G. K. C. on tolerance

But modern tolerance is deafer than intolerance. The old religious authorities, at least, defined a heresy before they condemned it, and read a book before they burned it. But we are always saying to a Mormon or a Moslem — ‘Never mind about your religion, come to my arms.’ To which he naturally replies — ‘But I do mind about my religion, and I advise you to mind your eye.’
. . . . .
Historians seem to have completely forgotten the two facts — first, that men act from ideas; and second, that it might, therefore, be as well to discover which ideas.

—G. K. Chesterton, ‘Mormonism’