If by gaining knowledge we destroy our health, we labour for a thing that will be useless in our hands.

I attribute the little I know to my not having been ashamed to ask for information, and to my rule of conversing with all descriptions of men on those topics that form their own peculiar professions and pursuits.

Men in great fortunes are strangers to themselves, and while they are in the puzzle of business, they have no time to tend their health either of body or mind.

The thoughts that come often unsought, and, as it were, drop into the mind, are commonly the most valuable of any we have.

He would be laughed at, that should go about to make a fine dancer out of a country hedger, at past fifty. And he will not have much better success, who shall endeavour, at that age, to make a man reason well, or speak handsomely, who has never been used to it, though you should lay before him a collection of all the best precepts of logic or oratory.

[I]t being reasonable and just, I should have a right to destroy that which threatens me with destruction: for by the fundamental law of nature, man being to be preserved as much as possible, when all cannot be preserved, the safety of the innocent is to be preferred: and one may destroy a man who makes war upon him, or has discovered an enmity to his being, for the same reason that he may kill a Wolf or a lion.

If to break loose from the bounds of reason, and to want that restraint of examination and judgment which keeps us from choosing or doing the worst, be liberty, true liberty, madmen and fools are the only freemen: but yet, I think, nobody would choose to be mad for the sake of such liberty, but he that is mad already.