The difference between a man who is led by opinion or emotion and one who is led by reason. The former, whether he will or not, performs things of which he is entirely ignorant; the latter is subordinate to no one, and only does those things which he knows to be of primary importance in his life, and which on that account he desires the most; and therefore I call the former a slave, but the latter free.

Reason, in a strict sense, as meaning the judgment of truth and falsehood, can never, of itself, be any motive to the will, and can have no influence but so far as it touches some passion or affection. Abstract relations of ideas are the object of curiosity, not of volition. And matters of fact, where they are neither good nor evil, where they neither excite desire nor aversion, are totally indifferent, and whether known or unknown, whether mistaken or rightly apprehended, cannot be regarded as any motive to action.

Philosophy would render us entirely Pyrrhonian, were not nature too strong for it.

A man who has cured himself of all ridiculous prepossessions, and is fully, sincerely, and steadily convinced, from experience as well as philosophy, that the difference of fortune makes less difference in happiness than is vulgarly imagined; such a one does not measure out degrees of esteem according to the rent-rolls of his acquaintance. ... his internal sentiments are more regulated by the personal characters of men, than by the accidental and capricious favors of fortune.

Battles, revolutions, pestilence, famine, and death, are never the effect of those natural causes, which we experience. Prodigies,omens, oracles, judgments, quite obscure the few natural events, that are intermingled with them. But as the former grow thinner every pagewe soon learn, that there is nothing mysterious or supernatural in the case, but that all proceeds from the usual propensity of mankind towards the marvellous, and that, though this inclination may at intervals receive a check from sense and learning, it can never be thoroughly extirpated.

There is not to be found, in all history, any miracle attested by a sufficient number of men, of such unquestioned good sense, education and learning, as to secure us against all delusion in themselves.

When I shall be dead, the principles of which I am composed will still perform their part in the universe, and will be equally useful in the grand fabric, as when they composed this individual creature. The difference to the whole will be no greater betwixt my being in a chamber and in the open air. The one change is of more importance to me than the other; but not more so to the universe.