I, on the contrary, maintain that we are never entitled to raise into a _genus_ that which we only know of in a single species. For we could bring nothing into our idea of the _genus_ but what we had abstracted from this one species; so that what we should predicate of the _genus_ could after all only be understood of the single species. While, if we should attempt to think away (without any warrant) the particular attributes of the species, in order to form our _genus_, we should perhaps remove the exact condition whereby the remaining attributes, hypostatised as a _genus_, are made possible. Just as we recognise =intelligence in general= to be an attribute of animal beings alone, and are therefore never justified in thinking of it as existing outside, and independent, of animal nature; so we recognise =Reason= as the exclusive attribute of the human race, and have not the smallest right to suppose that Reason exists externally to it, and then proceed to set up a _genus_ called "Rational Beings," differing from its single known species "Man"; still less are we warranted in laying down laws for such imaginary =rational beings in the abstract=. To talk of rational beings external to men is like talking of =heavy beings= external to bodies. One cannot help suspecting that Kant was thinking a little of the dear cherubim, or at any rate counted on their presence in the conviction of the reader. In any case this doctrine contains a tacit assumption of an _anima rationalis,_ which as being entirely different from the _anima sensitiva_, and the _anima vegetativa_, is supposed to persist after death, and then to be indeed nothing else but _rationalis_. But in the _Kritik der Reinen Vernunft_ Kant himself has expressly and elaborately made an end of this most transcendent hypostasis. Nevertheless, in his ethics generally, and in the _Kritik der Praktischen Vernunft_ especially, there seems always to hover in the background the thought that the inner and eternal essence, of man consists of =Reason=. In this connection, where the matter only occurs incidentally, I must content myself with simply asserting the contrary. Reason, as indeed the intellectual faculty as a whole, is secondary, is an attribute of phaenomena, being in point of fact conditioned by the organism; whereas it is the =Will= in man which is his very self, the only part of him which is metaphysical, and therefore indestructible.