“instinct,” however, _is_ to provide for a more or less distant future, often, as we have seen, the future of another generation. It is essentially _telic_, and directed to a future unforeseen, but generally useful, end. This explanation, then, is fundamentally and necessarily inadequate. It is like an explanation of the building of a house, by “bricks, mortar, bricklayers, and hodmen,” with the omission of all reference to any influence governing their motions and directing them towards a common and predetermined end which is not theirs. But though we cannot _explain_ “instinct” by “reflex action,” there is none the less a certain obvious affinity between these two forms of animal activity, and it is in part my object to point out the nature of this very affinity. Next we may pass in review the two hypotheses that instinct is but (1) a form of intelligence, or (2) individual experience. As to the first, I have already given instances of unquestionably instinctive actions performed by birds as soon as they quit the eggshell, and it would be but waste of time to argue against the view that the human infant is guided by intelligent purpose and conscious foresight in his very first acts of sucking, swallowing, and defecation. Actual intelligence, therefore, is a radically insufficient explanation, as also, for the very same reasons, is Condillac’s hypothesis as to individual experience. About “lapsed intelligence” I will speak later on. Lemarck’s hypothesis, that instinct is but inherited habit, is one which is much more worthy of careful consideration than any we have yet considered. For it may be admitted at once that habits may be inherited. There are many instances of such inheritance in human beings, and as regards the lower animals, the barking of dogs may be taken as an instance of a habit thus perpetuated. In fact “habit,” when inherited, so simulates instinct, that their confusion is far from surprising. There is, however, this radical difference between them: “habit” enables an agent to repeat with facility and precision an act which has been done before, but “instinct” determines with precision the first performance of such act. Referring instinct to habit, but temporarily relieves the difficulty of those who object to instinct, by putting it a step back. It is impossible to believe that any of the progenitors of an infant of to-day first acquired, during his or her lifetime, the habit of sucking, or that the habits of neuter insects thus arose. But after all, if we _could_ explain “instinct” by “habit,” should we thereby make the phenomena less mysterious? “Habit” is due to an internal spontaneity of living things. A living thing no doubt requires some internal solicitation, in order that it should move, but when it does move that movement is _its own_. All living organisms tend to act. With them action is not only their nature, ’tis a want; and, within limits, their powers and energies increase with action, and