There is no *forma accidentalis*. Does that mean that the *forma essentialis* is introduced by this mere statement? And what would *that* assert about the character of systematics? THE ORGANIC FORM AND ENTELECHY This problem is not as simple as it might seem to be at the first glance, and, in fact, it is insoluble at present. It is here that the relation of the hypothetic transformistic principle to our concept of entelechy is concerned. We know that entelechy, though not material in itself, uses material means in each individual morphogenesis, handed down by the material continuity in inheritance. What then undergoes change in phylogeny, the means or the entelechy? And what would be the logical aspect of systematics in either case? Of course there would be a law in systematics in any case; and therefore systematics in any case would be rational in principle. But if the transformistic factor were connected with the means of morphogenesis, one could hardly say that specific form as such was a primary essence. Entelechy would be that essence, but entelechy in its generality and always remaining the same in its most intimate character, as the specific diversities would only be due to a something, which is not form, but simply means to form. But the *harmony* revealed to us in every typical morphogenesis, be it normal or be it regulatory, seems to forbid us to connect transformism with the means of morphogenesis. And therefore we shall close this discussion about the most problematic phenomena of biology with the declaration, that we regard it as more congruent to the general aspect of life to correlate the unknown principle concerned in descent with entelechy itself, and not with its means. Systematics of organisms therefore would be in fact systematics of entelechies, and therefore organic forms would be *formae essentiales*, entelechy being the very essence of form in its specificity. Of course systematics would then be able to assume a truly rational character at some future date: there might one day be found a principle to account for the totality of possible[160] forms, a principle based upon the analysis of entelechy.[161] As we have allowed that Lamarckism hypothetically explains congenital adaptedness in histology, and that Darwinism explains a few differences in quantity, and as such properties, of course, would both be of a contingent character, it follows that our future rational system would be combined with certain accidental diversities. And so it might be said to be one of the principal tasks of systematic biological science in the future to discover the really rational system among a given totality of diversities which cannot appear rational at the first glance, one sort of differences, so to speak, being superimposed upon the other. [160] The word “possible” relating to originating, of course, not to surviving. It is here that natural selection may acquire its logical importance alluded to above (see page 264).