Although people cannot define existence and do use the term with some looseness, yet it is possible to give an extensive definition by pointing to th… - C. D. Broad

There is no important problem in any branch of philosophy which is not treated by Kant, and he never treated a problem without saying something illuminating and original about it. He was certainly wrong on many points of detail, and he may well be wrong in his fundamental principles; but, when all criticisms have been made, it seems to me that Kant’s failures are more important than most men’s successes.

There certainly are changes of fashion in philosophy. When a new kind is in vogue, many things in the philosophy of an earlier day, which are of permanent value and perhaps highly relevant to contemporary problems, tend to be altogether forgotten or carelessly and ignorantly dismissed, simply because they occur in an out-of-date setting and are clad in an unfashionable dress. It is now quite certain that much of permanent value in Scholastic philosophy was ignored or contemned from this cause by Locke, Berkeley, Hume, and their followers. I have little doubt that the same is true mutatis mutandis of the attitude of many present-day philosophers towards the systems of monistic idealism which were fashionable at the beginning of this century. It is consoling to a philosopher's vanity not to pry too closely into the history of his subject, for otherwise he is liable to find that his discoveries have been anticipated and his fallacies refuted in advance by predecessors whom he has ignored or despised.

Those who, like the present writer, never had the privilege of meeting Sidgwick can infer from his writings, and still more from the characteristic philosophic merits of such pupils of his as McTaggart and Moore, how acute and painstaking a thinker and how inspiring a teacher he must have been. Yet he has grave defects as a writer which have certainly detracted from his fame. His style is heavy and involved, and he seldom allowed that strong sense of humour, which is said to have made him a delightful conversationalist, to relieve the uniform dull dignity of his writing. He incessantly refines, qualifies, raises objections, answers them, and then finds further objections to the answers. Each of these objections, rebuttals, rejoinders, and surrejoinders is in itself admirable, and does infinite credit to the acuteness and candour of the author. But the reader is apt to become impatient; to lose the thread of the argument: and to rise from his desk finding that he has read a great deal with constant admiration and now remembers little or nothing. The result is that Sidgwick probably has far less influence at present than he ought to have, and less than many writers, such as Bradley, who were as superior to him in literary style as he was to them in ethical and philosophical acumen. Even a thoroughly second-rate thinker like T. H. Green, by diffusing a grateful and comforting aroma of ethical "uplift", has probably made far more undergraduates into prigs than Sidgwick will ever make into philosophers.