The foregoing analysis of human behavior might thus be briefly summarized. We found that man is born a creature with certain tendencies to act in certain definite ways, tendencies which he largely possesses in common with the lower animals. We found also that man could learn by trial and error, that his original instinctive equipment could be modified. Thus far in his mental life man is indistinguishable from the beasts. But man’s peculiar capacity, it appeared, lay in his ability to think, to control his actions in the light of a future, to choose one response rather than another because of its consequences, which he could foresee and prefer. This capacity for reflection, for formulating a purpose and being able to obtain it, we found to be practical in its origins, but persisting on its own account in the disinterested inquiry of philosophy and science and the free imaginative construction of art. And in all man’s behavior, whether on the plane of instinct, habit, or reflection, we found action to be accompanied by emotion, by love and hate, anger and awe, which might at once impede action by confusing it, or sustain it by giving it a vivid and compelling motive.

The second part of the book was devoted to an analysis of the various specific traits which human beings display and the consequences that these have in men’s relations with one another. Under certain conditions, one or another of these may become predominant; in particular historical conditions, one or another of them may have a high social value or the reverse. These traits vary in different individuals; in any of them, a man may be totally defective or abnormally developed. But taken in general, they constitute the changeless pattern of human nature, and fix the conditions and the limits of action.

But while these universal traits determine what man may do, and fix definitively the boundaries of human possibility, within these limits the race has a wide choice of ideals and attainments. The standards of what man will and should do, within the boundaries of the nature which is his inheritance, are to be found not in his original impulses, but in his mind and imagination. The human being is gifted with the ability to imagine a future more desirable than the present, and to contrive ingeniously in behalf of anticipated or imagined goods.

These anticipated goods we call ideals, and these ideals arise, in the last analysis, out of the initial and inborn hungers and cravings of men. “Intellect is of the same flesh and blood with all the instincts, a brother whose superiority lies in his power to appreciate, harmonize, and save them all.” The function of reason is not to set itself over against men’s original desires, but to envisage ideals and devise instruments whereby they may all, so far as nature allows, be fulfilled.

Man’s reason, then, which has its roots in his instincts, is the means of their harmonious fulfillment. It attempts, in the various fields of experience, to effect an adjustment between man’s competing desires, and between man and his environment. If instincts were left each to its own free course, they would all be frustrated; if man did not learn reflectively to control his environment, and to make it subserve his own ends, he would be a helpless pygmy soon obliterated by the incomparably more powerful forces of Nature.

These various attempts of man to effect an adjustment of his passions with one another, and his life to his environment, may be described as the “Career of Reason.” In this career man has formulated many ideals, not a small number of which have led him into error, disillusion, and unhappiness. Sometimes they have misled him by promising him fulfillments that were in the nature of things unattainable. They have added to the real evils of life a longing after impossible goods, goods which an informed intelligence would early have dismissed as unattainable. Man has disappointed himself by counting on joys which, had he been less incorrigibly addicted to imaginative illusions, he should never have expected. Sometimes he has framed ideals which could be fulfilled, but only at the expense of a large proportion of natural and irrepressible human desires. Such, for example, have been the one-sided ascetic ideals of Stoicism or Puritanism, which in their attempt to give order and form to life, crush and distort a considerable portion of it. The same is true of mysticism which seeks frequently to attain life by altogether denying its instinctive animal basis. Yet though reason has led men astray, it is the only and ultimate hope of man’s happiness. It is responsible for whatever success man has had in mastering the turmoil of his own passions and the obstacles of an environment “which was not made for him but in which he grew.” It has given point and justice to Swinburne’s exultant boast:

“Glory to man in the highest! For man is the master of things!”

This Career of Reason has taken various parallel fulfillments, and in each of them man has in varying degrees attained mastery. Religion arose as one of the earliest ways by which man attempted to win for himself a secure place in the cosmic order. Science, in its earliest forms hardly distinguishable from religion, is man’s persistent attempt to discover the nature of things, and to exploit that discovery for his own good. Art is again an instance of man’s march toward mastery. Beginning, in the broadest sense, in the industrial arts, in agriculture and handicrafts, it passes, as it were by accident, from the necessary to the beautiful. Having in his needful business fortuitously created beautiful objects, man comes to create them intentionally, both for their own sake and for the sheer pleasure of creation.

Finally in morals men have endeavored to construct for themselves codes of conduct, ideals of life, in which no possible good should be needlessly or recklessly sacrificed, and in which men might live together as happily as is permitted by the nature which is at once their life and their habitation. The Career of Reason in these various fields we shall briefly trace and describe. We must expect to find, as in any career, however successful, failures along with the triumphs, and, as in any notable career still unfinished, possibility and great promise. Man’s reason and imagination have a long past; they have also an indefinite future. Man has in the name of reason made many errors; but to reason he owes his chief success, and with increasing experience he may be expected to attain continually to a more certain and effective wisdom. With these provisos, let us address ourselves to the Career of Reason, beginning with religion.