In the campaign for absolute freedom of thought, for the duty of not believing anything except on sufficient evidence, Huxley was frequently met by an argument of superficial strength, and which no doubt was in the minds of many of his clerical opponents. In the minds of a majority of people, it was said, and particularly of slightly educated people, the reasons for right conduct and the distinctions between right and wrong are firmly associated with the Bible and with religion. If you allow doubts as to the absolute veracity of the Bible, or as to the supernatural origin of religion to reach such persons, you run a grave risk that they will reflect the uncertainty on the canons of morality. In taking from them what you believe to be false, inevitably you will unsettle their ideas on moral questions although you might be in full agreement as to these moral questions. Huxley refused to accept the asserted association between morality and particular metaphysical or religious doctrines.
“Many ingenious persons now appear to consider that the incompatibility of pantheism, of materialism, and of any doubt about the immortality of the soul, with religion and morality is to be held as an axiomatic truth. I confess that I have a certain difficulty in accepting this dogma. For the Stoics were notoriously materialists and pantheists of the most extreme character; and while no strict Stoic believed in the eternal duration of the individual soul, some even denied its persistence after death. Yet it is equally certain, that, of all gentile philosophies, Stoicism exhibits the highest ethical development, is animated by the most religious spirit, and has exerted the profoundest influence upon the moral and religious development not merely of the best men among the Romans, but among the moderns down to our own day.”
He held the view now generally taken by students of the history of man, that standards of conduct and religious beliefs arose in separate ways and developed independently, and that it was only comparatively recently that “religion took morality under its protection.” But he met the argument in a still more direct fashion by rejecting entirely the possibility or advisability of founding any system of ethics upon a false basis.