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ἀριθμητική

Ἐὰν ᾖς φιλομαθής, ἔσει πολυμαθής -> If you are studious, you will become learned.
Isocrates, 1.18

Russian (Dvoretsky)

ἀριθμητική: ἡ (sc. τέχνη) искусство счета, учение о числах, арифметика Plat., Arst.