We alone are right-minded; everyone else is wrong.

[μόνοι γὰρ εὖ φρονοῦμεν, οἱ δ᾽ ἄλλοι κακῶς.]

Euripides (485?-406? BC) Greek tragic dramatist

Bacchæ [Βάκχαι], l. 196 [Teiresias/Τειρεσίας] (405 BC) [tr. Robinson (2014)]
    (Source)

When asked by Cadmus about being the only men of Thebes attending the Bacchanal. (Source (Greek)). Alternate translation:

          Because ourselves alone
Are truly wise, but others judge amiss.
[tr. Wodhull (1809)]

Yes, for we alone think rightly, the rest wrongly.
[tr. Buckley (1850)]

All else misjudge; we only are the wise.
[tr. Milman (1865)]

Alone: For we are wise, the rest are fools.
[tr. Rogers (1872), l. 179]

Yea, for we alone are wise, the rest are mad.
[tr. Coleridge (1891)]

Yea, we alone are wise; the rest be fools.
[tr. Way (1898)]

Aye, Thebes is blinded. Thou and I can see.
[tr. Murray (1902)]

          They are all blind.
Only we can see.
[tr. Arrowsmith (1960)]

Yes, for only we are sane -- the rest are mad.
[tr. Kirk (1970)]

We are the only men right-minded; the rest are perverse.
[tr. Vellacott (1973)]

We alone think well, the others ill.
[tr. Neuburg (1988)]

The only ones with healthy minds. The rest are sick.
[tr. Cacoyannis (1982)]

Only we think right. The others vilely.
[tr. Blessington (1993)]

Yes, since only we reason well. The rest are fools!
[tr. Esposito (1998)]

The only ones in our right minds. The rest are mad.
[tr. Woodruff (1999)]

Yes, only we have any sense, the rest have none.
[tr. Gibbons/Segal (2000)]

Yes, we alone have sense, the others none.
[tr. Kovacs (2002)]

Yes, Kadmos because we are the only ones who can think straight. The rest of them? They are all wrong!
[tr. Theodoridis (2005)]

We alone've got it right; the others, wrongly.
[tr. Valerie (2005)]

          Yes, indeed,
for we're the only ones whose minds are clear.
As for the others, well, their thinking's wrong.
[tr. Johnston (2008), l. 247ff]

The rest are blind. Only we can see.
[tr. Robertson (2014)]

We’re the only ones wise enough. The rest ... less so.
[tr. Pauly (2019)]

Of course; no one else has enough sense.
[tr. Behr/Foster (2019)]

We alone are sensible, all the others foolish.
[tr. Buckley/Sens/Nagy (2020)]