Ecclesiasticism in science is only unfaithfulness to truth.
If the blind acceptance of authority appears to him in its true colours, as mere private judgment in excelsis, and if he have the courage to stand alone, face to face with the abyss of the eternal and unknowable, let him be content, once for all, not only to renounce the good things promised by "Infallibility," but even to bear the bad things which it prophesies; content to follow reason and fact in singleness and honesty of purpose, wherever they may lead, in the sure faith that a hell of honest men will, to him, be more endurable than a paradise full of angelic shams.
History warns us that it is the customary fate of new truths to begin as heresies and to end as superstitions.
The struggle for existence holds as much in the intellectual as in the physical world. A theory is a species of thinking, and its right to exist is coextensive with its power of resisting extinction by its rivals.
The scientific spirit is of more value than its products, and irrationally held truths may be more harmful than reasoned errors.