§ 4. Persistency with Varied Effort. — Even in the earliest performance of its instinctive activities, viz. those activities for which it is predisposed and preadapted by the inherited constitution of its nervous system, an animal may display persistency with varied effort. It keeps on trying when it does not succeed at first, varying its procedure so far as it is unsuccessful. Professor Lloyd Morgan gives a good example, communicated by Mr. Batchelder. Mr. Batchelder had taken squirrels from their nest when they were very young; they were at first unable to take solid food, and had to be fed through a quill on a mixture of cream and hot water. Afterwards they took to bread and milk, biscuits, and bread crusts. Mr. Batchelder then gave them some hickorynuts. "They examined the nuts attentively, evidently looking upon them as unusually interesting novelties, and at last the more enterprising of the two set to work on a nut, as if he wished to find out what prize it might contain. With hitherto unexampled patience he laboured over it, until at last, after more than half an hour's diligent gnawing, he gained access to the kernel. With a few days' practice they acquired skill and speed in extracting these hardshelled delicacies; and after that they lost all interest in such things as biscuits, and hickorynuts formed the principal item on their bill of fare."* Persistency with varied effort also shows itself in more indefinite ways. "I have noted it," says Lloyd Morgan, "again and again in the case of young birds. It was especially noticeable in jays. Every projecting bit of wire or piece of wood in their cage was pulled at from all points, and in varied ways. Every new object introduced into the cage was turned over, carried about, pulled at, hammered at, stuffed into this corner and into that, and experimented with in all possible ways."+

Obviously, persistency with varied effort is a precondition of learning by the results of bygone experience, and not merely a consequence of it. In itself it is an adaptation to present experience rather than to past. Further, it is an adaptation which can only be understood by reference to the continuous impulse or conation which pervades and constitutes perceptual process. Just because the impulse is a tendency towards an end, it guides the course of the action. When the action enters into a phase which checks instead of furthering the return to equilibrium, the current of activity diverts itself into a relatively new channel. The process would not be a process towards an end, if it could persist without variation in an unsuccessful course.

* Habit and Instinct, p. 122.                    Op. cit., p. 154.