In order to combat Condillac, Helvetius and the ideologists, Gall takes his stand upon experience, that is to say upon mental physiology and pathology, and also upon the observation of animals. As a fact, each individual comes into the world with tendencies, with predispositions, with innate faculties. The supposed natural equality of all men is an ill-founded abstraction, since their propensities and their qualities often differ very greatly. The paradox of Helvetius who attributes the moral and intellectual inequality of men to the all powerful influence of education and of circumstances, cannot be upheld. We cannot, as we will, make just minds and upright souls. Variety of organs entails diversity of functions; the difference between men and animals, as that of men among themselves, is therefore due to anatomical and and physiological differences. Condillac’s absolute sensualism is thus refuted by facts. Moreover, if the science of psychology does not advance it is because distinctions between the faculties of the soul, (memory, imagination, judgment, etc.) have been arbitrarily established, from a metaphysical and logical point of view, which does not correspond to the real speciality of the functions. Gall lays down the following principle as the ultimate conclusion of experience, and the fundamental basis of his doctrine of the functions of the brain:[188] _The dispositions of the individual soul and mind are innate and their manifestation depends upon the organisation_. We must not see in this a return to the _a priori_ method. Gall guards against reverting to the innateness of Descartes and Leibnitz. He means to speak simply of dispositions, or tendencies, or “faculties,” for instance, the faculty of love, the feeling of the just and of the unjust, ambition, the faculty of learning languages, that of comparing several judgments or ideas, of deducing consequences from them, etc. “We confine ourselves,” says Gall, “to observation.” We only consider the faculties of the soul in so far as they become phenomena for us by means of the material organs. We deny and affirm nothing except that which can be brought under judgment by experience. Comte assents to all this. With Gall he condemns the “childish dreams” of Condillac and of his successors about transformed sensations[189]; with him he admits the speciality of the psychical functions, corresponding to the speciality of the cerebral organs. But he only borrows Gall’s principle. He has the strongest objections even to Gall’s psychology. Undoubtedly at the time when Gall lived, no one could have done better, and his effort deserves to be admired. But his errors, although they were inevitable, are errors none the less.