So far as it can be historically traced, the intellectual influence of Christianity was relatively at its best when it began to be propounded as a creed in critical relation to Judaism. Intellectual gain was checked as soon as it became a substantive creed, demanding submissive acceptance. From that point forward it becomes a restraint on intellectual freedom, save insofar as it stirred believers to a one-sided criticism of pagan beliefs, a process of which the educational effect was promptly annulled by a veto on its extension to the beliefs of the critics. It has been argued indeed that modern science has been signally advanced by the mental bias that goes with monotheism; but the historical fact is that Jewish monotheism was much less friendly to science than Babylonian polytheism; that the beginnings of Greek science were among polytheists and, perhaps, atheists; that Saracen monotheism owed its scientific stimulus to the recovered thought of polytheistic Greece; and that, whatever impulse a truly monotheistic philosophy may have given to modern science, the usual influence of Christian belief has been to override the idea of invariable causation in nature. Even after the belief in recurrent miracles is disavowed, the doctrine and practice of prayer remain to represent the old concept. On the other hand, the kind of violence done to the instinct for concrete or historical truth by the frauds and delusions of the early and medieval Church, though greatly attenuated in modern times, has never ended. Critical judgment has only slowly recovered the strength and stature it had in the pre-Christian world; and wherever faith has plenary rule such judgment is liable to arbitrary interdict. It is true that even in the nineteenth century some great servants of science have been either orthodox Christians or devout theists. Faraday and Joule, Pasteur and Kelvin, are cases in point. But instead of the religious creed having in such cases furnished the cue or the motive to the scientific work done, it is found to be out of all logical relation to it, and to be a mere obstruction to the scientific use of the reason on the religious problem itself.