principle or presumption of science which must be adhered to at any cost, namely:
Nothing could better exhibit Kant's characteristic state of mind on biological questions than this passage. There are occasional bits of sound sense in it and of discriminating judgment about scientific method; and there is a certain power of at least seeing where the significant problems lie. Yet, though he had come under the influence of evolutionistic conceptions, and is in these very writings endeavoring to apply genetic methods to certain biological inquiries, he recoils in horror before the idea of admitting that real species are capable of
- The "Physical Geography" is equally emphatic in repudiating both inheritance of acquired characters and mutation of species: "External things may, indeed, provide the occasions, but they can not be the efficient causes, of the appearance of characters that are necessarily transmitted and inherited. As little as chance or physico-mechanical causes can bring an organic body into existence, just so little can they imprint anything upon the reproductive faculty, that is, produce any effect that is itself reproduced, either as a special form or as a relation of the parts. Air, light and nutrition can modify the growth of an animal body, but they can not furnish this change with a power of reproducing itself after its original causes are no longer operative. . . . For it is not possible that anything should so penetrate into the reproductive faculty as to be capable of gradually removing the creature from its original determination and bringing about a real and self-perpetuating departure from the specific type (Ausartung).