These are, perhaps, the only things we are agreed about; but, although they are so few, they are of inestimable value, because they make an infallible standard of sanity.

Whosoever accepts them him we know to be substantially sane; sufficiently sane; in the working essentials, sane.

Whoever disputes a single one of them him we know to be wholly insane, and qualified for the asylum.
Very well, the man who disputes none of them we concede to be entitled to go at large.

But that is concession enough.

We cannot go any further than that; for we know that in all matters of mere opinion that same man is insane--just as insane as we are; just as insane as Shakespeare was.
We know exactly where to put our finger upon his insanity: it is where his opinion differs from ours.
That is a simple rule, and easy to remember.