Idealism is to-day the dominant doctrine in philosophy, which was bound to come to it, after a period of raillery, for reasoning leads to it invincibly. We know that there are two idealisms. It is then prudent, whenever this word is employed in a context not purely philosophic, to define it. There are two idealisms, both qualified by a word which is identical in form, but different in meaning, since one comes from _ideal_, the other from _idea_. The former is the expression of a moral or religious state of mind. It is very nearly synonymous with spiritualism, and it is this that M. Brunetière employs when that hard-hearted man becomes sentimental on the subject of the "renaissance of idealism." There is a certain "Revue Idéaliste," marked by a serene religious sentiment, which belongs to the same clan, and in which it would be a mistake to seek any enlightenment on Berkeley's doctrine. The other idealism, which it would have been better to call ideaism, and which Nietzsche has carried to the point of phenomenalism, is a philosophical conception of the world. Schopenhauer, who was not its inventor, has provided it with its best formula--the world is my representation. That is to say, the world is such as it appears to me. If it has a real existence in itself, it is inaccessible to me. It is that which I see it, or feel it, to be. Schopenhauer's formula withstands every criticism. It is irrefutable. The doctrine which derives from it, if attacked directly, presents itself as an impregnable fortress. Every reasoning blunts itself impotently against it. It has this remarkable quality, that it is as valid for the sensation, for the sentiment, as for the idea. There may be based upon it equally, at will, a theory of intelligence, like Taine's, or a theory of sensibility--something which has not been yet attempted. Take the hackneyed statement that the same painful event does not affect with the same intensity two persons whom it strikes with the same external force. That is idealism. Take the subject of tastes and of colours (in which Nietzsche found so much amusement). There too, we have idealism. Whenever we study life, facts, intelligences, physiologies, sensibilities for the purpose of finding, not resemblances, but differences, we are practising idealism. While there is life, there is idealism. That is to say, there are, according to the species, or even the individual, different ways of reacting against an external or internal sensation. Everything is merely representation, for a bird as well as for a man, for a crab as for a cuttle-fish. Reality is relative. A woman, a nervous man even, can suffer intensely--perhaps lose consciousness--by imagining the amputation of a leg, the scraping of the bones. Hardened soldiers, on the contrary, have undergone such operations without flinching. A particular taste for cruelty should not be attributed to the civilizations which countenanced torture, and to those which still practise it.