Reason (n.) is what separates us from wild beasts and from sheep, Epictetus said — so take care never to act like a wild beast.
Reason (n.) is measured not by length or height but by the decisions of its will — and there you are not inferior to the gods.
Reason (n.) is great not in height or length but in the quality of its judgements, and by that measure you are no smaller than the gods.
Reason (n.) was surely not given us by the gods so that we might be more miserable than the irrational ravens, who leave home without a pang.
Reason (n.) is the only art that can judge itself: grammar tells you how to write the letter, never whether to send it.
Reason (n.) is made of the very impressions it judges, which is why it alone can contemplate itself.
Reason (n.) is the one possession the rich neglect: they master marble halls and hunting dogs, but leave the governing faculty dirty and neglected.
Reason (n.) is the faculty that rules the use of all the others: the flute-player's skill can tell you how to play, never whether you ought to.
Reason (n.) cannot be checked by anything but reason; call in a second reason to audit the first and you need a third, and the regress never ends.
Reason (n.) is the only faculty that can examine itself: grammar tells you how to spell the letter to your friend, but never whether you ought to write it.
Reason (n.) makes pain bearable: to a rational being only the irrational is unendurable, and once Spartans learn a flogging is rational, they take it.
Reason (n.) is itself a collection of impressions, which is why it alone can turn and examine itself, as leatherwork cannot examine itself in hides.
Reason (n.) is the one faculty that studies itself as well as everything else: grammar tells you how to spell a letter to a friend, but never whether to write it.
Reason (n.) is measured not by length or height but by the worth of its judgments: in body you are a speck of the All, in reason no lesser than the gods.