Indeed so far are use and habit from being causes of pleasure merely as such, that the effect of constant use is to make all things of whatever kind entirely unaffecting.

For as use at last takes off the painful effect of many things, it reduces the pleasurable effect in others in the same manner, and brings both to a sort of mediocrity and indifference.

Very justly is use called a second nature; and our natural and common state is one of absolute indifference, equally prepared for pain or pleasure.

But when we are thrown out of this state, or deprived of anything requisite to maintain us in it; when this chance does not happen by pleasure from some mechanical cause, we are always hurt.

It is so with the second nature, custom, in all things which relate to it.