by means of that essay what the principle of sufficient reason is and signifies, what its validity extends to, and what it does not extend to, and that that principle is not before all things, and the whole world merely in consequence of it, and in conformity to it, a corollary, as it were, of it; but rather that it is merely the form in which the object, of whatever kind it may be, which is always conditioned by the subject, is invariably known so far as the subject is a knowing individual: only then will it be possible to enter into the method of philosophy which is here attempted for the first time, and which is completely different from all previous methods.
But the same disinclination to repeat myself word for word, or to say the same thing a second time in other and worse words, after I have deprived myself of the better, has occasioned another defect in the first book of this work. For I have omitted all that is said in the first chapter of my essay “On Sight and Colour,” which would otherwise have found its place here, word for word. Therefore the knowledge of this short, earlier work is also presupposed.
Finally, the third demand I have to make on the reader might indeed be tacitly assumed, for it is nothing but an acquaintance with the most important phenomenon that has appeared in philosophy for two thousand years, and that lies so near us: I mean the principal writings of Kant. It seems to me, in fact, as indeed has already been said by others, that the effect these writings produce in the mind to which they truly speak is very like that of the operation for cataract on a blind man: and if we wish to pursue the simile further, the aim of my own work may be described by saying that I have sought to put into the hands of those upon whom that operation
