to obey impulses of a certain lofty sort, such as duty, or universal ends. And “instinct” might have its significance so broadened as to cover all impulses whatever, even the impulse to act from the idea of a distant fact, as well as the impulse to act from a present sensation. Were the word instinct used in this broad way, it would of course be impossible to restrict it, as we began by doing, to actions done with no prevision of an end. We must of course avoid a quarrel about words, and the facts of the case are really tolerably plain! Man has a far greater variety of impulses than any lower animal; and any one of these impulses, taken in itself, is as “blind” as the lowest instinct can be; but, owing to man’s memory, power of reflection, and power of inference, they come each one to be felt by him, after he has once yielded to them and experienced their results, in connection with a foresight of those results. In this condition an impulse acted out may be said to be acted out, in part at least, for the sake of its results. It is obvious that every instinctive act, in an animal with memory, must cease to be “blind” after being once repeated, and must be accompanied with foresight of its “end” just so far as that end may have fallen under the animal’s cognizance. An insect that lays her eggs in a place where she never sees them hatch must always do so “blindly;” but a hen who has already hatched a brood can hardly be assumed to sit with perfect “blindness” on her second nest. Some expectation of consequences must in every case like this be aroused; and this expectation, according as it is that of something desired or of something disliked, must necessarily either re-enforce or inhibit the mere impulse. The hen’s idea of the chickens would probably encourage her to sit; a rat’s memory, on the other hand, of a former escape from a trap would neutralize his impulse to take bait from anything that reminded him of that trap. If a boy sees a fat hopping-toad, he probably has incontinently an impulse (especially if with other boys) to smash the creature with a stone, which impulse we may suppose him blindly to obey. But something in the expression of the dying toad’s clasped hands suggests the meanness of the act, or reminds him of sayings he has heard about the sufferings of animals being like his own; so that, when next he is tempted by a toad, an idea arises which, far from spurring him again to the torment, prompts kindly actions, and may even make him the toad’s champion against less reflecting boys.
It is plain then that, no matter how well endowed an animal may originally be in the way of instincts, his resultant actions will be much modified if the instincts combine with experience, if in addition to impulses he have memories, associations, inferences, and expectations, on any considerable scale. An object O, on which he has an instinctive impulse to react in the manner A, would directly provoke him to that reaction. But O has meantime become for him a sign of the nearness of P, on which he has an equally strong impulse to react in the manner B, quite unlike A. So that when he meets O the immediate impulse A and the remote impulse B struggle in his breast for the mastery. The fatality and uniformity said to be characteristic of instinctive actions are so little manifest, that one might be tempted to deny to him altogether the possession of any instinct about the object O. Yet how false this judgment would be! The instinct about O is there; only by the complication of the mental machinery it has come into conflict with another instinct about P.
Here we immediately reap the good fruits of our simple physiological conception of what an instinct is. If it be a mere excito-motor impulse, due to the pre-existence of a certain “reflex-arc” in the nerve-centres of the creature, of course it must follow the law of all such reflex-arcs. One liability of such arcs is to have their activity “inhibited” by other processes going on at the same time. It makes no difference whether the arc be organized at birth, or ripen spontaneously later, or be due to acquired habit, it must take its chances with all the other arcs, and sometimes succeed, and sometimes fail, in draughting off the currents through itself. The mystical view of an instinct would make it invariable. The physiological view would require it to show occasional irregularities
