DECEMBER 24, 1897.] 
entirely new; and therefore, also, so far as 
I am aware, no experiments directly bear- 
ing on it have been made. Moreover, in the 
highest animals all acquired physical char- 
acters are merely extensions of previously 
existing inborn characters. Thus the limb 
of an infant, which is compounded, as we 
may suppose, almost entirely of that which 
is inborn, grows under the influence of ex- 
ercise and use into an adult limb. There 
is a Sharp dividing line, but we cannot per- 
ceive it; and, therefore, as regards the in- 
fant’s limb, we cannot as yet say where the 
inborn ends and the acquired begins. But 
in mind, which we have next to consider, 
the case is often very different. There the 
inborn is often sharply marked off from the 
acquired, and we shall find it emphatically 
true that low animals are infinitely less 
eapable of acquiring mental traits than 
high animals. Whence, reasoning by anal- 
ogy, we may, with some confidence, assert 
that if, as regards mind, the statement is 
true, in the absence of evidence to the con- 
trary, it is probably true also as regards the 
physical parts. 
Mind, doubtless, owes its origin to move- 
ment—to the necessity for coordinated 
movement in the various parts of the com- 
plex cell-community which we call a multi- 
cellular animal. Neither mind nor nervous 
tissue, the organ of mind, exists in plants, 
among which there is little or no move- 
ment. So, also, low in the animal scale, as 
among sponges, in which cells are not co- 
ordinated to perform movements en masse, 
there isno mind nor any need forit. Higher 
in the scale, as among Colenterates, in 
which masses of the cells combine to per- 
form macroscopic movements, we begin to 
find traces of nerve tissue, but as yet there 
is, so far as we are aware, no mind. All 
movement apparently is purely reflex. Yet 
higher in the scale, as among the Mollusca 
in which the increasing complexity of the en- 
vironment necessitates increasingly complex 
SCLENCE. 
935 
coordinated movements of masses of the 
cell-community, the nervous mechanism 
by means of which this codrdination is 
carried out becomes still more developed 
and complex, and mind apparently dawns. 
So far as we know, consciousness then first 
appears, and with consciousness the rudi- 
ments of instinct. 
I have elsewhere defined instinct as ‘‘ the 
faculty which is concerned in the conscious 
adaptation of means to ends by virtue of in- 
born inherited knowledge and ways of 
thinking and acting.’’* In other words, in- 
stinct depends wholly on congenital char- 
acters, and not in the least on those which 
are acquired. This definition of instinct is 
far different from those which have hitherto 
found acceptance, but I think on considera- 
tion it will be found that it more correctly 
describes what we commonly mean by the 
term than any other hitherto put forth. 
By instinctive action do we not mean ac- 
tion which is independent of all previous 
experience and therefore of acquirement? 
When an insect secures its proper food in 
the proper way, spins a cocoon, mates with 
an individual of the opposite sex, or lays 
its eggs, with fit provision for the future, in 
an appropriate place, does it not act solely 
by virtue of inborn inherited knowledge 
and ways of thinking and acting, and, 
since it is unguided by experience, not in 
the least by virtue of knowledge and ways 
of thinking and acting which are acquired? 
To the mind of every naturalist will at once 
occur innumerable instances of actions, 
some of them extremely complex and elab- 
orate, performed by insects and other com- 
paratively low animals, in which experi- 
ence can play no part; in other words, 
which are wholly independent of acquired 
knowledge and ways of thinking and acting. 
By means of instincts animals are enabled 
to place themselves in harmony with an 
environment infinitely more complex than 
* The Present Evolution of Man, p. 137. 
