Kautilya's Arthashastra 1.5.4

1.5.4

kriyā hi dravyaṃ vinayati nādravyam //

Discipline is of two kinds: artificial and natural; for instruction (kriya) can render only a docile being conformable to the rules of discipline, and not an undocile being (adravyam). The study of sciences can tame only those who are possessed of such mental faculties as obedience, hearing, grasping, retentive memory, discrimination, inference, and deliberation, but not others devoid of such faculties.