Immanuel Kant's Critique of Pure Reason — trans. F. Max Müller

The sceptical errors of that otherwise singularly acute thinker arose chiefly from a defect, which he shared, however, in common with all dogmatists, namely, of not having surveyed systematically all kinds of synthesis a priori of the understanding. For in doing this he would, without mentioning others, have discovered, for instance, the principle of permanency as one which, like causality, anticipates experience. He would thus have been able also to fix definite limits to the understanding in its attempts at expansion a priori and to pure reason. He only narrows the sphere of our understanding, without definitely limiting it, and produces a general mistrust, but no definite knowledge of that ignorance which to us is inevitable. He only subjects certain principles of the understanding to his censura^ but does not place the understanding, with reference to all its faculties, on the balance of criticism. He is not satisfied with denying to the understanding what in reality it does not possess, but goes on to deny to it all power of expanding a priori, though he has never really tested all its powers. For this reason, what always defeats scepticism has happened to Hume also, namely.

6i6 Discipline of Pure Reason that he himself becomes subject to scepticism, because his objections rest on facts only which are contingent, and not on principles which alone can force a surrender of the right of dogmatical assertion. [p. 'j6Z'\

As, besides this, he does not sufficiently distinguish between the well-grounded claims of the understanding and the dialectical pretensions of reason, against which, however, his attacks are chiefly directed, it so happens that reason, the peculiar tendency of which has not in the least been destroyed, but only checked, does not at all consider itself shut out from its attempts at expansion, and can never be entirely turned away from them, although it may be punished now and then. Mere attacks only provoke counter attacks, and make us more obstinate in enforcing our own views. But a complete survey of all that is really our own, and the conviction of a certain though a small possession, make us perceive the vanity of higher claims, and induce us, after surrendering all disputes, to live contentedly and peacefully within our own limited, but undisputed domain.

These sceptical attacks are not only dangerous, but even destructive to the uncritical dogmatist who has not measured the sphere of his understanding, and has not, therefore, determined, according to principles, the limits of his own possible knowledge, and does not know beforehand how much he is really able to achieve, but thinks that he is able to find all this out by a purely tentative method. For if he has been found out in one single assertion of his, which he cannot justify, or the fallacy of which he cannot evolve according to prin- [p. 769] ciples, suspicion falls on all his assertions, however plausible they may appear.

Discipline of Pure Reason 617

And thus the sceptic is the true schoolmaster to lead the dogmatic speculator towards a sound criticism of the understanding and of reason. When he has once been brought there, he need fear no further attacks, for he has learnt to distinguish his own possession from that which lies completely beyond it, and on which he can lay no claim, nor become involved in any disputes regarding it. Thus the sceptical method, though it cannot in itself satisfy with regard to the problems of reason, is nevertheless an excellent preparation in order to awaken its circumspection, and to indicate the true means whereby the legitimate possessions of reason may be secured against all attacks.

DISCIPLINE OF PURE REASON

Section III The Discipline of Pure Reason with Regard to Hypotheses

As then the criticism of our reason has at last taught us so much at least, that with its pure and speculative use we can arrive at no knowledge at all, would not this seem to open a wide field for hypotheses, as, where we cannot assert with certainty, we are at all events at liberty to form guesses and opinions }

If the faculty of imagination is not simply to [p. 770] indulge in dreams, but to invent and compose under the strict surveillance of reason, it is necessary that there should always be something perfectly certain, and not only invented or resting on opinion, and that is the possibility of the object itself. If that is once given, it is

6i8 Discipline of Pure Reason then allowable, so far as its reality is concerned, to have recourse to opinion, which opinion, however, if it is not to be utterly groundless, must be brought in connection with what is really given and therefore certain, as its ground of explanation. In that case, and in that case only, can we speak of an hypotJiesis.