A woman is no sooner ours than we are no longer hers.

One man may have some special knowledge at first-hand about the character of a river or a spring, who otherwise knows only what everyone else knows. Yet to give currency to this shred of information, he will undertake to write on the whole science of physics. From this fault many great troubles spring.

Learning is not to be tacked to the mind, but we must fuse and blend them together, not merely giving the mind a slight tincture, but a thorough and perfect dye. And if we perceive no evident change and improvement, it would be better to leave it alone; learning is a dangerous weapon, and apt to wound its master if it be wielded by a feeble hand, and by one not well acquainted with its use.

Nothing else but an insatiate thirst of enjoying a greedily desired object.

Every man bears the whole stamp of the human condition.

I study myself more than any other subject. That is my metaphysics, that is my physics.

We are all of us richer than we think we are.