succession.]

The cat runs after the mouse, runs or shows fight before the dog, avoids falling from walls and trees, shuns fire and water, etc., not because he has any notion either of life or death, or of self-preservation. He has probably attained to no one of these conceptions in such a way as to react definitely upon it. He acts in each case separately, and simply because he cannot help it; being so framed that when that particular running thing called a mouse appears in his field of vision he must pursue; that when that particular barking and obstreperous thing called a dog appears there he must retire, if at a distance, and scratch if close by; that he must withdraw his feet from water, and his face from flame.[2]

[Footnote 2: James: Psychology, vol. II, p. 384.]

Similarly, the baby's reaching for random objects, and sucking them when seized, its turning its head aside, when it has had enough food, its crying when alone and hungry, are not, for the most part, deliberate methods invented by the infant to maintain its own welfare, but are almost as automatic as the number of sounds omitted by the cuckoo clock at midnight.

Why do men always lie down, when they can, on soft beds rather than on hard floors? Why do they sit round the stove on a cold day? ... Why does the maiden interest the youth so that everything about her seems more important and significant than anything else in the world? Nothing more can be said than that these are human ways, and that every creature likes its own ways, and takes to the following of them as a matter of course.... Not one man in a billion, when taking his dinner, thinks of utility. He eats because the food tastes good, and makes him want more. If you ask him why he should want to eat more of what tastes like that, instead of revering you as a philosopher, he will probably laugh at you for a fool.[1]

[Footnote 1: James: Psychology, vol. II, p. 386.]

These inborn tendencies to act vary in complexity from the withdrawing of a hand from a hot stove or the jerking of the knee when touched in a particular spot to startlingly involved trains of action to be found in the behavior of certain of the lower animals. Bergson cites the case of a species of wasp which with a skill, unconscious though it be, resembling that of the expert surgeon, paralyzes a caterpillar without killing it, and carries it home for food for its young.[2] There are again many cases of "insects which invariably lay their eggs in the only places where the grubs, when hatched, will find the food they need and can eat, or where the larvæ will be able to attach themselves as parasites to some host in a way that is necessary to their survival."[3] In many instances these complicated trains of action are performed by the animal in a situation absolutely strange to it, without its ever having seen the act performed before, having been born frequently after its parents had died, and itself destined to die long before its grubs will have hatched.

[Footnote 2: Bergson: Creative Evolution, p. 172.]

[Footnote 3: McDougall: Social Psychology, p. 24. (Except where otherwise noted, all references are to the fourth edition.)]

The number and variety of man's instincts. Various attempts have been made, notably by such men as James, McDougall, and Thorndike, to enumerate and classify the tendencies with which man is at birth endowed, or which, like the sex instinct, make their appearance at a certain stage in biological growth, regardless of the particular training to which the individual has been subjected. Earlier classifications were inclined to speak of instincts as very general and as half consciously purposeful in character. Thus it is still popularly customary to speak of the "instinct of self-preservation," the "instinct of hunger," and the "parental instinct." The tendency of present-day psychology is to note just what responses take place in given specific situations. As a result of such observation, particularly by such biologists as Watson and Jennings,[1] instincts have come to be regarded not as general and purposive but as specific and automatic. Thus it is no instinct of self-preservation that drives the child to blink its eyes at a blinding flash of light; it is solely and simply the very direct and immediate tendency to blink its eyes in just that way whenever such a phenomenon occurs. It is no deliberate intent to inhale the oxygen necessary to the sustenance of life that causes us to breathe. No more is it a conscious plan to provide the organism with nourishment that prompts us to eat our breakfast in the morning; it is simply the immediate and irresistible enticement of food after a night's fast. Not a deliberate motive of maternity prompts the mother to caress and care for her baby, but an inevitable and almost invincible tendency to "cuddle it when it cries, smile when it smiles, fondle it and coo to it in turn."

[Footnote 1: Watson: Behavior. H. S. Jennings: Behavior of the Lower Organisms.]

In the last few years, as a result of the observation of animals under laboratory conditions, there has been increasing evidence of a large number of specific tendencies to act in specific ways, in response to specific given stimuli. As no stimuli are ever quite alike, and no animal organism is ever in exactly the same physico-chemical condition at two different times, there are slight but negligible differences in response. Allowing for these, animals may be said to be equipped with a wide variety of tendencies to do precisely the same things under recurrent identical circumstances. The aim of the experimental psychologist is to discover just what actions occur when an animal is placed in any given circumstances, precisely as the chemist notes what reaction occurs when two chemicals are combined.

While experiments with the human infant are more difficult and rare (and while it is among infants alone among humans that original tendencies can be observed free from the modifications to which they are so soon subjected by training and environment) careful observers find in the human animal also a great number of these specific ways of acting. Just which of the large number of observed universal modes of behavior are original and unlearned, is a matter still in controversy among psychologists. There is practically complete agreement among them, however, with respect to such comparatively simple acts as grasping, reaching, putting things in the mouth, creeping, standing and walking, and the making of sounds more or less articulate. Most psychologists recognize even such highly complicated tendencies as man's restlessness in the absence of other people, his tendency to attract their attention when present, to be at once pitying and pugnacious, greedy and sympathetic, to take and to follow a lead.

In general, it may be said that man possesses not fewer instincts than animals, but more. His superiority consists in the fact that he has at once more tendencies to respond, and that in him these tendencies are more flexible and more susceptible of modification than those of animals. A chicken has at the start the advantage over the human; it can at first do more things and do them better. But it is the human baby who, though it cannot find food for itself at the start, can eventually be taught to distinguish between the nutritive values of food, secure food from remote sources, and make palatable food from materials which when raw are inedible.

An inventory and classification of man's original tendencies