By the evolution of anger then, as in contradistinction to fear, two grand divisions of animate existence were set apart, two great psychical orders as fundamentally distinct and important for evolutionary psychics, as invertebrate and vertebrate for biology. The rise of the back-boned animal is not more important for physiological morphology than the evolution of anger for psychical morphology, and, indeed, as we have before remarked, the psychical growth is ever the broadest and deepest fact in evolution. By the acquirement and predominance of the anger stimulus certain animals became differentiated as a distinct class from their fearful neighbours, and they then by this new impulse gradually attained instruments of offence, and also by increase of size became physically distinct forms. Henceforth the animate world becomes divided in a more and more marked way into pursuers and pursued. By mutual interaction fear is increased on one side as anger increases on the other, and the division into timid and fierce, predacious and prey, becomes more and more established and marked.

We take it then that it was a most momentous day in the progress of mind when anger was first achieved, and some individual actually got mad. If the exact date and the particular individual were ascertainable a memorial day set apart for all time would not be too great an honour. In the struggle of existence, other things being equal, the most irascible is the most successful, faring the best, securing the best mate, and having the best and most numerous progeny. Susceptibility to anger becomes a necessity to a large class of organisms, and those who will not get angry and fight for their interests are surely trampled on or pushed aside to become starveling or outcast.

Is now this primitive anger an absolutely new power, a de novo evolution, or is it possible to study its rise as a gradual differentiation from some other factor? Must we not view psychical evolution like all evolution as coming under the law of continuity? How then explain the sudden rise of apparently new and distinct forms like anger or fear? Anger as a response to the demands of life seems from the very first to be as distinctly and peculiarly anger as at any time in its development. The peculiar quality which makes anger anger, does not seem to appear as a gradual differentiation from other elements as slowly emerging from previous modes, but we can only judge that it bursts suddenly upon the field as a new and unique creation, which does not find its explanation in pre-existent forms and cannot be traced as a gradual evolution from them. On the other hand, while it does not at first sight seem possible to regard anger as being from the first other than a radically new power and activity determined, indeed, by the struggle for existence, but wholly unexplained in its essence and formation as a consciousness related to and differentiated from other consciousnesses, yet we must acknowledge our profound ignorance of the real morphology of mind and what is the real nature of mental differentiation. Here the problem is altogether more difficult than in biology, where the appearance of new forms like wings can be readily traced as slow modifications of previous members, the physical possibility and rationale of which is easily seen to be inherent in the physical constitution of the body and its circumambient matter, the air. However, in the present state of our psychical knowledge it is quite impossible to attain any similarly clear conception as to the formation of new psychical forms. We may see why they should be called into being by the necessities of animate life, we can perceive their functional importance from the first, but to trace their morphological development as gradually assuming their peculiar qualities as modifications of already existing activities, and as inherently possible in the psychical constitution of things, this is clearly beyond us at present. We can conceive that the earliest anger was weak and rather ineffective as compared with the fully developed anger of later life, but we cannot see that it was any the less anger, any the less purely and wholly sui generis than the very latest and strongest form. Has it ever in its earlier stages that hybrid and mixed character which marks it as a modification of existent factors? It is certainly not a modified fear, to which it is, indeed, a polar opposite.

But we may perhaps regard anger, and fear as well, as modified from previous general emotion. We may, indeed, consider it likely that some general emotional phase preceded the special emotions, just as a general indefinite pain and pleasure preceded definite pains and pleasures. It may be considered as probable that emotion first appeared as a purely undifferentiated disturbance sequent on sense of the experienceable pain, this general emotion being neither fear nor anger, but the basis from which both develop. The psychic agitation we term emotional very likely began in a purely general form, yet it is hard to understand how peculiar forms develop therefrom. We are too far from such inchoate experience to readily come to any appreciation of its method or mode. We may be disturbed as to something imminent and know not whether to fear or be angry, but this in general means only a rapid alternation of fear and anger according as the mind runs back and forth between fear and anger-provoking elements. It is unlikely that we can trace in any such a purely undifferentiated emotion.

At the best we but throw the difficulty farther back, for emotion per se is then the de novo form to which the principle of continuity does not seem to apply. If anger is a traceable modification of some more general emotion as combined with definite representation and volition modes, yet how the peculiar anger quality is achieved is still unexplained. On the whole it seems simplest and truest to assume the first impulse of anger as a perfectly new and diverse wave of emotion suddenly generated in answer to some extreme urgency in the struggle of existence.

The analogy of organic and psychic evolution may be pressed to a certain extent. It is plainly possible to set in order an evolutionary series of light—sensing organs, eyes—from most elementary to most complex, and it is quite as possible, though yet to be done, to set forth in similar genetic order a series of psychic states as offence-sense, i.e., angers, in their increasing differentiation. But previous to any eye, to local visualization, there is a period of common sensation when an absolutely simple organism is in every part equally responsive to light; in a crude way the whole organism reacts to light, from which stage by traceable specialization the eye as a light-sensing organ is gradually developed. Here analogy would seem to fail, unless we consider it to be the stage when any psychosis, e.g., anger, requires the whole consciousness capacity, mind being merely a capacity for the recurrent but isolated single-activities. Mind certainly but slowly grows into that sum of organic coincident interdependent yet distinct consciousnesses which we commonly think of under the term, mind. Anger in its very earliest and lowest form is no doubt an absorbing naïve isolated wave, as common to mind as a whole, that is, as making up the whole of mind for the time being, is perhaps in its measure an analogy to common sensation. Anger may then be but a common emotion, answering in a certain aspect to light-sense, sound-sense, etc., as purely common sensations. But we must remark that general sensation is not to be confounded with common sensation, or general emotion with common emotion. Common sensations are, indeed, usually very general in form, and a sensation per se, a purely general sensation, is probably very rarely anything else, yet when we close the eyes and direct them toward the sun, the general sensation of light we receive—very like the original primitive common sensation—is general, yet by a special organ. The word common refers, not to the special nature of the function itself, but the fact that the function, whether special or general, is performed indifferently, or practically so, by the common whole. A sensation of coloured light is more special than a mere sensation of light, and this than mere general sensation of force, but all may be accomplished either by common sensation or special sensation. General emotion may similarly be either common or in organic co-activity. There was certainly a time when consciousness existed which was not and could not be anger or fear or even an emotion per se. Pre-emotional and pre-representative consciousness was so absolutely primitive, general, and common, that psychology as a necessarily automorphic science will be very long in coming to any understanding of this field, but yet we must set it off as something which must always receive some consideration. Anger is not a property of all consciousness by the nature of consciousness itself, but is merely a possible mode dependent on circumstances for its development at a certain psychic stage.

What now is the inner nature and what the constituent elements of the anger state? Comparatively few reflect upon their emotions save from an ethical standpoint, and very few indeed attempt any analysis of them. To determine the process and exact psychical constituents of getting mad and being mad, may seem to many a quite useless and foolish introspective endeavour. If a person is angry, he is angry, and that is all there is of it, will be the general verdict of common sense. You can dissect flowers into their parts, you can analyse rocks and soils, but any emotion such as anger is wholly unanalyzable. No one can know what it is to be mad until he has once been mad, and, thereafter, he can only reflect upon it as a peculiar excitement, a powerful agitation, whose occasions and results may be fully traced, but which in itself is sui generis and irresolvable. The form of consciousness we know as being angry, is really a simple wave of emotion which stands by itself as an elementary and ultimate form.

Suppose we acknowledge these remarks as true, we may yet maintain that anger, like all emotions, is a highly complex state of manifold factors whose sum total, whose grand resultant, is a seemingly simple and peculiar status. Why should one arrangement of atoms produce a peculiar perfume, another a peculiar stench? Anger may likewise be merely an unexplainable ensemble of early ascertainable elements.

Certain it is, in the first place, that sense of object is necessary to anger. One cannot be mad without being mad at something. The attitude of mind is objective, and even rage in its blindest moment preserves this attitude. Blind with rage, means no more than that various definite qualities of the object are lost in the intense emotional reaction at pain-giver. At its height, anger preserves, indeed, only the barest apprehension of object; but this is intense and overpowering in connection with the sense of it as infringing and injuring. In the transports of rage and fury, the movements are wild and reckless enough, but always antagonistic, implying outward destructive activity. Anger is the fixation of the mind upon some object in its quality of personal hurtfulness, and is revulsion, not from it, as fear, but against it. With early psychisms, all perceptions of objects end in either anger or fear, and a large part of early education consists in learning what objects to be fearful of, and what to be angry at. The alertness of wild animals is determined mainly by either nascent fear or anger. When a dog is suddenly wakened from sleep he generally shows either fear or anger. This is merely an illustration of how the dimmest sense of object immediately connects itself with emotion as primitive and fundamental tendency. The organism perceives the object, and representing its imminent hurtfulness, feels fear and dashes away from it, or feels anger and dashes against it. These are the two simplest possible reactions with sense of the experienceable injurious. In fear there is elimination of oneself from the injury, and in anger the elimination of the injury from oneself. With later anger and fear these processes of elimination themselves become matters of representation, and make a large part in highly-developed forms.

A knowledge which very generally enters into anger is the comparative estimate of power. A cat scratches us, we are angry; a lion threatens us, we are afraid. The progress of the lower psychic life is largely in learning what is best to fear and what should excite anger. That which at first angers will often, when better understood, produce fear, and vice versâ. Wild animals at first often show merely anger when molested by man, but soon manifest fear as they learn to appreciate his superior power. The African elephant learns to distinguish between the savage with his spear, and the white hunter with his rifle, and is merely irritated or angry with the one, while he manifests genuine fear of the other. The young of animals and of man continually show irrelevant fear and anger. They are generally either over fearful or over irritable. Our own feelings are powerfully modified by varying estimates of opposing force and injury. If, in passing through a dark street, I am tripped by what I take to be a child’s snare, I am angered, but upon noticing that it is a fuse to a dynamite bomb, I am thrown into intense fear. In general, any sensation, as of sound or light, in its lower grades of intensity produces anger, in higher occasions fear. As a rule when reactions induced by either fear or anger are uniformly unsuccessful, natural selection favours the development of the other.