principles are held to be insufficient, and demonstrative value is denied to the syllogism, how are we to prove satisfactorily the existence of God by deducing it, for instance, from the concept of motion and from the principle of causality, which to-day, for the modern habit of mind, have only the relative value of working hypotheses, and may to-morrow be summarily disowned at a stroke? And if this particular demonstration is held to be insufficient, how are we to arrive at the others—as to the necessity of supernatural revelation and positive religion, as to the divine nature of Christianity, truths which, according to the old apologetic, issue from it by a series of deductions? And, further, how are we to induce men to accept as rules of faith and of the religious life the eternal truths of Christianity, seeing that they have reached us in formulas and conceptions which are the genuine expression of a metaphysic no longer acknowledged as
