As we ourselves feel absolutely incapable of adding anything specific to the general statement that there *must* be an unknown principle of transformism, if the hypothesis of descent is justified at all, we may here close our discussion of the subject. 5. THE LOGICAL VALUE OF THE ORGANIC FORM ACCORDING TO THE DIFFERENT TRANSFORMISTIC THEORIES A few words only must be added about two topics: on the character of organic forms as regarded by the different transformistic theories, and on the relation of transformism in general to our concept of entelechy. We have learnt that both Darwinism and Lamarckism, in their dogmatic shape, regard the specific forms of animals and plants as being contingent; in fact, it was to this contingency that criticism was mainly directed. We therefore are entitled to say that to Darwinism and Lamarckism organic forms are accidental in the very sense of the *forma accidentalis* of the old logicians. There are indefinite forms possible, according to these theories, and there is no law relating to these forms. Systematics, under such a view, must lose, of course, any really fundamental importance. “There is no rational system about organisms”: that is the ultimate statement of Darwinism and of Lamarckism on this doubtful question. Systematics is a mere catalogue, not at present only, but for ever, by the very nature of the organisms. It is not owing to the indefinite number of possible forms that both our theories came to deny the importance of systematics, but to the want of a *law* relating to this indefinite number: among chemical compounds indefinite possibilities also exist in some cases, but they obey the law of the general formula. It is very strange that Darwinians of all people are in the forefront of systematic research in all countries: do they not see that what they are trying to build up can only relate to accidental phenomena? Or have they some doubts about the foundations of their own theoretical views, in spite of the dogmatic air with which they defend them? Or is it the so-called historical interest which attracts them? A new question seems to arise at this point: Have not we ourselves neglected history in favour of systematics and laws? Our next lecture, the last of this year, will give the answer to this question. At present we continue our study of the possible aspects of systematics. It is not difficult to find out what meaning organic forms would assume under any phylogenetic theory opposed to the theories of contingency. It was their defence of contingency, that is, their lack of any law of forms, that caused these theories to be overthrown--reduced to absurdities even--and therefore, it follows that to assume any kind of transformistic law is at the same time to deny the accidental character of the forms of living beings.