reason approved. The days of persecution for opinion's sake seem to have passed away forever. The ridicule, discredit, and oppression that dogged the careers of Galileo, of Savonarola, of Harvey, of Jenner, and so many others whose names stand in the long martyrology of science, are hardly intelligible to the present generation, which has at least some reason to boast of its love of truth for truth's sake, and its freedom from prejudice. Yet it may well be questioned whether the charity and liberality that we claim for ourselves as virtues are not rather a result of the equality of civil rights in the modern world. It compels us to be tolerant of differences of opinion, to repress the invective that formerly was poured upon opponents, to conceal the claws which the animal in human nature too frequently incites us to employ against antagonists. It is a sad but unquestionable fact that the most virulent adversaries are men whose opinions and beliefs are least radically opposed. They are ready to grapple each other in deadly conflict over the meaning of some word, the significance of some fact, which neither understands, and yet will look with equanimity and even charity upon persons who agree with neither of them.
If liberty and equality under law effected nothing more than a compulsory deference, if not respect, for the habits, opinions, and even the prejudices of other men, they would justify their claim to the fetish-like worship they now command. It may be truly said of them that they refine men's manners and prevent their being brutal. But while there are limits within which differences of opinion should be courteously treated there is beyond them a region—"an abysmal valley dolorous" (Inferno, iv. 8)—filled with strange shapes, grotesque and vile, among which flit others shadowy and intangible. The former strive for recognition with brutal boldness; the latter with stealthy and insinuating manœuvres, and are apt to wheedle the self-sufficient rather than the ignorant into their snares. Upon the one the true physician looks with disgust, upon the other with contempt, striving meanwhile to keep his own skirts clear from the stains of similar coarseness or folly. He knows how great a heritage of knowledge and wisdom has come down to him through the ages, and strives to preserve it for his successors untainted by the defects and errors which it is impossible for any branch of knoweldge or any department of art to escape.
To this end it is important for him, and for us, to learn what are the boundaries of his field of knowledge, and what are the limits of his power within it. Above all, he should recognize the contrasts between
