Their military training will ensure success in war, but they must maintain unity by not allowing the state to grow to large, and by ensuring that the measures for promotion and demotion from one class to another are carried out. Above all they must maintain the educational system unchanged; for on education everything else depends, and it is an illusion to imagine that mere legislation without it can effect anything of consequence.
PlatoWe must, if we are to be consistent, and if we re to have a real pedigree herd, mate the best of our men with the best of our women as often as possible, and the inferior men with the inferior women as seldom as possible, and keep only the offspring of the best.
Plato