words, the market and democracy themselves shape theways in which we think and behave. To this end, in this study, we design various social mechanismsthat transform our way of thinking, and test their performance using knowledge from various fields.
FD focuses on activating a human trait called futurability, where people experience an increasein happiness because of deciding and acting to forego current benefits in order to enrich future
generations [11]. One method to study this is by employing “imaginary future generations”. Here,I present an overview of the theoretical background of this method, results of relevant laboratory andfield experiments, and the nature of relevant practical applications implemented in cooperation withseveral local governments.
Section 2 describes what has been done in this regard in the last several centuries. Section 3
contains an analysis of why we live in a society producing future failures and introduces the FD
approach. Section 4 focuses on the possibility of transformation in favor of a sustainable society.
The FD experiments that include imaginary future generations are described in Section 5. Section 6
outlines the justification for using imaginary future generations from a philosophical point of view.
In Section 7, FD’s practical applications that are underway in several towns, cities, and prefectures inJapan are described. In lieu of conclusions, Section 8 includes outstanding issues of FD.
2. What Is It That We Have Done?
The Covid-19 outbreak began in Wuhan, China, on 31 December 2019; the World HealthOrganization declared it a global pandemic on March 11, 2020 [15]. The peak dates of the first-wave
outbreaks were 12 February (China); 3 March (South Korea), 21 (Italy), 26 (Spain), 27 (Germany),
30 (Iran), and 31 (France); and 10 April (England), 11 (Japan), and 24 (USA) [16]. Covid-19 was rapidly
spread by air transport. Since 1950, passenger and cargo air traffic have expanded annually at a rateof approximately 5% and 6%, respectively [17,18]. Thus, they have doubled every 14 and 12 years,
respectively. The air passenger growth rate approached 6% per year during the 2010–19 decade.
Compared to the 1950s, the passenger traffic in 2019 was over 32 times larger. By contrast, the global
gross domestic product (GDP) has increased annually by less than 4% since 2000 [19]. Globalization
has been largely supported by fossil fuels. Air travel-related carbon dioxide emissions have doubled
between 1990 and 2016 [20,21]. Despite improvements in aircraft fuel efficiency and other factors,
these emissions increased at an average annual rate of approximately 3% from 1990 to 2016, reaching
5.2% during 2015–2016 [20].
Steffen et al. [1] demonstrated that indicators of the human activity impact on the global
environment (i.e., concentration of carbon dioxide, nitroxide and methane in the atmosphere, volume of
nitrogen influx into the oceans, and reduction of tropical forests) show that changes occurred at anaccelerating pace since the Industrial Revolution, especially during the second half of the 20th century.
Further, an accelerating change in indicators such as population, real GDP, use of fossil fuels andfertilizers, and number of automobiles has also been reported [1]. These (including the acceleration of
air the traffic growth described above) are trends known as the Great Acceleration.

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The planetary boundary concept proposed by Rockström et al. [2] identified nine domains
essential to maintain the comparatively stable Holocene environment that has been in place formore than 10,000 years. It also defined acceptable levels for those planetary boundaries. However,Rockström et al. [2] demonstrate that such acceptable levels have already been breached for climate,biodiversity, land systems (the proportion of forests lost), and cycles of biochemical substances suchas nitrogen and phosphorus. For example, the concentration of atmospheric carbon dioxide and theradiative forcing should be less than 350 ppmv and 1 Wm−2 , respectively, compared to their levels
before the Industrial Revolution. Both these indicators are beyond these levels already, increasing therisk of irreversible climate changes such as depleted polar ice caps, accelerated rise of oceanic levels,and sudden changes in the forestry and agricultural system [2,3]. Regarding this, Steffen et al. [3]mentioned the necessity of taking into account the time needed by society to react to early warning
signs. Furthermore, they [4] found that there is a risk that the Earth system could be irreversibly
pushed down a “Hothouse Earth” pathway despite the Paris Accord target being met.
Crutzen and Stoermer [22] and Crutzen [23] proposed that the Holocene age has ended already,and human beings pushed the Earth System into a new geological age—the Anthropocene. However,to the extent that human activity has indeed changed the Earth, this planetary boundary research canbe regarded as an evaluation of natural sciences since the Industrial Revolution.
Next, let us look at the relationship between the human development index (HDI) and per-capita
ecological footprint (EF) [24]. HDI measures the wellbeing achievements of a country, such as average
life expectancy, level of education, and per-capita income. The EF—a “sustainability” indicator—reveals
whether the country is living within its share of global means. HDI and EF are low for developing
countries and high for developed countries. Almost all countries progress from low to high HDIs andEFs, although they should aim for high HDI and low EF. The relationship between these two indexes
represents the link between scientific and social evaluations. When viewed in conjunction with theplanetary boundaries evaluation, it reveals that we are threatening our own continued existence.
Moreover, developed countries amassed large amounts of outstanding debt. According to theInternational Monetary Fund’s World Economic Outlook Database [14], the outstanding debt of Japan
is 2.37 times its GDP, and that of Italy, USA, and France, 1.35, 1.09, and 0.99 times, respectively,
their GDPs,. Increasing their existing debt further, governments spend massive amounts of money tocope with the current pandemic.
In other words, the current generation is maintaining wealth by exhausting the resources of future
generations. Regarding Japan’s public debt, for example, even a consumption tax that raises as much as
10 to 40% for the next 100 years would roughly decrease it by only 60% [25,26]. Would any generation
be capable of implementing such drastic measures?
3. Why Are We in this Situation, and What Will Happen Next?
Why is this society we live in producing future failures that will cost future generations heavily? One
major factor could be the social contract supported by Hobbes [7], Locke [8], Rousseau [9], and others,
as the source of liberalism [27]. By breaking the yoke of social classes and norms, ending the “struggleof all against all,” and creating a social contract, people gain freedom, independence, and equity.
Another factor might be the idea of mankind’s conquest of nature conceived by Bacon [28]. That is,he “argued for the human capacity to “master” or “control” nature” [27].
Sapolsky [5] identified three human traits underpinning the social system based upon liberalism.
The first is “contrast.” For example, our five senses react to changes rather than absolute values.
A sudden change may represent a risk; we naturally react (by default) to it, to increase our chance ofsurvival. For example, we react more to a change in volume—that is, to its differential value—than
to absolute volume. In other words, human beings react when external factors change. If owing to
the change in the parameters (external factors) within the objective function, the variable maximizing
the objective function ought to also shift, we can conclude that “contrast” expresses the optimality
principle of humans. Of course, “contrast” is not limited to a person’s five senses. For example,

Sustainability 2020, 12, 6467

4 of 21the human brain is said to react strongly to the body’s position relative to other people. For example,
in a group of people chased by a lion, a person does not need to be fast in absolute terms, but merely
faster than the slowest one.
The second human trait is “impulse.” It is not easy to resist eating something delicious laying
before us, for example. “The dopamine reward pathways in the human brain light up on brain-imaging
tests when we go for the impulsive immediate reward” [5]. In short, to increase the likelihoodof survival, the best thing to do when food was available was to eat it. Interpreted more broadly,
the impulse can be considered “myopia.”
The third trait is “sociality.” Human beings do not possess the physical abilities of other creatures.
We run slower than dogs (let alone horses!), our sense of smell is rather dull, and our eyesight not very
keen. For us to adapt better than other mammals and, indeed, to thrive, a deep understanding of ourrelationship with other people was required. For example, humans could hunt big animals only ingroups, not alone. By cooperating with multiple agents, humans reached the top of the food chain,
eventually. However, in sociality, education and experience are mandatory; it is not possible to obtainthese immediately.
I would like to add a fourth human trait when we consider our future, namely “optimism”.
The difference between an expected result and the actual outcome has an optimism bias. According to
Sharot [7], approximately 80% of the population people display this bias. In other words, people expectthat good rather than bad things will happen to them.
There is hardly any research that delves into these human traits, examining their relationship withsocial systems. However, it is only natural to consider that they are the basis for the construction ofmarkets and democracy—which form the basic framework of our society.
First, let us consider the markets. Although a market is an “extremely good device for realizing
the short-term desires of people,” it does not “allocate resources in a way that takes account of future
generations.” Future generations cannot participate in today’s markets. Moreover, democracy is a“device that profits people who are currently living,” and it does not “incorporate future generations.”
If political candidates propose policies that would lead to enriching people a hundred years later,
they lose the votes of the current generation [12,13].
Moreover, the maximum number of people with whom a human being is cognitively able tomaintain stable social relationships—the Dunbar’s Number—is approximately 150 [29]. It would not
be erroneous to suggest that markets and democracy are devices that preserve some sort of sociality
when this number is exceeded. Within these devices, a person who displays the optimality principle(i.e., contrast) can also demonstrate both myopia and optimism.
There is no definitive judgment yet on how the Industrial Revolution changed the human traits
and impacted markets and democracy; however, some researchers opine that it allowed the transition
from reliance on organic energy to that on fossil fuel, leading society to focus on growth. According toAllen [10] and Pomeranz [11], the mid-14th century Black Death drastically reduced England’s
population, leading to a high increase in wages. In the early modern era, Europe, and particularly
the UK, experienced a rise in the price of wood due to urbanization; the main energy source became
coal, which was locally abundant and happened to be inexpensive. To fulfill the coal demand of the
day required that the subterranean water accumulating in coal mines be pumped out; instead of theexpensive manual labor, steam engines would work the water pumps. It was exactly this kind of energy
shift that led to the “industrial revolution” and the various innovations that we have experienced.
Innovations continued throughout the Industrial Revolution, and large volumes of inexpensive,
seemingly limitless fossil fuels were used. These factors are likely to have strengthened the humantraits of contrast, myopia, and optimism while weakening the sociality. In turn, the changes in thesetransformed the market, democracy, and innovation. This is likely what has created a society blindly
focused on growth, despite its leading to the various “future failures” mentioned above. On the other
hand, rather than with social institutions as in the Covid-19 crisis, the way we think and behavechanges significantly with radical changes in the environment—which includes the social institutions.

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In other words, our very way of thinking and behaving is shaped by our environment, including oursociety, and in turn, this leads to us changing the social institutions.
If this is the case, the transformation of social institutions themselves should be a major challenge
for the first half of the 21st century. The various fields of social science—which are supposed to be
the engines of institutional reform—have become fixated on individual paradigms; an answer to thequestion of how to transform institutions for a sustainable future has not yet been found. Nevertheless,the current mainstream approach is to coordinate and synthesize knowledge from humanities,
information science, neuroscience, and other fields, in addition to that from the social sciences, and thenuse this to understand human behavior, devise social systems, and solve various problems.
FD takes the opposite position. Traditional social science has assumed that people’s behavior,
way of thinking, and nature do not easily change. However, they are transformed by social institutions
and their feedback. In other words, the market and democracy themselves shape the way we think andbehave. To this end, we design various social mechanisms that transform our way of thinking itself
and test their performance using knowledge from various fields. This is the basic framework of FD.
4. Is Transformation in Favor of a Sustainable Society Possible?
Future Earth (http://www.futureearth.org/) was established in 2012 as an international researchplatform that provides knowledge and action intended to accelerate radical innovation conducive toa sustainable society; it became active by 2015 [30,31]. One of its basic concepts is transdisciplinary
research. Stakeholders and scientists co-design research projects, co-produce knowledge, and co-deliver
results. However, both stakeholders and scientists are part of the current generation, and, despitea winwin outcome in following their own incentives, future generations may still stand to lose.
To improve their odds of winning, the future generation should be included as stakeholders, and thechange target should be the way of thinking and behavior of the current generation.
“FD” emerged in 2012 independently of Future Earth, with the aim of creating human“futurability” [13]. People exhibit futurability when they experience an increase in happiness asa result of deciding and acting toward foregoing current benefits to enrich future generations. FD isthe praxis of creating futurability through designing social systems. It is, fundamentally, a questionof whether the willingness of a parent to eat less, to feed their children more, can extend to a future
generation not related by blood. In epigenetic terms, it is the designing of mechanisms that allow
the expression of futurability that could not be conveyed due to markets and democracy, and thus,
control markets and democracy. This is set up against the background of stubborn concern regarding theconcept of sustainable development (fulfilling the needs of the current generation without disregarding
the needs of the future generation) in Our Common Future, written by the Brundtland Commission in
1987 [32]. For example, in resolving the outstanding debt mentioned above, it is impossible to reducethe burden of the future generation unless sacrifices are made by the current generation.
There are two basic concepts in the FD research framework: “how humans think” and “social
mechanisms” (see Figure 1). In social sciences, in the past, both these concepts were immutableconditions, and the research approach was to investigate what would happen with various issues.
Designating consequential impartiality and efficiency as social aims (while assuming that the humanthought processes or tastes do not change), the mechanism design of the late 20th century took into
account the design of social mechanisms needed to achieve those aims. However, this approach
ignores the viewpoint of changing the way that people think. The nudge method is a behavioral
economics approach where there is no transformation of the social mechanisms and, rather than thechange of the ways of thinking, the alteration of behavior is encouraged. However, this method islikely to be successful in, for example, reducing greenhouse gases by a few percent, but unlikely to
lower them significantly. Although Future Earth and Sustainable Development Goals are calling forthe transformation of the social systems, it seems that markets and democracy are not part of thepicture. FD aims to realize sustainable societies by designing “social mechanisms” that change thevery “way the humans think.”

the concept of sustainable development (fulfilling the needs of the current generation without
disregarding the needs of the future generation) in Our Common Future, written by the Brundtland
Commission in 1987 [32]. For example, in resolving the outstanding debt mentioned above, it is
impossible to reduce the burden of the future generation unless sacrifices are made by the current
generation.

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How humans
think

6 of 21

Fixed
Variable

Social Mechanisms
Fixed
Variable
Traditional
Mechanism Design(Social) Sciences
Behavioral Economics,
Future Earth,
Future Design
IPCC, SDGs

Figure 1. TwoFigure
basic concepts
in theconcepts
FD research.
1. Two basicin the FD research

The FD research ideas come from the Iroquois, a confederation of five tribes of Native Americans
There are two basic concepts in the FD research framework: “how humans think” and “social
born in the second half of the 16th century from the need to oppose invasion. They considered sevenmechanisms” (see Figure 1). In social sciences, in the past, both these concepts were immutable
generations in the future when making important decisions [33]. As one might imagine, they shifted
conditions, and the research approach was to investigate what would happen with various issues.
their perspective to the distant future and looked to the present from there to maintain the peace
Designating consequential impartiality and efficiency as social aims (while assuming that the humanof the confederacy. The American founding fathers George Washington and Benjamin Franklin
thought processes or tastes do not change), the mechanism design of the late 20th century took into
united 13 colonies using federalism ideas learned from the Iroquois. This was underlined during theaccount the design of social mechanisms needed to achieve those aims. However, this approach
Bicentennial of the U.S. Constitution when the Senate and the House of Representatives issued a joint
resolution thanking the Iroquois for their contribution [34]. However, while federalism is ingrained in
the U.S. Constitution, the concept of the “seven generations” appears to have been forgotten.
Of course, “futurablity” is hard to activate even if we assume that humans possess this trait.
Is it possible that new social mechanisms will be constructed, the sociality weakened in the name of
the market, and the democracy strengthened? Will contrast, myopia, and optimism be weakened?
I summarize here the FD research on these issues over the past few years.
5. FD Experiments
Let us outline the experimental research of Kamijo et al. [35], which constituted the starting pointof the FD research. Three-person groups representing different generations were asked to choose
between two options that had different impacts on the next generation; both options involved anamount of money that each group would decide how to distribute among themselves during a 10 min
discussion. The first generation (G1) chose between A ($36) and B ($27). If they chose Option A,
the Options A and B that the next generation could choose from would be reduced by $9. If they chose
Option B, Options A and B for the next generation would remain unchanged. Figure 2a shows thepayoffs up to the third generation. For example, if G1 chooses Option A, then it receives $36, and G2
is left with Option A of $27 and Option B of $18. If G2 chooses Option B, the payoff is $18, and G3chooses between the same Options A and B ($27 and $18, respectively). Contrary to the static prisoner’s
dilemma game, in this scenario, a selfish choice of the current generation burdens the subsequent
generations. Kamijo et al. [35] dubbed this game: the “Intergenerational Sustainability Dilemma Game”(ISDG).
In the experiment, each generation received a table containing the gains of up to the sixth
generation; each generation was made aware that following generations exist. Two hundred andten undergraduate and graduate students of the Kochi University of Technology were selected toparticipate, and paid according to the decisions that had been made; almost all groups chose to
distribute the money equitably.
Starting from the premise that Option A would be chosen automatically if humans activate theircontrast trait (the principle of optimality), one person per group was asked to negotiate with theother two—not for their own sake, but as the representative of the groups from future generations.
This participant was compensated in agreement with the decision made by all three, and designated“imaginary future person”.
Figure 2b shows the results of the ISDG when no imaginary future person participated. For example,
in the first row, all generations chose Option A. Note that the actual experiment continued until the sixthor seventh generation because the final generation would be aware of being the last and consistently
choose Option A. Seven groups out of 25 (28%) chose Option B. Figure 2c shows the ISDG results

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when an imaginary future person was present. In this case, 21 groups out of 35 (60%) chose Option B.
approach:
A humanicebreakerhavinga neutral
attitudetoward Optionsapproach:
A and B
Adeliberative
similar result
was obtainedby Nakagawa
et al.
[36], using
a novelqualitative-deliberative
contributed
substantiallytotheselectionofsustainable
OptionB.
A human icebreaker having a neutral attitude toward Options A and B contributed substantially to theselection of sustainable Option B.

a. Payoff
G1

G2

G3
A 18

A 27
B9
A 36
A 27
B 18
B 18
A 27
A 36
B 18
B 27
A 36
B 27
B 27

b. Results without imaginary future persons
…

G1

G2

G3

G4

G5

A

A

A

A

A

A

A

A

A

B

A

A

A

A

B

A

A

B

B

A

B

B

A

A

B

c. Results with imaginary future persons
G1

G2

G3

G4

G5

B

B

B

B

B

B

B

B

B

A

B

B

A

A

B

B

A

B

B

A

B

A

A

B

A

A

B

B

A

A

A

B

A

B

A

Figure 2. Kamijo et al. [35]—payoff and results.
Figure 2. Kamijo et al. [35]—payoff and results.

The experiment ended with a questionnaire on Social Value Orientation. Participants were
The experiment
ended “individualist,”with a questionnaire
on Socialand
Value
Orientation.
Participants
wereclassified
as “pro-socialist,”“competitor,”“other.”They could
choose fromclassified
as “pro-socialist,”“individualist,”“competitor,”and “other.”
could
three
three
sets ofpayoff levels bothfor themselves
and for a virtual
person.They
Those
whochoosechosefromthe samesetsofpayofflevelsbothforthemselves
and
for
a
virtualperson.
Those
who
chose
the
same
payoffpayoff for both were pro-socialists; those who maximized their payoff were individualists, and thosefor bothwere pro-socialists;
those
who their
maximized
payoffwere individualists,
and those [37].
who
whomaximized
the difference
betweenand thetheirvirtualperson’s
payoff were competitors
maximized
the difference
betweentheir
the “individualist”
virtual person’sand
payoffwere competitors[37]. than
Note
Note
that social
psychology
definestheandterms“competitor”
differently
thatsocialpsychology
definestheterms“individualist”
and“competitor”
differently
thaneconomics. Among the participants, 78% were “pro-socialist.” When no imaginary future person
economics.
participants,
78% were
When no imaginary
future personwaswaspresent,Among
Optionthe
B wasselected only
when“pro-socialist.”
all the group members
were “pro-socialist.”
In thispresent,
OptionB
wasselected
only
when
all
the
group
members
were“pro-socialist.”
In
this
case,
case, “pro-socialists” comprised 76% of the participants who chose Option A. However, when in the“pro-socialists”
comprised
76%person,of the pro-socialists
participants whochose 79%
OptionA. members
However,inwhen
in thepresenceof an imaginary
futurecomprisedof thethe groups
presence
an imaginary
futureperson,pro-socialists
comprised
79% ofthe members
the wasgroupsthatchose ofOptionA and 73%of theparticipantsin the groups
that chose
OptionB. Thus, in
there
no
that
chose
Option
A
and
73%
of
the
participantsinthegroupsthat
chose
Option
B.
Thus,
there
was
significant difference between the proportions of pro-socialists in the two situations. In other words,
no significant
betweenthe proportionsof pro-socialists
the twosituations.Option
In other
whetheror not difference
the individual
participants
were pro-socialist
had noin
impacton selecting
B.
words,
whetherornottheindividual
participants
were
pro-socialist
had
noimpactonselecting
However, when one of the three group members took on the role of the imaginary future person,
OptionB. However,
one duringof the threegroup members
took on theroleof the imaginary futurethat
person’s
behaviorwhen
changedthe discussions
and impacted
thosearound.
person,that
person’s
behaviorchangedduring the discussions
around.
Saito[38]
used thedata fromthis experiment
to conductand
the impacted
followingthosethought
experiment.
Saito
[38]
used
the
data
from
this
experimentto
conductthefollowing
thought
Macro-economically speaking, based on a discount rate r, the G1 gain WA is taken to be experiment.
the present
Macro-economicallyspeaking,
based ona discountrateOptionr, the G1
gainall
WotherA is taken to be the present
valueof the most selfish
payoff stream(i.e.,
G1 selected
A andgenerations selectedvalue ofmoststream(i.e.,
G1 selected
A andchoose
all other
OptionB),theandthe selfish
G1 gainpayoff
WB , thepresent
value
when allOption
generations
thegenerations
sustainable selected
OptionOption
B),
and
the
G1
gain
W
B, the present value when all generations choose the sustainable Option
B. Hence, the following are taken to be true:
B. Hence, the following are taken to be true:

18
27
X∞ ∞ 18
X∞
27
= 36
= ∞
WAW
=A 36
+ +  t = 1 (1 + r )tt ,, WWB B=  t = 0 (1 + r )t t
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If r = 1, then WA = WB = 54. If r > 1, then WA < WB . If the first generation lasts 30 years,(1 + 0.023)30 ≈ 2. Thus, if the discount rate is converted to an annual rate, Option A will be chosen if
the discount rate is 2.3% or higher, and Option B if it is lower.
The results of the experiment above are interpreted as “a change toward a lower generational
discount rate” generated by the introduction of the “social mechanism” of an imaginary future
generation. Although the interpretation is clear, I would note the lingering doubt surrounding thesuitability of a macroeconomic framework that considers the current generation payoff as the present
value of an unlimited payoff stream for all generations.
However, it is impossible to decide the effectiveness of introducing a new mechanism based on
imaginary future generations from only one experiment. Areas with different economic development
and historical and cultural backgrounds must be studied. Hence, Shahrier et al. [39] carried out an ISDG
experiment in Bangladesh, in a megacity with a rapidly growing population (Dhaka) and a rural area
(Bogra). In contrast to the Japanese experiment, where the participants were students, the Bangladeshi
participants were recruited within the community (252 participants per area). Regardless of whether
or not the imaginary future person was present, the selection rate of Option B differed significantly
between Dhaka and Bogra (approximately 30% vs. 80%, respectively; Table 1). The scenario involving
an imaginary future person increased the selection rate of the Option B in Bogra, but not in Dhaka.
The Social Value Orientation questionnaire revealed a sharp gap between the proportion of pro-socialists
in Dhaka and Bogra (21% to 45%, respectively). In contrast to the Japanese, the Bangladeshi participantsreceived a monetary incentive corresponding to the option chosen in the Social Value Orientationquestionnaire, resulting in a rather low proportion of pro-socialists.
Table 1. Results of the intergenerational sustainability dilemma game (ISDG) experiment in Bangladesh.
Selection of Option B

Dhaka

Bogra

With imaginary future person
Without imaginary future person
Proportion of pro-socialists

29%
31%
20%

86%
74%
45%

In light of the results of Shahrier et al. [39], the issue clearly lies with the design of a mechanismthat would allow for a sustainable selection in the ISDG conducted in Dhaka, as well. Kamijo et al. [35]had one person representing the imaginary future generation, increasing the possibility of sustainable
selections. Hence, it would be possible for all the decision-making participants to be part of theimaginary future generation. Will members of the current generation accept decisions made bymembers of an imaginary future generation? To answer this, Shahrier et al. [40] proposed the future
ahead and back mechanism (FAB) mechanism, as follows.
Stage 1: All three participants—as imaginary next future generation members—select either Option A
or B and then submit a request to the current generation (i.e., themselves).
Stage 2: All three participants—as the current generation—select either Option A or B and, if theselection is the same as in Stage 1, the process ends..
Stage 3: For a different selection than in Stage 1, the outcome is decided on a majority rule basis.
Based on the FAB mechanism, the Option B selection rate was 85%, similar to where one person
represented the imaginary future generation in Bogra. However, in this experiment, the pro-socialists
comprised 28% of the participants, while Shahrier et al. [40] found 20%. The increase in sustainabledecision-making was made possible by adding, beforehand, two stages to the majority decision
mechanism—a technique often used in democracy.
However, what if there is only one decision-maker in ISDG, instead of three? Shahen et al. [41]experimented within this scenario by giving participants, if they belonged to the sixth generation,
decision sequences made by previous generations such as ABAAB. Each participant could make

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9 of 2136 different decisions. Consider the case where the participant is not an imaginary future person;
participants are likely to choose the unsustainable Option A when the proportion of previous generations
that chose A is high, or when the number of future generations who can receive positive benefits
is low. This is quite intuitive, in the sense that people of the current generation tend to give up
on making sustainable decisions when previous generations chose unsustainable options, or when
only a few future generations will be left with the same resources, due to being too late or too graveof a current situation for sustainability to be improved. On the other hand, when participants are
asked to take the stand as the future generations, their behavior drastically changes; they become
more sustainable-oriented even when the percentage of unsustainable previous generations is high,or the future generations who can receive positive benefits are few. This suggests that, left to theirown devices, individuals will act selfishly—with no consideration for future generations—when
intergenerational sustainability is highly threatened. Thus, introducing new institutions that could
influence the individual to think from the perspective of future generations might be the only way tomitigate intergenerational unsustainability.
However, what about democratic voting? Katsuki and Hizen [42] conducted a voting experimentwith 156 participants, using the ISDG described by Kamijo et al. [35]. Each generation had threeparticipants, and each participant could cast hypothetical votes as a member of one out of six generations.
If a participant belonged to the second generation, he/she made decisions based on the first generation
choices of either A or B. If a participant belonged to the sixth generation, the number of possible
decisions increased to 64. The methods of voting were: (a) One vote per person, (b) two votes per person,and (c) one vote per two of the participants and two votes per the third. In scenario b, the participants
were instructed to cast one vote for themselves and the other for the future generations. Randomly
choosing three participants from each generation resulted in a choice sequence such as ABAABA,
for example. Fifty million simulations performed for each voting method resulted in Option B being
selected at the rate of 9.25%, 17.11%, and 14.66% for scenarios a, b, and c, respectively. Voting methodsb and c are types of Demeny voting, which will be discussed later. Given that the selecting rate of
Option B in the absence of an imaginary future person was 28% in the Kamijo et al. [35] experiment,
voting may not constitute an effective method for promoting sustainability.
Hauser et al. [43] conducted an experiment using the Intergenerational Goods Game, where five
participants vote for the amount of fish they will catch. The total number of fish is limited, say 100.
If the number of catches is at most 50, the next generation’s resource is 100; otherwise, it is zero.
The study found that median voting works well. For example, assume that the numbers on the ballots
are 4, 5, 9, 14, and 20 (median = 9). Hence, everybody must catch nine fish. If this is the case, the total
number of fish caught is 45; hence the next generation’s fish resource is 100. Consider the case a for
Katsuki and Hizen [42]. Once I establish that the median of AAB is A, and the median of BBA is B,
this matches exactly the majority voting and, apparently, median voting may not work well either.
Deliberation could constitute a method of resolving problems within and between generations.
To show the effect of deliberation alone within the ISDG framework, Timilsina et al. [44] carried out afield study in urban and rural settings of Nepal. When three people were involved, they were asked tochoose an option both before and after deliberating. The results showed that deliberation had hardly
any impact on the selection outcome. That is, this experiment shows that democracy does not always
serve the desired function in solving intergenerational problems. Furthermore, the selection rate of
Option B was 64% in the urban area and 84% in the rural one. That is, the selection rate of B was almost
double in Kathmandu compared to Dhaka—which has a five times denser population. Although due
to Covid-19, migration from urban to rural areas is expected, it is undeniable that the number of people
acting with the future generations in mind will further decline as urbanization continues.
So far, participants in these experiments have assumed the role of imaginary future people
traveling back in time to consider their choices in the present through the viewpoint of the future.
Nakagawa et al. [45] are developing a method named Past Design, in which participants evaluate past
events from the viewpoint of the present. In one experiment, using the case method, 155 participants

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10 of 21from the Kochi Prefecture—where 84% of the land area is forested—were presented with the history,
current situation, and issues for debate surrounding Kochi’s forests, and also with five relevant policy
options/scenarios (maintenance of status quo; intentional neglect of inefficient forests; minimum carefor inefficient forests; providing forest roads for the continuation of forestry business; turning forested
land into recreation forests). When no conditions were imposed and before debating, the option mostfavored by the groups representing only the current generation was turning the forested land into arecreational forest. After debating the future of the Kochi’s forests from the viewpoint of the present,
the most favored scenario changed to providing minimum care for inefficient forests. Simultaneously,
the rest of the groups were asked to follow the same twin procedures. The scenario selected by mostindividuals—after advising people from 30 years ago—was to provide forest roads that would allow
continuing the forestry business; the same scenario was most frequently selected after the subsequent
debate as an imaginary future generation. In other words, even without debate, the “social mechanism”
of looking back at the past—or Past Design—had a significant effect on sustainable selection.
Returning to a topic mentioned previously, public debt sustainability is an important issue in Japanand many other countries. Hiromitsu [46] and Nakagawa et al. [47] carried out subject experiments
using an imaginary future generation. Hiromitsu conducted experiments in different parts of Japan,
considering two scenarios: Whereby the burden is postponed for 30 years or more (Option A) or shared
between the current and future generations (Option B). Ordinary people (ranging in age from theirlate teens to their seventies) were grouped in teams of three and asked to choose between A and B
through debate. Similar to Kamijo et al. [35], some teams were assembled from members of the current
generation, and some contained representatives of imaginary future generations (one teammate played
an imaginary person of the future). Sixty of the 83 current generation teams (72.3%) and 57 of the
65 imaginary future generation teams (87.7%) chose Option B. In addition, the “silver democracy
hypothesis” (older people tend to postpone a burden) was also investigated. However, Option B
was selected less often as the age of the participants increased, this change was small compared tothe profit-and-loss arithmetic implied by their own life expectancy. Further, the pros and cons of
the “deliberative democracy hypothesis” (when debating is involved, Option B is more likely to bechosen) were investigated; this hypothesis seemed to be supported by the increase of the selection
rate of Option B from 71.6% before discussion, to 87.7% after discussion. Hiromitsu surmises that this,perhaps, could be attributed pressure to conform exerted by the group.
Nakagawa et al. [47] recruited 379 ordinary people from the Kochi Prefecture, Japan, and conducted
a deliberation experiment for teams of four; all members of a team belonged either to the current
generation or the imaginary future generation. Employing the Harvard case method used in businessschools, materials were developed to teach participants notions of national and prefectural financial
administration in a short time. Among these, two policies were proposed as national policies
maintaining the status quo or reducing the budget of local prefectures and two as prefectural policies
maintaining the status quo or the support for specific regional agglomeration aimed at regional
self-reliance. The participants assigned to the current generation group debated the most favorable
policies for the society of year 2047 out of the proposed four, chose one, and then reported theirpreference individually. The imaginary future generation group was asked to follow two procedures.
First, before debating, they were asked to complete a Past Design session: They had to read 30 years
old newspapers and then send advice to the people of that time. Subsequently, they “time-shifted”
30 years into the future, debating from the perspective of the year 2047 which of the four policies theywould want people of the year 2018 to choose. They reported their selection from the perspectiveof an individual living in 2017. The experiment ended with questionnaires designed to measure the“generativity” (engaging actively in behavior that creates value for the next generation) and “criticalthinking” (the quality of being able to think logically without bias and creativity), developed by
McAdams and de St Aubin [48] and Hirayama and Kusumi [49], respectively. A higher than the medianscore in at least one of these two indicators suggested that an imaginary future person was more
likely to support specific regional agglomeration aimed at regional self-sustainability than a current

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generation person. In other words, people with a high score in at least one of these indicators chose ascenario that took into account the future generations, owing to experiencing the “social mechanism”
of becoming a future generation person in the twin procedures. Although not an experiment, it should
be noted that Saito [50] created a fictitious deliberation narrative with an imaginary future generationon the issue of the consumption tax. An imaginary future person who supported gradual tax increase
starting from 2020 was supported by other participants.
The experimental results listed above suggest that one can assume the role of an imaginary
future person, think from the standpoint of future generations, and consider the wellbeing of future
people, even after one “returns” to the present. In this case, the question to be answered becomes:
What type of people possess these characteristics? Within the same framework as the fiscal experimentin Nakagawa et al. [47], Nakagawa et al. [51] have tried to answer this using critical thinking andgenerativity for testing purposes. Critical thinking measures “whether you tend to always thinklogically,” and “whether you tend to be curious about everything all the time” (see also [52]). They foundthat a person with higher levels of both traits is more likely to successfully become an imaginary future
person; a person with high levels of curiosity can think about the wellbeing of future generations evenafter “returning” to the present; a person who is always more likely to be aware of future generations(i.e., a person with a high generativity trait) is also more likely to act with the wellbeing of future
generations in mind, after returning to the present. If we were to create an organization such as someministry of the future, we would be looking to fill it with people possessing these characteristics.
Another burning question is: As the falling of birth rates and the aging of society continues,
what type of electoral system would be suitable to promote a sustainable society? Kamijo et al. [53],as a mechanism to reflect the children’s voice, conducted an experiment based on the voting systemsuggested by Demeny [54]. This system gives to children voting rights exercised by their parents
by proxy. Three types of votes were used by parents: One vote, two votes (one for parent and one
for a child), and no vote (since this person belongs to a future generation). Participants voted for
either Option A (the current generation receives a large reward) or B (the reward is split evenly
between the current and future generations). When the Demeny voting system was used and bothparticipants had one vote, half of the ones previously voting for B cast their vote for A. In other words,
while under normal voting conditions, many participants took into account the future generations andchose B (equivalent to the older generation at the life stage of having no children or adult children),under Demeny voting half of the one vote participants changed their support in favor of the Option
A—which benefited themselves. This suggests that the Demeny voting system does not serve thepurpose for which it was intended.
Kamijo et al. [55] invited parents with children below and above the legal voting age (1000 each) toparticipate in a survey experiment where participants donated to a non-profit organization benefiting
a future society. The donation amount was determined by the participants through voting. Two voting
systems were observed: Regular and Demeny (parents gave one vote on behalf of their child if they
had any). In general, mothers of children below voting age displayed more altruism for posterity inthe voting process. However, when the Demeny voting system was used, this difference vanished,
and the average donation amount decreased. In other words, Demeny voting does not necessarily leadto decision-making that benefits future generations. Kamijo et al. [53] compared the case where the
Demeny voting specified that one extra vote was cast for future generations with the case where it did
not. Again, they observed no effect due to Demeny voting when that stipulation was not explicitly
stated [42]. To mitigate this issue, Hizen [56] suggested the necessity of introducing other systems thanvoting. Examples of such systems include the “Mission: The Future,” established in Sweden as an
executive government branch to investigate long-term problems, and the ombudsman system set in
Hungary to oversee the executive government branches from the viewpoint of the future.
Hiromitsu [57] showed results that are different from the “silver democracy hypothesis” andconcluded that the judgment of individuals becomes unbiased as they age and approach Nirvana.
Saito and Kameda [58] verified the strength with which older people desire to represent the welfare of

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future generations by conducting a postal survey of 2000 randomly sampled residents of the Bunkyo
ward of Tokyo, aged 18 or older (772 valid responses). The survey revealed that the level of a person’s
desire to represent future generations could be anticipated based only on their stage in life (respondents
were grouped by the following stages: No children, children but no grandchildren, and grandchildren).
They assessed the desire to represent future generations using the question: “For the sake of thegenerations as yet unborn, would you like to take on the role of advising on existing social policies
from the position of future generations?” The most important point of this question is that it does not
ask to advise (future) generations already born (i.e., grandchildren), but “generations as yet unborn.”
In other words, as people progress through life stages, they shift their focus toward the welfare of
future generations that will comprise the society after their death. This fact suggests the possibility thatthe sustainability of future generations is understood in relation to “third parties with no connection
to oneself”—the generations who will come after one’s own grandchildren. Saito and Kameda [58]emphasized the possibility that, when people face the sustainability problem, they are buoyed by“expanded egoism,” seeing it not as related to unselfish, altruistic behavior, but as their own problem.
Another possible explanation is that, although obscured by the market and democracy, the “expanded
egoism” or “futurability,” fostered as human beings have progressed through life stages, is a social
system similar to an imaginary future generation.
6. What Is the Premise of the Imaginary Future Generation?
Kobayashi [59,60] developed an argument rationalizing the introduction of an actor (imaginary
future person) representing the good of future generations as follows. The human being defined by
the Rawls’ [61] theory of justice is a self-interested rational individual. Behind a “veil of ignorance”(“original position,” where a person knows neither the generation to which they belong nor their own
age, wealth, or health), a person should apply the difference principle (the maximin rule, a social
system in which the utility of the least-fortunate generation is maximized within its various systems).
However, even if a social contract can be agreed upon in the original position when the veil of ignorance
is lifted, and history begins, a self-interested rational generation has no incentive to follow such a social
contract. In other words, the current generation has no incentive to sacrifice its own gain to secure
gains for future generations. This is because we face the time inconsistency problem, whereby future
generations can impose no penalty if the social contract is broken (Calvo [62]).
Here is an experiment on the veil of ignorance by Klaser et al. [63]. Each generation consistsof three participants supposed to divide 21 Euros. If the total is at least 16 Euros, the game ends.
If not, the game continues. That is, equitable and efficient division to continue the game is that eachparticipant claims 5 Euros. Each participant knows which generation he/she belongs to but does
not know the total number of generations involved. Under these conditions, six cases ended in one
generation, and the two cases ended in two generations. On the other hand, without knowing which
generation they belong to, the three would vote until they are unanimous on what allocation should
be made under the veil of ignorance. After that, they would know which generation they belong to.
Four ended in one generation, and two ended in two generations. The veil of ignorance faces a time
consistency problem in this experiment, finding also supported by Wolf and Dron [64].
If an imaginary future generation is introduced into society ahead of its time, it is possible
for the happiness of the least-fortunate generation of that society to improve. People in theoriginal position—who stand behind the veil of ignorance, in anticipation of happiness—agree
to the introduction of an imaginary future generation as a social contract [60]. To establish such a
new social contract, the imaginary future generation must possess strong altruism toward future
generations. Kobayashi [60] weakened the assumption of self-interested rational individuals andclaimed that people display a “weak altruism” with regard to future generations. When people froma future generation fulfill their assigned roles, they can gain the empathy of others (Smith, [65]);
the empathy received produces positive feelings, strengthening the altruism of these imaginary future
persons, and helping establish a new social contract theory.

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In constructing his principle, Rawls [61] excluded the environment that could foster feelingsof altruism and empathy, imagining instead self-interested, rational actors. However, as shownby the behavioral ecology research of Saito and Kameda [58], humans display “expanded egoism.”
If we can activate futurability by introducing the social mechanism of the adoption of an imaginary
future generation, this type of social contract can be aligned with the new social contract theory of
Kobayshi [59,60].
However, if the starting point of our discussion is not the assumption of a self-interested rational
actor, Hiromitsu [57,66] considers that agreement between people of the same generation supports theintergenerational principle; this agreement is, in turn, supported by “the reasonable” described by
Rawls [67]. “The reasonable” is a concept that Rawls contrasts with “the rational”, and describes people
who understand that, if other people respect the fair conditions of cooperation, the principle in question
has to be respected even at the expense of self-gain. In addition, Hiromitsu [66], while focusing on thefact that Rawls himself intended “the reasonable” to be only a political concept, claims that this imageof the human beings is analogous to that proposed by Hume [68], who argues for altruism as their true
character. If we view the expansion of reasonableness as including the fate of future generations as“futurability” within FD, this provides a logical foundation of the framework for designing or agreeing
to social systems that activate this futurability.
7. Practical Application of FD
FD practical applications are underway in parallel to the experimental research mentioned above.
The main framework for laboratory and field experiments relay on researchers presenting scenarios
likely to happen in the future. This enables us to understand if the selected scenarios change when
the future is examined from the viewpoint of the present, and vice versa, as by an imaginary future
generation. However, in FD practical applications, the participating citizens themselves design the
scenarios, and the issue becomes their choice of scenarios and present-day policies. The proposed
scenarios differ qualitatively when considering the future from the standpoint of the present, and when
examining the present from the viewpoint of the future. The following paragraphs describe practicalcases applied in Yahaba, Iwate Prefecture, and Matsumoto, Nagano Prefecture.
In Yahaba, an imaginary future generation was created in the present to represent future
generations’ interests and approach vision design and decision-making from their perspective [69].
It examined the possibility of decisions made through negotiations between this future generation’s
representatives and the current generation, considering the conflict of interests of the different
generations. Because the Cabinet Office required all municipalities to produce a “long-term vision” forthe year 2060, monthly workshops were held between November 2015 and March 2016. Four teams offive to six residents of Yahaba were assembled; two of them were asked to think about the Yahaba of theyear 2060 as members of the current generation, and propose policies at the present time, for the future;
the remaining teams were asked to “travel to 2060 in a time machine” and draw up policies from there.
At this point, I would like to outline the nature of the debate based upon Hara et al. [69]. Let us
start from the position of the imaginary future generation. First, their overriding aim was securing andbuilding a prosperous life for the future inhabitants of Yahaba; debates arose around their livelihood,
lifestyle, and values. For example, while the current generation proposed policies such as free children
medical care to increase the population directly, the imaginary future generation did not have sucha specific aim, discussing instead the possibility of population increase as a result of vision andpolicies. Second, they did not propose individual strategies and long-term ideas to achieve their aims;
they rather constructed a narrative connecting strategies and ideas. Third, if that helped achieve theaim, then existing systems, etc., were regarded as flexible and open to change. Fourth, they displayed
a willingness to actively incorporate any radical technical innovations that may occur in the future.
Fifth, they demonstrated the highest possible sensibility and awareness by considering new strategies
to respond to urbanization and the aging of society. Sixth, having become aware of the current issues,
they devised a new vision to eliminate those.

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Now, let us examine the approach of the current generation. First, a better life at present became theprimary focus. For example, they proposed things such as “eliminating waiting lists for nursery schools”
or “improving care for the elderly.” Second, they displayed the tendency to consider improvements toexisting facilities and frameworks. Third, they leaned toward proposing policies that did not burden
them. Fourth, they favored policies producing results in the short term. Fifth, they tended to consider
polices by comparing the corresponding policies of other regions. Sixth, they also tended to regard
existing frameworks and systems as immutable.
The current generation regarded the future as an extension of the present time, constructed visions
that resolved immediate problems, and proposed ideas based on current conditions and restrictions.
Meanwhile, the imaginary future generation creatively gave the highest priority to solving the mostcomplicated and time-consuming problems and depicting the future thoroughly regardless of current
circumstances. They noted the physical and aesthetic merits and resources of the region and examinedways to utilize these on a continuous basis.
Six months after the field application described above ended, Nakagawa et al. [70] conductedinterviews with several of the participants and reported that the locals who had undertaken the role ofimaginary future persons experienced no conflict between the current generation and imaginary future
person parts of themselves, having a comprehensive overview of both sides. In addition, the very actof thinking as an imaginary future person was a joy; in their everyday life, they found themselves
thinking like an imaginary future person automatically. The impact of this experience persisting six
months later shows that the effect of introducing imaginary future persons is robust. This validates thepossibility to activate the futurability in humans by prompting them to think like imaginary future
people. However, when the current generation examines the future, future generations are seen
as outsiders.
Next, 26 of the 1000 randomly sampled residents of Yahaba were recruited to participate indiscussions in the period January–March 2017. The theme of this practical FD application by
Hara et al. [71] was to develop a plan for public facilities and municipal housing in the year 2060.
Given the effectiveness of the FAB mechanism as described previously, deliberations were carriedout based on the following arrangement: The first session of deliberations was conducted from theperspective of the current generation; in the second session, one month later, proposals for policies
and long-term ideas were discussed from the standpoint of an imaginary future generation living in
the year 2060; in the third session, vision proposals and decision-making were welcomed from theperspective of either the current or the future generation. Participants filled out various questionnaires
after each session. As shown by Nakagawa et al. [70], it was ascertained that the viewpoints of fromboth the current generation and imaginary future could coexist within one individual. In addition,
when examining the “degree of shared viewpoint”—a yardstick measuring the extent to which persons
in the current and future generation shared views—it was found that the higher that degree, the stronger
a person’s awareness of the current generation’s responsibility. Moreover, in the policy proposals wasobserved a focus on both “the possibility of realization” and “leaving scope for future generations to be
in a position to decide for themselves”. In addition, the language analysis of the first set of discussions
revealed that there were many opinions and proposals relating to facilities as physical items. However,elements missing in the first session emerged as the second and third sessions progressed, such asconcern about the current residents of municipal housing.
Yoshioka [72] had been conducting waterworks workshops for the residents at Yahaba since 2008
(no FD methods were involved) and observed that the participants’ way of thinking could be changed
from taking an inexpensive and reliable water supply for granted to believing that it is unreasonable
to expect such facilities without any cost to oneself. FD sessions started in 2015, and Yahaba held
resident FD workshops on the increasingly difficult-to-maintain water utilities in 2017. Consequently,
residents proposed a water rate increase on their own; the town collected an extra 6% the next year,with little opposition. After observing these workshops, Mayor Shozo Takahashi declared Yahaba an
FD Town in his 2018 policy speech and, in April 2019, established the Future Strategy Office. The firstSustainability 2020, 12, 6467

15 of 21task of the office was to develop a future plan in cooperation with the residents, using the FD approach(the plan development is scheduled to be completed presently). Thus, Yahaba Town is set to change
the town structure, while the very mindset of its residents is also beginning to shift.
A three-day workshop for local government workers was held in November 2017 in Matsumoto,
the Nagano Prefecture (Nishimura et al. [73]), to discuss how to work out a basic concept for the
new city hall due to be rebuilt. That was followed by a two-day workshop for the general public(January/February 2018). The current generation group attached information to a blank map andconducted the “spatial journey task” of writing down the problems encountered for each region.
The imaginary future generation group, in addition to the blank map task, conducted the “spatial
and temporal journey task.” Based on a timeline of Matsumoto City from 1960 to 2060, they lookedback at past events and imagined the shape of the region and the society of the future. They also
added predictions for various future statistics and technological innovations on the timeline. On thefirst day of the local government employee workshop, all groups undertook the spatial journey task.
On the second day, only the future generation group completed the temporal journey task; this groupexperienced a lively exchange of views at the meta-level regarding the future and the functions left for
the local government after chronic low birthrate and increased artificial intelligence use. The starting
point in the current generation group related to current problems, and methods to resolve these were
examined. The general public workshops yielded the same results.
Nishimura et al. [73] administered questionnaires on discount rates before and after the events.
No change was found for the current generation group. For the future generation group, the discountrate was lower after experiencing the temporal journey task and, thus, acquiring a long-term viewpoint.
Furthermore, women’s discount rate was lower than that of men. This experiment was designed tocompare the “spatial task” and the “spatial and temporal journey task” + “imaginary future generation.”
It may have been possible to verify the effect of the imaginary future generation if “spatial and temporaljourney task” groups with no imaginary future generation element were considered.
Future designers of a city may ask participants at various practice sites to time travel to theyear 2050, for example. However, it is hard to believe that an ordinary citizen can be an imaginary
future person without effort. To look at this aspect, Nakagawa interviewed people who became
imaginary future people from among the participants in the first practice in Yahaba; two 10-min
narrated picture-story shows were created based on the interviews (Nakagawa et al. [74]). Rather thandirectly using them in practice, their effectiveness was tested first on regular people. The attitudes of
186 participants immersed in the same environment of financial sustainability problems of [45] were
evaluated before and after they were shown one picture-story show. It was found that exposure to
this visual narrative significantly altered participants’ preferences as proxies for future generations.
Specifically, after this intervention, participants were able to avoid regret for not doing certain things in
the past [75]. They tended to wish that the current generation had chosen a more distant option fromthe status quo. Based on the results of this study, four picture-story shows were created and presented
in many practice sites.
In many practical FD applications, the designers form groups of approximately four participants.
The group members discuss the issue in depth, from the viewpoint of the future generations. Usually,a facilitator controls the deliberations; both participants and facilitators summarize the results at
the end. It is of crucial importance to note that the act of summarizing deliberations can never be
arbitration-free. In fact, there are infinite ways of selecting and connecting statements mentioned
during deliberations meaningfully; the way these are done depends on the person doing it. With thisunderstanding, Nakagawa [76] proposed a method to visualize contexts of deliberations using a
dialog map, and extract viewpoints of the participants based on the transcripts. This method is applied
to secure the transparency of the act of summarizing the deliberation even if, in principle, objectivenesscannot be achieved. During the most creative deliberations, the participants’ statements intertwine as
if they were running up a flight of stairs. Thus, a collective new vision is created, which could nothave been created by individual members alone. By visualizing such lines of deliberation (or context),

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this method provides clear reasons for why some parts of the deliberation are prioritized rather than
the rest, to extract visions ex-post (see also [77]).
Let me show several other practices in Japan. Japan has faced various Natural Hazard Triggering
Technological Disaster (Natech) events. Kurashiki [78] assumed that the population change in a cityin the Osaka and Nankai areas was a consequence of the megathrust earthquake, asked participants
to propose various policies from the perspective of risk communication, and verified the effect ofan imaginary future generation. Other FD projects in progress are related to renewable energy andenvironment (Suita City, Osaka metropolitan area [79]), infrastructure (Uji City, Kyoto metropolitan
area; Saijo City, Ehime prefecture), global warming (Kyoto City), water and sewer (Kyoto prefecture),water (Nagaokakyo City, Kyoto metropolitan area), future planning with Kochi Association of Corporate
Executives (Kochi Prefecture), urban redevelopment (Ohnuma Town, Hokkaido [80]), and more.
In addition, Matsunaga and Managi [81] question the nature of social sustainability and propose
replacing the GDP with a new, inclusive wealth measure (wealth available to the society to enhancewellbeing, benefiting both those alive today and future generations). This has the potential to become
an indispensable indicator for evaluating FD research.
So far, in practicing FD, researchers and local government officials collaborated to provide anappropriate “mechanism” for each municipality and held workshops for the local residents. Note thatthe researchers merely provide mechanisms for residents to make decisions on, and do not address
problems themselves. When, where, and how to bring in problem-solving experts is an important partof the design of “mechanism,” of course. However, an FD researcher should not interfere with the
problem itself the same way a football referee should not play in a game, and a spectator should notenter the field and play. Furthermore, it follows Hayek’s position that “the knowledge of the particular
circumstances of time and place” in an area is not easily transferred to outsiders [82,83]. Although eachresearcher seems to adopt in practice a variety of implicit rules, I would like to present here principles
adopted by the Research Institute for FD of the Kochi University of Technology (RIFD) [84].
Principle 1: Designers should not be players
In the practical designing of a workshop, any researcher should assume the role of a supporter;
the person in charge should make the decisions. The practice should be conducted by the people incharge, and the researcher should not have any role in the practice. Furthermore, the researcher must
not force or guide the participants or those in charge of any aspect of the FD practice.
Principle 2: Critical Publicity
Kant [85] defines this concept by stating that “all actions having relations to the rights of othermen, whose maxims do not allow publicity, are unjust.” Whether it is FD or not, any practices
involving citizens must satisfy Kant’s criterion. Based on this principle, RIFD proposes the following
two principles.
Principle 2-a: Informational publicity
All parties involved must share information in both directions with all other parties. For example,
regarding emails, this means that all parties are always on the mailing list. Any other way of exchanging
information does not satisfy this principle. The concentration of information refers to a form of networkin which one person acts as a hub, and information is transmitted to others only through that person.
Principle 2-b: Equality
This requires researchers and citizens to participate on an equal footing. In practice, as Hayek [82] andScott [83] show, the researchers who design the mechanism lack field knowledge, where RIFD shifts
the weight to the citizens. In other words, this principle implies refusing to be led by the researcher.
Leading here means one person chairs or presides over a deliberation, leads the decision-making
process, and so on. For example, consider the case in which one person assumes the role of the hub andleads the exchange of emails and meetings for researchers only, omitting the person in charge. Such amethod of recognizing the person who becomes the hub does not satisfy the condition of equality.

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Principle 3: Evidence-based selection of method
A new method must be validated beforehand through theoretical verification or laboratory testing,rather than directly used in practice. When using an untested method, the people involved should beaware of that fact, and the advantages and disadvantages of the method must be made clear; only theymust choose if to use it or not.
Principle 4: The “fading away” principle
When researchers and outsiders support citizens, including a variety of stakeholders, the latter canconduct practical applications without further support from the former. In other words, supporters are
assumed to withdraw in the future completely.
Principle 5: The “external eye” principle:
If a researcher serves as a supporter for an FD session, he/she must submit to critical evaluation by
a party external to the design of the mechanism, the practice, and the output of the practice. In thiscontext, the external parties exclude the supporter in question and outside stakeholders.
8. Outstanding Issues with FD—in Lieu of Conclusions
FD research program began in earnest in late 2015, and now encompasses a variety of issues.
With reference to Kobayashi [26], let us examine three of the issues.
The first relates to whether the imaginary future generation will function as intended. In theexperiments reviewed here, people have been found to self-activate their futurability. In addition,
in FD practical applications, they exercise an “originality” not found when the future is viewed fromthe position of the current generation. That said, the mechanism of the “mind” at work is still unclear.
As a result, Aoki et al. [86] conceived a research area dubbed “neuro FD,” in which collaborations
between psychology, biology, neuroscience, and related fields are essential.
Even if many people are willing to become imaginary future persons, how will they function within
existing organizations? This problem also relates to the second issue: Will it be possible to compensate
for the impulsiveness and optimism of the democracy by merely constructing, within existing
frameworks, new organizations such as a Ministry of the Future, future departments within various
bodies, and a future discussion chamber? We certainly do not know yet how policies will be drawn up
or chosen from among various proposals, and how they will be pursued. In other words, with the issueof designing “social mechanisms” offering places where the general public can demonstrate futurability
and originality, we also face the issue of designing new “social mechanisms” able to implement
such ideas. We must learn to construct social mechanisms in which general public members—who
understand the perspective of the future generations—can draw up and implement various policies.
Moreover, they should do that not as a task for the sake of others, but as one that relates directly tothem. This frame has the potential to change the existing representative democracy significantly.
The second FD research issue is the validity of the creation of an imaginary future generation(with new systems such as a Ministry of the Future) within a democracy. For example, with Demenyvoting, parents with proxy votes for their children ultimately obtain the right to vote more than once,
which contradicts the democratic principle of “one person, one vote” and lacks validity. With therationalization of the imaginary future generation examined in Section 5, the necessity to consider thevalidity of a Ministry of the Future and of various social mechanisms that may be proposed will arise
at some point.
The third FD issue refers to what needs to be done so that ordinary people automatically become
imaginary future persons. According to Kobayashi [26], “the next generation to whom we are bound tocontribute must be regarded as something that has permanence,” and we must understand that there
is value in contributing to the progress of human intelligence, i.e., to progress in “expanded reason.”If “expanded reason” rings alarm bells regarding the sustainability of the natural environment andsocieties of the next generation, we should begin taking countermeasures now. Kobayashi argues that,if “progress in expanded reason” can be considered an asset, implementing countermeasures todaySustainability 2020, 12, 6467

18 of 21is only logical if the value of that asset is expected to be undermined in the future. Self-sacrificing
behavior on behalf of the next generation is transformed, for the current generation, into logicalbehavior, to maintain the value of its own asset. Such an attempt can be found in [87].
In addition to the issues described above, another important aspect that requires attention isreforming the impulsive market from the viewpoint of FD. One strategy considers using the market bysetting limits (within the carbon budget) on the amount of fossil fuel that can be burned each year andtrading the relevant emission rights (volume). It is still unknown how this relates to futurability.
Finally, let us consider the possibility of radical innovations in science from the viewpoint of FD.
Although, from the perspective of evolutionary biology, futurability is not a human quality that ought
to survive, it clearly does find a way to stay relevant. It is important to reexamine existing frameworks
to investigate why this should be so. Moreover, discounting future economic gains at the expense of
future generations for the sake of the current one is the norm. Every aspect of life and decision-making
lacks the perspective of future generations. Thus, to ensure sustainable environment for generations tocome, perhaps the revolutionizing of science itself is required.
Funding: This research was funded by the Japan Society for the Promotion of Science (Scientific Research A
24243028 and 17H00980) and the Research Institute for Humanity and Nature (RIHN Project Number 14200122).
Acknowledgments: This paper is an expansion of an invited lecture presented at the symposium “Future design
and a new theory of the wealth of nations: how can we design sustainable societies for the future?”, which took
place at the 2017 annual conference of the Society for Environmental Economics and Policy Studies. I would liketo express my gratitude to Ryuta Aoki, Keishiro Hara, Toshiaki Hiromitsu, Yoichi Hizen, Tatsuya Kameda, Yoshio
Kamijo, Keiichiro Kobayashi, Yutaka Kobayashi, Koji Kotani, Nobuhiro Mifune, Yoshinori Nakagawa, Naoko
Nishimura, Arpana Pandit, Makoto Saito, Yoshimatsu Saito, Mostafa Shahen, Shibly Shahrier, Kaoru Sugihara,
Raja Timilsina, Makoto Usami, Ritsuji Yoshioka, and Jingchao Zhang for their helpful comments on this paper.
Conflicts of Interest: The authors declare no conflict of interest.

References
1.
2.
3.

4.

5.
6.
7.
8.
9.
10.
11.
12.
13.
14.

Steffen, W.; Broadgate, W.; Deutsch, L.; Gaffney, O.; Ludwig, C. The trajectory of the Anthropocene: The great
acceleration. Anthr. Rev. 2015, 2, 81–98. [CrossRef]
Rockström, J.; Steffen, W.; Noone, K.; Persson, Å.; Chapin, F.S.; Lambin, E.F.; Lenton, T.M.; Scheffer, M.;
Folke, C.; Schellnhuber, H.J.; et al. A safe operating space for humanity. Nature 2009, 461, 472–475.
Steffen, W.; Richardson, K.; Rockström, J.; Cornell, S.E.; Fetzer, I.; Bennett, E.M.; Biggs, R.; Carpenter, S.R.;
De Vries, W.; De Wit, C.A.; et al. Planetary boundaries: Guiding human development on a changing planet.
Science 2015, 347, 1259855. [CrossRef] [PubMed]
Steffen, W.; Rockström, J.; Richardson, K.; Lenton, T.M.; Folke, C.; Liverman, D.; Summerhayes, C.P.;
Barnosky, A.D.; Cornell, S.E.; Crucifix, M.; et al. Trajectories of the Earth System in the Anthropocene.
Proc. Natl. Acad. Sci. USA 2018, 115, 8252–8259. [CrossRef] [PubMed]
IMF DataMapper. Available online: https://www.imf.org/external/datamapper/G_XWDG_G01_GDP_PT@
FM/ADVEC/FM_EMG/FM_LIDC (accessed on 10 June 2020).
Sapolsky, R.M. Super humanity. Sci. Am. 2012, 307, 40–43. [CrossRef] [PubMed]
Sharot, T. The optimism bias. Curr. Biol. 2011, 21, R941–R945. [CrossRef]
Hobbes, T. Leviathan; Oxford University Pess: Glasgow, UK, 1651.
Locke, J. An Essay Concerning Human Understanding; Hackett Publishing: Indianapolis, IA, USA, 1690.
Rousseau, J.J. Du Contrat Social; Ou, Principes du Droit Politique; Marc-Michel Rey: Amsterdam,
The Netherlands, 1762.
Saijo, T. Future Design. In Future of Economic Design: The Continuing Development of a Field as Envisioned by Its
Researchers; Laslier, M., Sanver, Z., Eds.; Springer: Berlin/Heidelberg, Germany, 2019.
Saijo, T. Future design. In Future Design: Incorporating Preferences of Future Generations for Sustainability;
Saijo, T., Ed.; Springer: Berlin/Heidelberg, Germany, 2020.
Allen, R.C. The British Industrial Revolution in Global Perspective; Cambridge University Press: Cambridge,
UK, 2009.
Pomeranz, K. The Great Divergence: China, Europe, and the Making of the Modern World Economy;
Princeton University Press: Princeton, NJ, USA, 2009.

Sustainability 2020, 12, 6467

15.
16.
17.
18.

19.
20.
21.

22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.

37.

38.
39.
40.
41.
42.

19 of 21

Rolling Updates on Coronavirus Disease (COVID-19). Available online: https://www.who.int/emergencies/diseases/novel-coronavirus-2019/events-as-they-happen (accessed on 10 June 2020).
Coronavirus. Available online: https://www.worldometers.info/coronavirus/ (accessed on 1 June 2020).
Schäfer, A.W.; Waitz, I.A. Air transportation and the environment. Transp. Policy 2014, 34, 1–4. [CrossRef]
Iacus, S.M.; Natale, F.; Santamaria, C.; Spyratos, S.; Vespe, M. Estimating and projecting air passenger traffic
during the COVID-19 coronavirus outbreak and its socio-economic impact. Saf. Sci. 2020, 129, 104791.
[CrossRef]
GDP Growth (Annual %). Available online: https://data.worldbank.org/indicator/NY.GDP.MKTP.KD.ZG(accessed on 10 June 2020).
Market Forecast for Commercial Aircraft. Available online: http://www.jadc.jp/files/topics/143_ext_01_0.pdf(accessed on 10 June 2020). (In Japanese).
Graver, B.; Zhang, K.; Rutherford, D. CO2 emissions from commercial aviation. The International Councilof Clean Transportation. Working Paper 2019-16. Available online: https://theicct.org/sites/default/files/
publications/ICCT_CO2-commercl-aviation-2018_20190918.pdf (accessed on 10 June 2020). (In Japanese).
Crutzen, P.J.; Stoermer, E.F. The Anthropocene. Glob. Chang. Newsl. 2000, 41, 17–18.
Crutzen, P.J. Geology of mankind. Nature 2002, 415, 23. [CrossRef]
Global Footprint Network. Available online: https://www.footprintnetwork.org/our-work/sustainabledevelopment/ (accessed on 10 June 2020).
Hansen, G.D.; İmrohoroğlu, S. Fiscal reform and government debt in Japan: A neoclassical perspective.
Rev. Econ. Dyn. 2016, 21, 201–224. [CrossRef]
Kobayashi, K. Three concerns in future design. Trends Sci. 2018, 23, 28–30. (In Japanese) [CrossRef]
Deneen, P.J. Why Liberalism Failed; Yale University Press: New Haven, CT, USA, 2018.
Bacon, F. Of the Proficience and Advancement of Learning, Divine and Human; HardPress: Miami, FL, USA, 1605.
Dunbar, R.I. Neocortex size as a constraint on group size in primates. J. Hum. Evol. 1992, 22, 469–493.
[CrossRef]
Van Der Hel, S. New science for global sustainability? The institutionalisation of knowledge co-production
in Future Earth. Environ. Sci. Policy 2016, 61, 165–175. [CrossRef]
Salmon, R.A.; Priestley, R.K.; Goven, J. The reflexive scientist: An approach to transforming public
engagement. J. Environ. Stud. Sci. 2017, 7, 53–68. [CrossRef]
World Commission on Environment and Development. Our Common Future; Oxford University Press:
Oxford, UK, 1987.
Constitution of the Iroquois Nations: The Great Binding Law, Gayanashagowa. Available online: https://www.constitution.org/cons/iroquois.htm (accessed on 10 June 2020).
100th Congress 2D Session H. CON. RES. 331. Available online: https://www.senate.gov/reference/resources/
pdf/hconres331.pdf (accessed on 10 June 2020).
Kamijo, Y.; Komiya, A.; Mifune, N.; Saijo, T. Negotiating with the future: Incorporating imaginary future
generations into negotiations. Sustain. Sci. 2017, 12, 409–420. [CrossRef]
Nakagawa, Y.; Kotani, K.; Kamijo, Y.; Saijo, T. Solving Intergenerational Sustainability Dilemma Through Imaginary
Future Generations: A Qualitative-Deliberative Approach; SDES-2016-14; Kochi University of Technology: Kochi,
Japan, 2016.
Van Lange, P.A.; De Bruin, E.; Otten, W.; Joireman, J.A. Development of prosocial, individualistic, andcompetitive orientations: Theory and preliminary evidence. J. Pers. Soc. Psychol. 1997, 73, 733–746.
[CrossRef]
Saito, M. Does a present generation change its own preferences as a consequence of a discourse withimaginary future generations? Trends Sci. 2018, 23, 16–19. (In Japanese) [CrossRef]
Shahrier, S.; Kotani, K.; Saijo, T. Intergenerational sustainability dilemma and the degree of capitalism insocieties: A field experiment. Sustain. Sci. 2017, 12, 957–967. [CrossRef]
Shahrier, S.; Kotani, K.; Saijo, T. Intergenerational Sustainability Dilemma and a Potential Solution: Future Ahead
and Back Mechanism; SDES-2017-9; Kochi University of Technology: Kochi, Japan, 2017.
Shahen, M.E.; Kotani, K.; Saijo, T. How Do Individuals Behave in the Intergenerational Sustainability Dilemma?
A Strategy Method Experiment; SDES-2020-1; Kochi University of Technology: Kochi, Japan, 2020.
Katsuki, S.; Hizen, Y. Does Voting Solve Intergenerational Sustainability Dilemma? Sustainability 2020,12, 6311. [CrossRef]

Sustainability 2020, 12, 6467

43.
44.

45.

46.
47.
48.
49.

50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.

61.
62.
63.

64.
65.
66.
67.
68.

20 of 21

Hauser, O.P.; Rand, D.G.; Peysakhovich, A.; Nowak, M.A. Cooperating with the future. Nature 2014, 511,
220–223. [CrossRef]
Timilsina, R.R.; Kotani, K.; Nakagawa, Y.; Saijo, T. Concerns for Future Generations in Societies: A Deliberative
Analysis on Intergenerational Sustainability Dilemma; SDES-2018-16; Kochi University of Technology: Kochi,
Japan, 2018.
Nakagawa, Y.; Kotani, K.; Matsumoto, M.; Saijo, T. Intergenerational retrospective viewpoints and individual
policy preferences for future: A deliberative experiment for forest management. Futures 2019, 105, 40–53.
[CrossRef]
Hiromitsu, T. Consideration of keys to solving problems in long-term fiscal policy through laboratory
research. Int. J. Econ. Policy Stud. 2019, 13, 147–172. [CrossRef]
Nakagawa, Y.; Arai, R.; Kotani, K.; Nagano, M.; Saijo, T. Intergenerational retrospective viewpoint promotes
financially sustainable attitude. Futures 2019, 114, 102454. [CrossRef]
McAdams, D.P.; de St. Aubin, E.; Logan, R.L. Generativity among young, midlife, and older adults.
Psychol. Aging 1993, 8, 221–230. [CrossRef]
Hirayama, R.; Kusumi, T. Effect of critical thinking disposition on interpretation of controversial issues:
Evaluating evidences and drawing conclusions. Jpn. J. Educ. Psychol. 2004, 52, 186–198. (In Japanese)[CrossRef]
Saito, M. Realm of Crisis; Keiso-shobo: Tokyo, Japan, 2018. (In Japanese)
Nakagawa, Y.; Saijo, T. Can Individuals Caring Little about Future Generations Serve as Their Representatives?
SDES-2020-9; Kochi University of Technology: Kochi, Japan, 2020.
Shahen, M.E.; Shahrier, S.; Kotani, K. Happiness, generativity and social preferences in a developing country:
A possibility of future design. Sustainability 2019, 11, 5256. [CrossRef]
Kamijo, Y.; Hizen, Y.; Saijo, T.; Tamura, T. Voting on behalf of a future generation: A laboratory experiment.
Sustainability 2019, 11, 4271. [CrossRef]
Demeny, P. Pronatalist polices in low-fertility countries: Patterns, performance, and prospects. Popul. Dev.
Rev. 1986, 12, 335–358. [CrossRef]
Kamijo, Y.; Tamura, T.; Hizen, Y. Effect of proxy voting for children under the voting age on parental altruism
towards future generations. Futures 2020, in press. [CrossRef]
Hizen, Y. The future design of political institutions. Trends Sci. 2018, 23, 49–51. (In Japanese) [CrossRef]
Hiromitsu, T. Approaching the long-term public finance problem using ethics and experiments—A newdevelopment in future design. Trends Sci. 2018, 23, 24–27. (In Japanese)
Saito, Y.; Kameda, T. The possible role of senior citizens for achieving the intergenerational equity. Trends Sci.
2018, 23, 31–33. (In Japanese) [CrossRef]
Kobayashi, K. Economics of Time: Freedom, Justice and Revenge of History; Minerva: Tokyo, Japan, 2019.
(In Japanese)
Kobayashi, K. Economic growth and the new social contract. In After the Collapse of Public Finances:
Crisis Scenario Analysis; Kobayashi, K., Ed.; Nikkei Publishing Inc.: Tokyo, Japan, 2018; pp. 251–291.
(In Japanese)
Rawls, J. A Theory of Justice; Harvard University Press: Cambridge, UK, 1971.
Calvo, G. Some notes on time inconsistency and Rawls’ maximin criterion. Rev. Econ. Stud. 1978, 45, 97–102.
[CrossRef]
Klaser, K.; Sacconi, L.; Faillo, M. Climate Change and Intergenerational Social Contract: Insights from a Laboratory
Experiment in Rawlsian Perspective; CEEL Working Paper 3–20; Cognitive and Experimental Economics
Laboratory: Trento, Italy, 2020.
Wolf, S.; Dron, C. The effect of an experimental veil of ignorance on intergenerational resource sharing:
Empirical evidence from a sequential multi-person dictator game. Ecol. Econ. 2020, 175, 106662. [CrossRef]
Smith, A. The Theory of Moral Sentiments; Penguin: London, UK, 2010.
Hiromitsu, T. Regarding the philosophical basis of the future generation problem. Finance 2015, 51, 27–47.
(In Japanese)
Rawls, J. Political Liberalism; Columbia University Press: New York, NY, USA, 1993.
Hume, D. A Treatise of Human Nature; Dover Corporation: New York, NY, USA, 2003.

Sustainability 2020, 12, 6467

69.

70.

71.

72.
73.
74.
75.
76.
77.
78.
79.

80.
81.
82.
83.
84.
85.
86.
87.

21 of 21Hara, K.; Yoshioka, R.; Kuroda, M.; Kurimoto, S.; Saijo, T. Reconciling intergenerational conflicts withimaginary future generations—Evidence from a participatory deliberation practice in a municipality inJapan. Sustain. Sci. 2019, 14, 1605–1619. [CrossRef]
Nakagawa, Y.; Hara, K.; Saijo, T. Becoming Sympathetic to the Needs of Future Generations: A PhenomenologicalStudy of Participation in Future Design Workshops; SDES-2017-4; Kochi University of Technology: Kochi,
Japan, 2017.
Hara, K.; Sugino, H.; Takeda, H.; Saijo, T.; Kitakaji, Y.; Yoshioka, R.; Hizen, Y. Effects of Experiencing the Role of
Imaginary Future Generations in Decision-Making—A Case Study of Participatory Deliberation in a Japanese Town;
RIETI Discussion Paper Series 19-E-104; RIETI: Tokyo, Japan, 2019.
Yoshioka, R. Future design in Yahaba. Trends Sci. 2018, 23, 10–12. (In Japanese)
Nishimura, N.; Inoue, N.; Masuhara, H.; Musha, T. Impact of future design on workshop participants’ time
preferences. Sustainability 2020, in press.
Nakagawa, Y.; Saijo, T. Visual narrative for taking future generation’s perspective; SDES-2020-8; Kochi Universityof Technology: Kochi, Japan, 2020.
Nakagawa, Y.; Saijo, T. Future Design as a metacognitive intervention for presentism. Sustainability 2020,
in press.
Nakagawa, Y. Taking a future generation’s perspective as a facilitator of insight problem-solving: Sustainable
water supply management. Sustainability 2020, 12, 1000. [CrossRef]
Nakagawa, Y.; Saijo, T. Designing post-corona worlds. In Economics of Corona Crisis; Kobayashi, K.,
Morikawa, M., Eds.; Nihon Keizai: Tokyo, Japan, 2020; in press.
Kurashiki, T. Risk communication based on future design. Trends Sci. 2018, 23, 42–45. (In Japanese) [CrossRef]
Uwasu, M.; Kishita, Y.; Ara, K.; Nomaguchi, Y. Citizen-participatory scenario design methodology with
future design approach: A case study of visioning of a low-carbon society in Suita city, Japan. Sustainability
2020, 12, 4746. [CrossRef]
Takeda, H.; Sugino, H. Future design utilization for community development through citizen participation.
Trends Sci. 2018, 23, 46–48. (In Japanese) [CrossRef]
Matsunaga, C.; Managi, S. Inclusive wealth index and policy decision. Trends Sci. 2018, 23, 60–63. (In Japanese)[CrossRef]
Hayek, F.A. The use of knowledge in society. Am. Econ. Rev. 1945, 35, 519–530.
Scott, J.C. Two Cheers for Anarchism: Six Easy Pieces on Autonomy, Dignity, and Meaningful Work and Play;Princeton University Press: Princeton, NJ, USA, 2012.
Principles of Future Design Practice. Available online: http://www.souken.kochi-tech.ac.jp/seido/practice/information/principlesinpractice.html (accessed on 20 June 2020). (In Japanese).
Kant, I. Perpetual Peace: A Philosophic Essay; Benjamin, F., Translator; Trueblood; The American Peace Society:
Boston, MA, USA, 1897; p. 46.
Aoki, R.; Ito, A.; Izuma, K.; Saijo, T. How Can Neuroscience Contribute to the Science of Intergenerational
Sustainability? SDES-2020-11; Kochi University of Technology: Kochi, Japan, 2020.
Kobayashi, K. A study of intergenerational bubbles for sustainability. Sustainability 2020, in press.
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