with his inveterate hostility to the hypothesis of the luminiferous ether, which certainly gratifies our "predilection for order and harmony," not to say our "besoin d'idealite", in no ordinary degree. This notion of the "destination" of the study of natural laws is to our minds a complete dereliction of the essential principles which form the Positive conception of science; and contained the germ of the perversion of his own philosophy which marked his later years. It might be interesting, but scarcely worth while, to attempt to penetrate to the just thought which misled M. Comte, for there is almost always a grain of truth in the errors of an original and powerful mind. There is another grave aberration in M. Comte's view of the method of positive science, which though not more unphilosophical than the last mentioned, is of greater practical importance. He rejects totally, as an invalid process, psychological observation properly so called, or in other words, internal consciousness, at least as regards our intellectual operations. He gives no place in his series of the science of Psychology, and always speaks of it with contempt. The study of mental phaenomena, or, as he expresses it, of moral and intellectual functions, has a place in his scheme, under the head of Biology, but only as a branch of physiology. Our knowledge of the human mind must, he thinks, be acquired by observing other people. How we are to observe other people's mental operations, or how interpret the signs of them without having learnt what the signs mean by knowledge of ourselves, he does not state. But it is clear to him that we can learn very little about the feelings, and nothing at all about the intellect, by self-observation. Our intelligence can observe all other things, but not itself: we cannot observe ourselves observing, or observe ourselves reasoning: and if we could, attention to this reflex operation would annihilate its object, by stopping the process observed.