Do your duty, nothing else. Marcus Aurelius 6.22

It is important to know how to avoid doing what is none of our business. Especially in today's world, when events conspire to make us know more than we can or should.

Ἐγὼ τὸ ἐμαυτοῦ καθῆκον ποιῶ, τὰ ἄλλα με οὐ περισπᾷ· ἤτοι γὰρ ἄψυχα ἢ ἄλογα ἢ πεπλανημένα καὶ τὴν ὁδὸν ἀγνοοῦντα.

I do my duty, the work that belongs properly to me. Other matters do not draw me aside, for they are either lifeless or witless nonentities to me, or else they are far removed from my path, which they know not.