in order that they might be rightfully popular after they have attained a definite insight.

We need only look at the attempts of moralists in that favourite fashion, and we shall find at one time the special constitution of human nature (including, however, the idea of a rational nature generally), at one time perfection, at another happiness, here moral sense, there fear of God. a little of this, and a little of that, in marvellous mixture, without its occurring to them to ask whether the principles of morality are to be sought in the knowledge of human nature at all (which we can have only from experience); or, if this is not so, if these principles are to be found altogether a priori, free from everything empirical, in pure rational concepts only and nowhere else, not even in the smallest degree; then