It is important to notice that this *causa vera* would imply vitalistic causality when taken in the wide meaning which Lamarckism allows to it: indeed, the power of active adaptation to indefinite changes would imply a sort of causal connection that is nowhere known except in the organism. Lamarck himself is not very clear about this point, he seems to be afraid of certain types of uncritical vitalism in vogue in his days; but modern writers have most clearly seen what the logical assumptions of pure Lamarckism are. Next to Cope, August Pauly[146] may be said to be the most conscious representative of a sort of so-called psychological vitalism, which indeed Lamarckism as a general and all-embracing theory must have as its basis. [146] *Darwinismus und Lamarckismus*, München, 1905. THE ACTIVE STORING OF CONTINGENT VARIATIONS AS A HYPOTHETIC PRINCIPLE This point will come out more fully, if now we turn to study a certain group of principles, upon which dogmatic Lamarckism rests: I say principles and not facts, for there are no facts but only hypothetic assumptions in this group of statements. We do know a little about adaptations, at least to a certain extent, and it was only about the sphere of the validity of a law, which was known to be at work in certain cases, that hypothetical additions were made. In the second group of the foundations of Lamarckism we know absolutely nothing; accidental variations of form are supposed to occur, and the organism is said to possess the faculty of keeping and storing these variations and of handing them down to the next generation, if they happen to satisfy any of its needs. But these needs are not of the actual type, brought forth by a change of the functional state of the individual, as in the case of adaptations: they are of a somewhat mysterious nature. A glance at the theory of the origin of the movements which are called acts of volition in the human child may serve to elucidate what is meant.