I recognize that in his special belief the Christian Scientist is insane, because he does not believe as I do; but I hail him as my mate and fellow, because I am as insane as he insane from his point of view, and his point of view is as authoritative as mine and worth as much.

That is to say, worth a brass farthing.

Upon a great religious or political question, the opinion of the dullest head in the world is worth the same as the opinion of the brightest head in the world--a brass farthing.

How do we arrive at this?
It is simple.
The affirmative opinion of a stupid man is neutralized by the negative opinion of his stupid neighbor no decision is reached; the affirmative opinion of the intellectual giant Gladstone is neutralized by the negative opinion of the intellectual giant Newman--no decision is reached.

Opinions that prove nothing are, of course, without value any but a dead person knows that much.