, 1873-05-25
z Lecture by Prof. Agassiz.
The Mental Powers and Their Dis
tribution Among Animals.
Possibility Of Insects Possessing an
Utterly Different Kind Of
Intelligence.
The Brains Of Fishes---A Brief
Sketch of the Radiates.

Cambridge, Mas, <Hay 1s Correspondence Of the few
i. FORK Tribune. 49,. - Z
The following lecture Was delivered by Prof.
Agassiz, on the 1st inst, At the Museum Of Com
parative Zoology: -
From the highest antiquity the mental powers
Of man have been subject for the study and
meditation Of philosophers :. MetaphyBicians
have considered this field of investigation as ex-
cluslyely and essentially their own, and have
looked with jealousy upon any attempts to deal
with the subject from another point Of view.
With the revival OF learning, however, in the
ei1teenth century, natu1alists began to consider
the manifestations Of mental energy in animals
with reference to their structure From that
time forward research has taken . new
direction; psychology and. physiology, have
been studied together; it has been rec
csnized that the action Of tho mental
power, both in men and animals, is more
or less connected with their structural organiza-
ton. It is impossible in our day to discuss any
zRetaphysical questions, except in come ction
HAkh certain organs in the living body, without
EEich mental manifestations ara impossible. /
SEhau not say, nor do believe, that the mental
faculties arc product Of these organa but
will say what, indeed, every observing man must
acknowledge, ':thAt without brain you have no
thinking without brain You have NO expression
sof intellectual power :: without certain struc-
tufe. no manifestation even Of those, in
stinctive faculties characteristic Of the lower
tms1s is possible In the structure, with the
structure, through the structure do these pow
ers act and it is by the study Of structure in
connection with these powers that we may; hope
to learn something Of their true nature. I do
not mean to say that intellectual processes may
not be considered BY themselves from purely
metaphysical point Of view, but we are led more
and more to consider the structure Of the Or
gans through which the mind acts as IN essen
tial part Of the subject. Anatomy and physiol-
ogy are the natnral: aasoclates Of metaphysics,
&nd must be taken into partnership, whether the
logicians like it or not; unless, indeed; they are
contented to rehearse the traditional spcculao
tions Of philosophy in past ages. r.
ARE TIE MENTAL FACULTIES oSE2 49,.
There is another way Of approaching the sub~
jcct which has it's great value. The wisdom Of
the human race is consolidated Us it were in Ian
guage. Thus men have consciously or uncon-
sciously preserved the best results of their men
tal Efforts or the spontaneous expression OF their
natural mental gifts. By careful comparison
Of languages, aud even of isolated words, we
may form some idea OF the estimate men them
through all ages. Different nations have by no
MEANS the ssme richness Of Expression to desig-
nate these faculties; and :. some nations
make nice distinctions between special
mental spoWers which others do not recognize.
The Germans give the names yerstand and YER
nunft 10 two sidesot ourmental powers, meaning
By tho former the reflective, argumentative, |
combining power, which ne 1nav translnte'as in /
telleet, intelligence, reason !; and BY the latter
the unconscious, spontaneous action Of mental |
f{%oY f1osn
and combination which belongs to con-
Ecious intellectual effort. Our English word |
Intelligence renders perfectly the German yer |
stand; but sense, unless We qualify it as good
eense. or judgnent-that quality in abort, which |!
takes cognizapce Of and guides our daily Iyes |
without conscious effort, hnrdly translates the |
German uernunN. This is not the place nor |
have the knowledge to follow this kind Of j. |
lustration. allude to it only because tho COM
parative value and significance Of words has a |
irrge share in the Investigation of mental quail
ties and their expression. |
Are all mental faculties one7 Ia there only |
one kind Of montal power throughout the whole
animal kingdom differing only III intensity and |
bic lectures given lately in Boston BY DR.. Brown
Sequard, he laid before .his audience q new
philosophy of mental powers Through phyalo- |
logical experiments combined with = care |
full study and comparison Of pathological |
rasee, he has come to tho conclusion that !
powers in the human organization, or acting
through the human organism, essentially differ /
ent from the other. The one may be designated !
as one Ordinary conscious intelligence the 9TH
q as superior power which controls cur bet
er nature. solSes,: sometimes suddenly and m
s1pected1y, my. eyan in sleep, our problem and
perpe1:tss, suggests the right thing at tlle right
lime, acting through us without conscious &C.
lon Of our own, Though susceptible Of training
md elevation Or perhaps. I should rather ssY
our own organism may be trained to mora
Elastic instrument through which this power
acts III u.s. .. ...,... .....,.. |
MENTAL FACULTIES OF ALL TERTEBRATEs SIMILAR.
do not see Why this view should not be ac-
:epted. It is in harmony with facts as lar as
re knoT them. The experiments through
which my friend Dr.. BroWn-Sequard has eatis-
led himself that the subtle mechanism Of the |
human fTamo about. which we know so little in |
ts connection NTH mental processes; is some
lines acted upon by I power outside of 1s rs ia
uiiiar Eith that Organization as ne are ignorant