48; R., p. 44) assured “that no instance can show, and consequently there can be no empirical proof, that an Imperative of this sort exists everywhere.” And further, on p. 49 (R., p. 45), we read, “that the reality of the Categorical Imperative is not a fact of experience.” Now if we put all this together, we can hardly avoid the suspicion that Kant is jesting at his readers' expense.

But although this practice may be allowed by the present philosophical public of Germany, and seem good in their eyes, yet in Kant's time it was not so much in vogue; and besides, Ethics, then, as always, was precisely the subject that least of all could lend itself to jokes. Hence we must continue to hold the conviction that what can neither be conceived as possible, nor proved as actual, is destitute of