A human being begins as a microscopic fertilised egg-cell, within which
there is condensed the long result of time--Man's inheritance. The long
period of nine months before birth, with its intimate partnership
between mother and offspring, is passed as it were in sleep, and no one
can make any statement in regard to the mind of the unborn child. Even
after birth the dawn of mind is as slow as it is wonderful. To begin
with, there is in the ovum and early embryo no nervous system at all,
and it develops very gradually from simple beginnings. Yet as mentality
cannot come in from outside, we seem bound to conclude that the
potentiality of it--whatever that means--resides in the individual from
the very first. The particular kind of activity known to us as thinking,
feeling, and willing is the most intimate part of our experience, known
to us directly apart from our senses, and the possibility of that must
be implicit in the germ-cell just as the genius of Newton was implicit
in a very miserable specimen of an infant. Now what is true of the
individual is true also of the race--there is a gradual evolution of
that aspect of the living creature's activity which we call mind. We
cannot put our finger on any point and say: Before this stage there was
no mind. Indeed, many facts suggest the conclusion that wherever there
is life there is some degree of mind--even in the plants. Or it might be
more accurate to put the conclusion in another way, that the activity we
call life has always in some degree an inner or mental aspect.
[Illustration: OKAPI AND GIRAFFE
The Okapi is one of the great zoölogical discoveries. It gives a good
idea of what the Giraffe's ancestors were like. The Okapi was unknown
until discovered in 1900 by Sir Harry Johnston in Central Africa, where
these strange animals have probably lived in dense forests from time
immemorial.]
In another part of this book there is an account of the dawn of mind in
backboned animals; what we aim at here is an outline of what may be
called the inclined plane of animal behaviour.
A very simple animal accumulates a little store of potential energy, and
it proceeds to expend this, like an explosive, by acting on its
environment. It does so in a very characteristic self-preservative
fashion, so that it burns without being consumed and explodes without
being blown to bits. It is characteristic of the organism that it
remains a going concern for a longer or shorter period--its length of
life. Living creatures that expended their energy ineffectively or
self-destructively would be eliminated in the struggle for existence.
When a simple one-celled organism explores a corner of the field seen
under a microscope, behaving to all appearance very like a dog scouring
a field seen through a telescope, it seems permissible to think of
something corresponding to mental endeavour associated with its
activity. This impression is strengthened when an amoeba pursues
another amoeba, overtakes it, engulfs it, loses it, pursues it again,
recaptures it, and so on. What is quite certain is that the behaviour of
the animalcule is not like that of a potassium pill fizzing about in a
basin of water, nor like the lurching movements of a gun that has got
loose and "taken charge" on board ship. Another feature is that the
locomotor activity of an animalcule often shows a distinct
individuality: it may swim, for instance, in a loose spiral.
But there is another side to vital activity besides acting upon the
surrounding world; the living creature is acted on by influences from
without. The organism acts on its environment; that is the one side of
the shield: the environment acts upon the organism; that is the other
side. If we are to see life whole we must recognise these two sides of
what we call living, and it is missing an important part of the history
of animal life if we fail to see that evolution implies becoming more
advantageously sensitive to the environment, making more of its
influences, shutting out profitless stimuli, and opening more gateways
to knowledge. The bird's world is a larger and finer world than an
earthworm's; the world means more to the bird than to the worm.