For Maimon's life held many more vicissitudes, but the profession of medicine was never of them. "I require of every man of sound mind that he should lay out for himself a plan of action," said the philosopher; and wandered to Breslau, to Amsterdam, to Potsdam, the parasite of protectors, the impecunious hack of publishers, the rebel of manners, the ingenious and honored metaphysician. When Kant declared he was the only one of his critics that understood _The Critique of Pure Reason_, Maimon returned to Berlin to devote himself to the philosophical work that was to give him a pinnacle apart among the Kantians. Goethe and Schiller made flattering advances to him. Berlin society was at his feet. But he remained to the end, shiftless and feckless, uncouth and unmanageable, and not seldom when the taverns he frequented were closed, he would wander tipsily through the sleeping streets meditating suicide, or arguing metaphysics with expostulant watchmen. "For all his mathematics," a friend said of him, "he never seems to think of the difference between _plus_ and _minus_ in money matters." "People like you, there's no use trying to help," said another, worn-out, when Maimon pleaded for only a few coppers. Yet he never acquired the beggar's servility, nay, was often himself the patron of some poorer hanger-on, for whom he would sacrifice his last glass of beer. Curt in his manners, he refused to lift his hat or embrace his acquaintances in cold blood. Nor would he wear a wig. Pure Reason alone must rule.