Some speculators have a short way of accounting for the Pagan religion: mere quackery, priestcraft, and dupery, say they; no sane man ever did believe it, — merely contrived to persuade other men, not worthy of the name of sane, to believe it! It will be often our duty to protest against this sort of hypothesis about men’s doings and history; and I here, on the very threshold, protest against it in reference to Paganism, and to all other isms by which man has ever for a length of time striven to walk in this world. They have all had a truth in them, or men would not have taken them up. Quackery and dupery do abound; in religions, above all in the more advanced decaying stages of religions, they have fearfully abounded: but quackery was never the originating influence in such things; it was not the health and life of such things, but their disease, the sure precursor of their being about to die!

Thomas Carlyle (1795-1881) Scottish essayist and historian

Lecture (1840-05-05), “The Hero as Divinity,” Home House, Portman Square, London
    (Source)

The lecture notes were collected by Carlyle into On Heroes, Hero-Worship, & the Heroic in History, Lecture 1, (1841).