Virtue begins by shunning vice; wisdom
By shunning folly.

[Virtus est vitium fugere et sapientia prima
stultitia caruisse.]

Horace (65–8 BC) Roman poet, satirist, soldier, politician [Quintus Horatius Flaccus]

Epistles [Epistularum, Letters], Book 1, ep. 1 “To Maecenas,” l. 41ff (1.1.41-42) (20 BC) [tr. Ferry (2001)]
    (Source)

(Source (Latin)). Other translations:

It is virtue, vice t'avoyde and wysedome chéefe of all
Follie to wante: these two ills lo do vex the at thy gall.
[tr. Drant (1567)]

'Tis Vertue, to flie Vice: and the first Stair
Of Wisdome, to want Folly.
[tr. Fanshawe; ed. Brome (1666)]

'Tis Vertue, Sir, to be but free from Vice,
And the first step tow'rds being truly Wise
Is to want folly.
[tr. Creech (1684)]

Even in our flight from vice some virtue lies;
And free from folly, we to wisdom rise.
[tr. Francis (1747)]

Vice to renounce is virtue's earliest rule,
Wisdom's first step is to lay aside the fool.
[tr. Howes (1845)]

It is virtue, to fly vice; and the highest wisdom, to have lived free from folly.
[tr. Smart/Buckley (1853)]

To fly from vice is virtue: to be free
From foolishness is wisdom's first degree.
[tr. Conington (1874)]

To fly from vice is virtue, says the sage,
Not to be foolish, wisdom's earliest stage.
[tr. Martin (1881)]

It is virtue to fly from vice, and the beginning of wisdom to be free from folly.
[tr. Elgood (1893)]

To flee vice is the beginning of virtue, and to have got rid of folly is the beginning of wisdom.
[tr. Fairclough (Loeb) (1926)]

Virtue means keeping from vice, and wisdom begins
When you stop being stupid.
[tr. Palmer Bovie (1959)]

Virtue begins with fleeing vice and wisdom starts
in being a fool no longer.
[tr. Fuchs (1977)]

Running when vice runs after you
Is the beginning of virtue; shaking
Foolishness off is the beginning
Of sense.
[tr. Raffel (1983)]

Virtue's first rule is "avoid vice," and wisdom's
"get rid of folly."
[tr. Rudd (2005 ed.)]

Virtue is to flee vice, and wisdoms’ beginning is
Freedom from foolishness.
[tr. Kline (2015)]