Schopenhauer's theory of knowledge is given in the essay by which he obtained his doctor's degree, _On the Four-fold Root of the Sufficient Reason_. Notwithstanding this rather alarming title, it is a singularly clear and readable work. The standpoint is a simplification of Kant's _Critique_. The objects of consciousness offer themselves to the thinking, acting subject as grouped presentations in which there is "nothing sudden, nothing single." (1) When a new object appears to us, it must have a cause, physical, physiological, or psychological; and this we call the reason why it becomes. (2) Objects are referred to concepts of more or less generality, according to the logical rules of definition, classification, and inference; that is the reason of their being known. (3) Objects are mathematically determined by their position relatively to {121} other objects in space and time; that is the reason of their being. (4) Practical objects or ends of action are determined by motives; the motive is the reason why one thing rather than another is done. The last "sufficient reason" takes us to ethics. Schopenhauer agrees with Kant in holding that actions considered as phenomena are strictly determined by motives, so much so that a complete knowledge of a man's character and environment would enable us to predict his whole course of conduct through life. Nevertheless, each man, as a timeless subject, is and knows himself to be free. To reconcile these apparently conflicting positions we must accept Plato's theory that each individual's whole fate has been determined by an ante-natal or transcendental choice for which he always continues responsible. Nevertheless, cases of religious "conversion" and the like prove that the eternal reality of the Will occasionally asserts itself in radical transformations of character and conduct. In ethics Schopenhauer distinguishes between two ideals which may be called "relative" and "absolute" good. Relative good agrees with the standard of what in England is known as Universalistic Hedonism--the greatest pleasure combined with the least pain for all sensitive beings, each agent counting for no more than one. Personally passionate, selfish, and brutal, Schopenhauer still had a righteous abhorrence of cruelty to animals; whereas Kant had no such feeling. But positive happiness is a delusion, and no humanity can appreciably diminish the amount of pain produced by vital competition--recognised by our philosopher before Darwin--in the world. Therefore Buddhism is right, and the higher morality bids us extirpate the {122} will-to-live altogether by ascetic practices and meditation on the universal vanity of things. Suicide is not allowed, for while annihilating the intelligence it would not exclude some fresh incarnation of the will. And the last dying wish of Schopenhauer was that the end of this life might be the end of all living for him. HERBART.