At this point there is a natural transition to logic. A creature like woman, the absolute woman, who is not conscious of her own identity at different stages of her life, has no evidence of the identity of the subject-matter of thought at different times. If in her mind the two stages of a change cannot be present simultaneously by means of memory, it is impossible for her to make the comparison and note the change. A being whose memory is never sufficiently good as to make it psychologically possible to perceive identity through the lapse of time, so as to enable her, for instance, to pursue a quantity through a long mathematical reckoning; such a creature in the extreme case would be unable to control her memory for even the moment of time required to say that A will be still A in the next moment, to pronounce judgment on the identity A = A, or on the opposite proposition that A is not equal to A, for that proposition also requires a continuous memory of A to make the comparison possible.
I have been making no mere joke, no facetious sophism or paradoxical proposition. I assert that the judgment of identity depends on conceptions, never on mere perceptions and complexes of perceptions, and the conceptions, as logical conceptions, are independent of time, retaining their constancy, whether I, as a psychological entity, think them constant or not. But man never has a conception in the purely logical form, for he is a psychological being, affected by the condition of sensations; he is able only to form a general idea (a typical, connotative, representative conception) out of his individual experiences by a reciprocal effacing of the differences and strengthening of the similarities, thus, however, very closely approximating to an abstract conception, and in a most wonderful fashion using it as such. He must also be able to preserve this idea which he thinks clear, although in reality it is confused, and it is memory alone that brings about the possibility of that. Were he deprived of memory he would lose the possibility of thinking logically, for this possibility is incarnated, so to speak, only in a psychological medium.
