The mathematicians are well acquainted with the difference between pure science, which has only to do with ideas, and the application of its laws to the use of life, in which they are constrained to submit to the imperfections of matter and the influence of accidents.

How small of all that human hearts endure, That part which laws or kings can cause or cure! Still to ourselves in every place consigned, Our own felicity we make or find. With secret course, which no loud storms annoy, Glides the smooth current of domestic joy.

Gayety is to good-humor as perfumes to vegetable fragrance: the one overpowers weak spirits; the other recreates and revives them.

No government power can be abused long. Mankind will not bear it.

That the happiness of man may still remain imperfect, as wants in this place are easily supplied, new wants likewise are easily created; every man, in surveying the shops of London, sees numberless instruments and conveniencies, of which, while he did not know them, he never felt the need; and yet, when use has made them familiar, wonders how life could be supported without them. Thus it comes to pass, that our desires always increase with our possessions; the knowledge that something remains yet unenjoyed, impairs our enjoyment of the good before us.

With what hope can we endeavor to persuade the ladies that the time spent at the toilet is lost in vanity.

The common people do not accurately adapt their thoughts to objects; nor, secondly, do they accurately adapt their words to their thoughts; they do not mean to lie; but, taking no pains to be exact, they give you very false accounts. A great part of their language is proverbial; if anything rocks at all, they say it rocks like a cradle; and in this way they go on.