Islam, Trade, and Innovation
Alireza Naghavi
University of Bologna

This chapter provides a discussion on the of pervasiveness of innovation, or the lack thereof, at different
points of history in the Muslim world. The idea put forth is the interconnection of innovation with trade,and the puzzle is the cease of the former despite the continuation of the latter in the contemporary
world. The first step is to present a brief overview of core Islamic principles that encourage trade but
discourage innovation by the inclusion of property right matters in Islamic law. We then look at thehistorical contribution of trade in uniting the Muslim world and initially triggering innovation andachieving the golden age of Islam. Finally, the chapter suggests reasons why innovation eventually cameto a halt in Islamic lands, including political economy arguments, tolerance, diversity, and institutions.
Introduction
Trade fosters innovation. This is by now a well-established fact in the economics literature. The seminal
theoretical work on trade, innovation, and growth goes back to Grossman and Helpman (1989, 1990)
among others. Theories that follow suggest that trade liberalization essentially affects innovation
through two channels. The first channel is improved access to foreign markets. Higher profits brought
about by a larger market create incentives to innovate (Acemoglu and Linn, 2004). Trade also opens thegate to a more competitive marketplace, which in turn creates a threat to profits and induces firms toinnovate new varieties to continue to benefit from monopoly rents (Aghion, et al., 2005). Grossman andHelpman (2017) also show an adverse effect of competition as successful innovators must share themarket with foreign competitors. They, however, show that the market size effect offsets this negative
effect and that open economies tend to innovate and grow more than closed ones. Furthermore, Coelli,Moxnes, and Ulltveit-Moe (2016) show striking evidence that indeed around seven percent of theincrease in global knowledge over the 1990’s can be attributed to freer trade.
The trade and innovation nexus tends to be absent in the Muslim world today. Naghavi and Pignataro(2018) show that countries with the highest percentage of Muslim population tend to produce thelowest level of patents worldwide. These countries practically include the core of the Islam, or
historically the greater Muslim empire, and consist of Iran, Saudi Arabia, Syria, Tunisia, Egypt, Yemen,
Algeria, Jordan, Pakistan, Morocco, Bangladesh, Tajikistan, Uzbekistan, Turkey, and Sudan. At the sametime, we know that Islam is a religion of trade. Prophet Muhammad was himself a Meccan merchant. A
large part of those involved in the gradual manifestation of Islamic law were also craftsmen or
merchants or at least came from such backgrounds (Cohen, 1970). Also, trade as a profession held amore favored position in the Islamic world than in Europe (Skeen, 2008). Michalopoulos, Naghavi, andPrarolo (2016) argue that trade played a critical role in the formation of Islamic principles. A mainargument they put forth is the role of Islam as an agreement to secure safe passage across the desert
against raids and ensure redistribution required a commitment device to make cooperation between
tribes viable.
Trade and Islamic Principles
Islam is particularly known to have conferred economic benefits to individuals through the institutional
advantages it created by facilitating trade. Michalopoulos, Naghavi, and Prarolo (2016) describe the roleof the waqf as a dynamic redistribution system that spread wealth inter-generationally and stalled its
concentration, making Islam work as a self-enforcing cooperation treaty that unified tribes of different
natures into an Islamic community. Ensminger (1997) offers case studies comparing trade within Muslim
and non-Muslim indigenous African societies, stressing how the institutional guarantee of Islam
provided an additional impetus for trade by facilitating the flow of credit. An important advantage ofIslam with respect to previous arrangements was the fact that it offered a powerful ideology with builtin sanctions that created non-material interest in holding to the terms of contracts. The existence of
informal and formal punishments in Islam, such as those related to ridda (apostasy), gave Islam an edge
over similar pre-existing, short-lived attempts. Although the focus of Michalopoulos, Naghavi, andPrarolo (2016) was the mitigation of conflict between trading merchants and Bedouin tribes in arid lands
though the Islamic institutional complex, a reduced form variant of the theory can be used to illustrate
the role of Islam as a commitment device in the following game.
Think of merchants travelling on trade routes who must cross the desert and the possibility of theircaravans being raided by Bedouins, who lack merchandise to engage in long-distance trade themselves.
A confrontation between the trading caravan and the Bedouins may take place in the desert and resultof a loss of their cargo. There is, however, the possibility of redistributing a part of the potential profits
from trade to the Bedouins. An agreement could be made between the two sides to furnish a
redistribution of rents from those who can benefit from trade to the less-advantaged portion of thesociety and secure safe passage across the route. It is easy to show a game, in which the uniquesubgame perfect Nash equilibrium would be to not redistribute by the merchants and raid by the
Bedouins, resembling a prisoner’s dilemma interaction where both sides end up in a socially inefficientequilibrium. This situation illustrates why the pre-Islamic redistribution attempts between tribes in the
Arabian Peninsula, such as the case of ilaf, were temporary, highlighting the need for a credible
commitment device to achieve the socially efficient outcome. This was the role played by Islam as areligion. Indeed, the terms of Muhammad’s agreements with the tribes were always the same: the tribe
agreed to pay the zakat and to refrain from attacking other Muslims and their allies (Lewis, 1993).
Adding an apostacy cost or, in general, a cost of deviating from Muslim law that proposes a(Redistribute, Not Raid) equilibrium serves as a credible punishment device to make the cooperative
solution the unique equilibrium outcome which could also be Pareto optimal.
Intellectual Property and Islamic Law
The mechanism is not the same, if not the opposite, with innovation in Islam. Naghavi and Pignataro(2018) highlight how it is exactly the fundamentals in Islamic principles that could lead to the demise ofinnovation in Muslim countries. This occurs due to the existence of a fallacy with respect to theprotection of intellectual property in Islamic law. Although the concept of protection is moreemphasized in Islam than other religions, the enforcement is left to the morality of the agents in thesociety creating a situation of adverse selection. The intellectual property environment is different inother religions, where legal institutions rather than religious scripts take charge in enforcing intellectual
property rights.
The Sharia law includes clauses that resemble modern intellectual property considerations. The Caliphs
in early Islam for example bought books and only made copies after paying an adequate compensation
to the author (Malkawi, 2013). Indeed, Sharia draws close connections between intellectual property
and Islamic law, albeit not explicitly regulating intellectual property rights with precise rules as it does
for tangible property rights. In short, ownership of property can be acquired by appropriation, underwhich one may acquire ownership by developing it and making it productive to reward individuals forthe fruits of their effort. The Sharia text does not limit such ownership to tangible assets, and is hencecompatible with offering economic incentive to intellectual property owners by entitling them to
exclusive right to enjoy the benefits of their creativity.
Nevertheless, the prohibition of intellectual property rights piracy in Islam has been limited to the
Muslim judges’ use of qiyas, though without a clear punishment such as that for material theft. An

interesting analogy regarding the separation of tangible and intangible assets in Islam lies in the Hedaya,
which suggests that one does not amputate the hand of a thief for stealing a book because the thief's
intention is not to steal the book as paper, but the ideas in the book, which is not tangible property (AlMarghinani, 1791). The existence of this gray area when partial enforcement is left to Sharia has
impeding consequences for business relationships and investment incentives that are key for innovationand economic development. Naghavi and Pignataro (2018) show that formal enforcement of intellectual
property rights through legal institutions that are not linked to religious guidance could break the fallacy
that emerges in a world of asymmetric information by encouraging moral agents to engage intechnological effort in sectors less sensitive to intellectual property rights, while preventing
expropriation by the amoral agents in sectors with more valuable technologies.
Trade as the Powerful Gravity of Islam
Michalopoulos, Naghavi, and Prarolo (2018) provide evidence that a main factor in the fast andexpansive spread of Islam was the interests of merchants who wanted to gain access to the widest
possible network of trade routes. Indeed, they show Islam predominantly spread across trade routes in
the Old World. They argue that after the initial phase of the expansion of Islam throughout the first
century after its birth within a certain radius around Mecca through military conquests, the religion
gained control over a vast strategic location from North Africa passing through the Middle East all theway to the Indian sub-continent. This put the Islamic region in the center of a network of the mostimportant traditional trade routes that connected the Old World and included the whole Western half of
the Silk Road. It also linked maritime trade of the Mediterranean and the Indian Ocean. Merchants in
those regions therefore had extra incentives to adopt the religion to gain advantages via cooperationand favorable laws reserved only within Muslim trading networks and access to valuable contacts to
expand their trade. Islam at the same time spread along trade routes through propagation as Muslims
themselves travelled long-distance along the routes when they engaged in trade.
It is likely that trade and innovation went together and reinforced each other in the advent of Islam,during the flourishing years of the Muslim territories. The Islamic empire stretched from Spain to theborders of China in inner Asia, creating a unique unified economic region, facilitating movement of not
only merchants and goods, but also craftsmen and scholars. The ease of trade in the Islamic also allowed
new ideas, techniques, and inventions to travel freely. Skeen (2008) provides a simple example of a rug
made in China, that could be traded as far as Algeria within a year, and the technique of its manufacturecould be copied by local craftsmen. Last, but not least, trade also nurtured a swift movement of books
across the Islamic world.
The Big Bang and the Big Crunch of Innovation in the Islamic World
Science and technology in the medieval Muslim world surpassed that in the West and China by far (Huff,
2003). Several very practical and important innovations took place during the golden age of Islamic
civilization under the Abbasid dynasty, especially in agriculture. Improved methods of irrigation allowed
more land to be cultivated, and new types of mills and turbines were used to reduce the need for labor.
The cultivation of rice and the production of textile were among major innovations of the era. Crops andfarming techniques were adopted from remote neighboring cultures such as India, China and Africa.
Islamic famers contributed to eventually bringing crops such sugar and citrus fruits to the West, anddistributing the cultivation of cotton to Iraq and Egypt (Wilson, 1983). Major scientific inventions
associated with the Abbasids were also in fields of mathematics algebra, geometry, science, astronomy,
medicine, anatomy.

In medicine, the 9th century saw over 800 doctors in Baghdad, and many

discoveries with regards to anatomy and diseases were achieved. Also, the invention of techniques tomake thicker, more useful paper was an achievement of Baghdad (The Saylor Foundation, n.a.; Syed, etal., 2011).
The reborn Umayyad caliphate in Córdoba, after being overthrown by the Abbasid revolution and theirrelegation to Al-Andalus of Spain, also represented a peak of scientific and artistic achievements of the
Muslim world. The Umayyads wanted to be seen as intellectual competitors of the Abbasids who led totheir collapse, and pushed Córdoba to have libraries and educational institutions to rival those of
Baghdad. Despite the rivalry between the two powers, which created competition, freedom to travel
between the two Caliphates was allowed and helped spread fresh ideas and innovations over time.
There was, however, a radical switch in the link between Islam and innovation in the aftermath of the
Umayyads. This occurred when smaller unstable independent Taifas first took power for about 50 years,
after which they were forced to call for the help of North African (Berber) caliphates. The Almoravids
came to their rescue but soon took control themselves, and where succeeded by the Almohads. Thesedynasties were more aggressive, and at the same time more unstable (and hence under threat), lasting
70 years each and losing more and more territory over time during the Reconquista period. In principle,
they were more of a ruling military elite in al-Andalus than intellectuals. Under the Almoravids andAlmohads there was a decline in cultural and social exchange and increased persecution of religious
minorities, with a switch to more fundamentalist forms of Islam (Jayyusi, 1994).
Innovation as a Sacrifice for PowerThe great economic divergence described in depth in Kuran (2010) has been related to the nature ofIslam discouraging curiosity and preventing risk-taking activities by the Muslim society. In line with thenarratives on religion and science in medieval Spain, Cinnirella, Naghavi, and Prarolo (2018) look directly
at intellectual achievements in Spanish municipalities based on the number of years they have been
under Muslim rule. Looking at literacy rate in 1900 and the number of historical patents achieved during
the period of 1878-1939 in each municipality, they find that both measures of human capital orinnovation are lower for municipalities that have been under Muslim rule for a longer period. There areseveral factors and historical narratives that can explain the negative correlation between religion, or
particularly Islam, and innovation. I pick three recent interrelated analyses that are relevant for theargument in this chapter and provide a brief description of each below.
A recent analysis on the potential role of Islam in impeding innovation comes in Chaney (2016).
Collecting data on intellectual production (from Harvard’s library collection and a catalog of books from17th century Istanbul) he establishes that Islamic societies flourished with scientific and technologicalproduction in the medieval period, but produce a disproportionately small share of world scientificoutput today. He focuses on the Sunni Revival, namely the 11th century surge in political power ofreligious leaders, as the decisive historical landmark. The hypothesis argues that increased politicalpower came together with a replacement of scientific institutions that contributed to human capitaldevelopment with religious educational centers such as madrasas. The elite promoted religious
institutions as centers of knowledge production by requiring scholars to specialize in religious
knowledge as a prerequisite to being appointed to any posts. This reduced the payoff to the productionof scientific knowledge and shifted preferences in favor of production of religious knowledge. The
evidence revolves around the newly empowered religious leaders and how they intentionally limited the
production of scientific knowledge to avoid tampering with religious beliefs in society. The hypothesis is
in line with previous argument in Mokyr (2002) that human capital formation and religion can beinterrelated. In this context, we are talking about a political economy setting where religious elites
believe that human capital accumulation could weaken their grip on power and control over the
population.

Bènabou, Ticchi, and Vindigni (2015) is another contribution in literature that refers to the clash
between innovation and religious doctrines in general. They show that the number of patents filed isdecreasing in both religiosity and belief in god both across countries and across US states. Here theblame goes to a state that incorporates religious rule, which may repress new discoveries to protect
religious beliefs. The model provided views that the diffusion of scientific discoveries brings productivity
gains, but also neglect religious beliefs by contradicting the doctrine. The key mechanism suggested inthis study is the potential belief-eroding characteristic of innovation. The government can impede
innovation from spreading by blocking the spread of belief-eroding science. Muslim authorities started
perceiving innovations as a potential threat in the beginning of the 12th century; the anti-science
attitudes are still observable in the Muslim world today. The most striking case of knowledge blocking in
the case of Islam is the decree in the Ottoman Empire that ruled the practice of printing punishable bydeath until the beginning of the 19th century.
Muslim religious authorities used their political power to advocate laws that inhibited economic
development, such as regulations that inhibited the spread of knowledge (against printing press) andhuman capital development (against mass education). Conservative Islamic clerics in the background
who enjoyed a strong political seat saw such important advancements as a threat to their power, andthe state which was strongly tied to religion, saw it in their own interest to rule in their favor (Rubin,2017). The crux of the argument behind the Muslim anti-printing attitude has been described to be thereliance of political authorities under Islam on legitimacy by religious authorities, the attainment of
which depended on their conforming to the corresponding religious rules. This environment reduced
enthusiasm for introducing novel technologies, including the printing press (Coşgel, Miceli, and Rubin,2012). More specifically, the power of religious authorities depended on their role in the transmission ofknowledge, an essentially oral process in early Ottoman society prior to the introduction of the printingpress. Skepticism in Islam with regards to unsupervised writings as reliable means of communication
granted religious authorities a monopoly position in the transmission of knowledge. They used theirposition to provide Ottoman rulers with legitimacy by producing loyalty, in return for compensations
such as the incorporation of religious institutions into the state. Ottoman rulers banned printing because
they believed it may undermine the comparative advantage of religious authorities to confer legitimacy,
thereby increasing the costs of tax collection. The Ottomans eventually granted permission to printing in
Arabic script in the 18th century only upon the emergence of new sources of legitimacy (Rubin, 2017).

The Missing Role of Tolerance
Tolerance is a concept often associated with the impact of religion on innovation. The argument on
tolerance is not confined to Islam, but works for any belief by creating diversity and synergy between
diverse people (Cinnirella and Streb, 2017). The Muslim empire is known to have been tolerant towards
followers of other religions (Lapidus, 2002). Also, the output of Arab science during the golden age ofIslam shows that there is no fundamental barrier to tolerance and progress in the Islamic world (Ofek,
2011). Iyer, Tucku, and Shrivastava (2017) show that even when Muslims were engaged in destroying
holy sites of other religions, they did not oppose their presence. The unique evidence found in theirresearch shows that Muslims desecrated temples to diminish the authority of the enemy, the Hindu
state, during war.
Interestingly, Jha (2013) shows that a factor that has led to religious tolerance in Islam is trade. Due toadvantages enjoyed by Muslims brought about by full control over Indian Ocean shipping, ethnic
complementarities between them and Hindus for exchange and provision of services were highest in
medieval trading ports. This led to development of institutional mechanisms that supported interethniccooperation, and reduced probability of riots and violence between different ethnic groups of the tworeligions. The role of trade on religious tolerance has also been given several alternative compatible
explanations. Clingingsmith, Khwaja, and Kremer (2009) for instance, connects tolerance to Islam
through the role of the Hajj pilgrimage, a pillar of Islam. Their study argues that a global gathering as
such creates unity within an Islamic world through exposure to global Islamic practices, with a spilloverof increased belief in peace, harmony, and equality among adherents of different religions. This concept
indirectly links with trade and innovation as Hajj gatherings also facilitated economic trade and the
diffusion of economic, cultural, and scientific ideas (Bose, 2006).
Then why has a tolerant Muslim religion led to the great economic divergence with respect to adherentsof other religions? As mentioned above, a switch in the level of religiosity and its view of new inventions
could have taken place after the start of the Crusades. Once again, an environment of war may havechanged the perspective of Muslims and led to a less tolerant version of Islam (Gutas, 1998). This may
have also led to intolerance in other religions towards Islam, and hence reduced diversity and interreligion interaction. An example of this is the reduced human capital and innovation in areas of Spain
longer exposed to Islam after the periods of Reconquista that was accompanied by forced conversions
and expulsion of Muslims (Cinnirella, Naghavi, and Prarolo, 2018). As for countries with a Muslim

majority today, Bosker, Buringh, and van Zanden (2013) relate the economic and intellectual stagnationof the Muslim world to reasons not related to tolerance, namely a different choice of main transportmode (camel versus ship) and failure to develop local participative governments as in Europe that madecities less dependent on centralized decision-making states. They show that Islamic lands failed to keep
up with the rest of the world as the methods of trade and urbanization eventually limited potential for
growth. This is in line with Michalopoulos, Naghavi, and Prarolo (2016), who argued that Islamicprinciples designed to limit wealth inequality and escape a state of constant feuding blocked theaccumulation of capital indispensable for growth in the era of large-scale shipping trade andindustrialization.
Conclusion
Theory and empirical evidence in the economics literature has reached consensus that trade andinnovation reinforce each other in nurturing development. Although this was also observed throughout
the Muslim world in its flourishing years of the preindustrial era, innovation in Islamic countries whose
economies continue to be based on commerce is lagging behind with respect to the world technology
frontier. Historical narratives that have also been recently put to data show that trade has been acatalyst for the spread of Islam. The golden age of Islam some of the most important inventions inhistory. The progress in the Muslim world however came to a halt, even if trade continued to be thecore instrument in the further spread of to Sub-Saharan Africa, Inner Asia, and East and Southeast Asia.
A number of studies relate the interruption in innovation and growth in Islam to the behavior of theruling elite to maintain power and rent, and the influence of religion in the state. Lack of religious
tolerance and diversity of ethnic groups and ideas are often blamed for the lack of enthusiasm in thesociety for innovation, though evidence has shown Islam to be a tolerant religion towards other beliefs.
Some recent works have also linked the lack of technological progress to the gaps and fallacies withregards to intellectual property in Islamic law, and even their choice of transport, or the centralization of
the state as opposed to powerful smaller local governments that for example emerged in Europe.
Despite several recent empirical analyses that support alternative explanations of the relationshipbetween Islam, innovation, and trade, economic research on this front is in its infancy and we call forfurther in-depth study of the issue.

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