For the others (whose opinion I adopt), the whole may be explained on physico-chemical grounds. No doubt there is affinity, attraction and repulsion, but only in the scientific sense; these words are metaphors derived from the language of consciousness which should be purged of all anthropomorphic elements. Several authors have shown by numerous observations and experiments the chemical conditions which determine or prevent this pretended choice (Sachs, Verworn, Löb, Maupas, Bastian, etc.). On this point, as on all questions of origin, we must decide according to probabilities, and the probabilities appear to be all in favour of the chemical hypothesis. In any case, this matter has only a secondary interest for us here. If we admit conscious tendencies, then the origin of the emotional life coincides with the very origin of physiological life. If we eliminate all psychology, there still remains the physiological tendency, that is to say the motor element, which in some degree, from the lowest to the highest, is never quite wanting. This excursion into the pre-conscious period—since we so regard it—puts us in possession of one result. At the end of this investigation we find two well-defined tendencies, physico-chemical and organic—the one of attraction, the other of repulsion; these are the two poles of the life of feeling. What is attraction in this sense? Simply assimilation; it blends with nutrition. With sexual attraction, however, we must note that we already reach a higher grade; the phenomenon is more complex, the monocellular being no longer acts to preserve itself but to maintain the species. As to repulsion, we may remark that it is manifested in two ways. On one side it is the opposite of assimilation: the cell or the tissue rejects what does not suit it. On another side, at a somewhat superior stage, it is in some degree already defensive. We have thus gained a basis for our subject by finding that beneath the conscious life of feeling there exists a very low and obscure region, that of vital or organic sensibility, which is an embryonic form of conscious sensibility and supports it. II.