Madness in its first stage--monomania--is a lack of proportion.

So long as this is general, it is not always noticeable, for the uninspired onlooker is without the necessary means of comparison.

But in monomania the errant faculty protrudes itself in a way that may not be denied.

It puts aside, obscures, or takes the place of something else--just as the head of a pin placed before the centre of the iris will block out the whole scope of vision.

The most usual form of monomania has commonly the same beginning as that from which Edgar Caswall suffered--an over-large idea of self-importance.