Assuming then psychism as mode of adaptive reaction, we see the necessity for the correlation of the sense of self with the sense of things. An experiencer blind to self, who has no awareness of self, but merely blindly strives, has little advantage, for it possesses no self-directivity and no power of intelligent action. Its adaptation is purely general; to be specific adaptation it must appreciate differences in environment in their differential action upon itself, an appreciation of the objective in subjective terms. It is probable then that the first knowledge was the apprehension of thing as painer and then of the thing as pleasurer. A discrimination of the two is attained, probably tactile, as hard and soft. The subjective import of the thing is at once realized from these signs.
It is obvious that the origin of self-consciousness must be placed very early in psychic life. With organisms which have but a few flashes of consciousness during their whole individual existence, whose whole experience is a mere sum of separate pleasure-pain thrills and blind efforts, there is neither sense of objectivity nor subjectivity. These very lowest psychisms have experience, but no sense of experience; pleasures and pains possess them, but they do not possess these. But if mentality arises and progresses solely by virtue of its function in saving and profiting the individual living organism, if the end of psychosis is this self-conservation of the bodily whole in its vitality, there is an imperative demand for self-cognizance in order to self-care. Under the law of struggle and survival of the fittest, the organism which does not look out _for itself_ must go to the wall or be in the lowest grade. Self-conservation is closely linked with self-sense. Hence the individual very early acquires some sense of itself in its environment, and so acts and conducts itself. Thus under adverse forces it learns to know itself, to realize its own place and power, and to feel fear, anger, and so to appropriately respond to any environment. Thus is secured manifold and special response to multiform conditions, whereas in the organism which has only pure subjectivity of pain the response would be uniform.