30 Sketch of a General Theory of the (Jury, 
intermediate, and the cerebellum the last.—For, although the face, 
containing the organs of sense, and the cerebellum, are, in different 
animals, very differently placed with regard to the cerebrum, yet 
there is a peculiar relation between the situation of one of these and 
that of the other with regard to it, In other words, although the 
face is sometimes in one situation and sometimes in another with 
relation to the cerebrum, yet to each given variation of its situation 
with regard to that body there is a corresponding and uniformly 
accompanying variation in the situation of the cerebellum. Thus 
as, in man, the face is placed below the anterior part of the cere- 
brum, so is the cerebellum placed below its posterior part ; and 
precisely as, in the inferior animals, the face advances, precisely so 
does the cerebellum recede, till, in those animals in which the face 
is placed exactly before the cerebrum, the cerebellum is placed 
exactly behind it.* 
4. Of the functions, sensation is the first, mental operation in- 
termediate, and volition the last.—'That sensation precedes and ex- 
cites, if it do not generate, mental operation, few will deny: that 
mental operation, however rapid or evanescent, precedes and ex- 
cites volition, or that the motive to an action must precede the 
action, none will refuse: and that, of any one series of intellectual 
action, volition is the last stage, all must admit. 
5. As, then, the cerebellum is the last of the intellectual organs, 
and volition the last of the intellectual functions, and as, at the 
same time, there is no organ without function, or function without 
organ, it follows, that the cerebellum must be the organ of volition. 
6. In perfect conformity with this truth, the inferior animals, 
however defective in intellect, possess motion; and, in almost all 
of them which have any visible nervous system, a cerebellum, the 
organ of that motion, exists—This leads me to an observation 
which seems to me to possess considerable interest and beauty. As 
we descend among animals, one of the three portions of the nervous 
system and one of its three general functions gradually disappear. 
Now it is not the first and the last portions of the nervous system— 
it is not the organs of sense and the cerebellum, neither is it their 
respective functions, sensation and volition, which are thus lost, It 
is the cerebrum and mental operation which are. This organ is, 
among men, most conspicuous in the Caucasian race; and we 
accordingly find that that race alone has cultivated the sciences. It 
is less even in the Mongal and Ethiop, who have ever disregarded 
them. Jt gradually disappears and ultimately evanishes as we 
descend among quadrupeds, birds, reptiles, fishes, &c. and with it 
gradually disappear and ultimately evanish the powers of thought. 
But organs of sense and a cerebellum,—sensation and volition, yet 
remain to characterize myriads of animals below these. 
' 
* The cerebellic cavity, moreover, seems uniformly to commence on the inside 
of the base of the cranium exactly opposite to the place where the face, or the 
lower jaw, terminates on the outside. 
