In treating of property, Plato takes occasion to speak of property in slaves (VI 776, 777). They are to be treated with perfect justice; but, for their own sake, to be kept at a distance. The motive is not so much humanity to the slave, of which there are hardly any traces (although Plato allows that many in the hour of peril have found a slave more attached than members of their own family), but the self-respect which the freeman and citizen owes to himself (compare Republic VIII 549 A). If they commit crimes, they are doubly punished (IX 867, 868; VIII 844 E following); if they inform against illegal practices of their masters, they are to receive a protection, which would probably be ineffectual, from the guardians of the law; in rare cases they are to be set free (XI 932 D, E). Plato still breathes the spirit of the old Hellenic world, in which slavery was a necessity, because leisure must be provided for the citizen.
The education propounded in the Laws differs in several points from that of the Republic. Plato seems to have reflected as deeply and earnestly on the importance of infancy as Rousseau, or Jean Paul (compare the saying of the latter—“Not the moment of death, but the moment of birth, is probably the more important”). He would fix the amusements of children in the hope of fixing their characters in afterlife (VII 797, 8). In the spirit of the statesman who said, “Let me make the ballads of a country, and I care not who make their laws,” Plato would say, “Let the amusements of children be unchanged, and they will not want to change the laws” (VII 798 C). The “Goddess Harmonia” plays a great part in Plato’s ideas of education. The natural restless force of life in children, “who do nothing but roar until they are three years old,” is gradually to be reduced to law and order (VII 792 A; compare II 653 E following). As in the Republic, he fixes certain forms in which songs are to be composed: (1) they are to be strains of cheerfulness and good omen; (2) they are to be hymns or prayers addressed to the Gods; (3) they are to sing only of the lawful and good (VII 800, 801). The poets are again expelled or rather ironically invited to depart; and those who remain are required to submit their poems to the censorship of the magistrates (VII 817). Youth are no longer compelled to commit to memory many thousand lyric and tragic Greek verses; yet, perhaps, a worse fate is in store for them. Plato has no belief in “liberty of prophesying”; and having guarded against the dangers of lyric poetry, he remembers that there is an equal danger in other writings. He cannot leave his old enemies, the Sophists, in possession of the field; and therefore he proposes that youth shall learn by heart, instead of the compositions of poets or prose writers, his own inspired work on laws (VII 810, 811). These, and music and mathematics, are the chief parts of his education.
Mathematics are to be cultivated, not as in the Republic with a view to the science of the idea of good—though the higher use of them is not altogether excluded (VII 818 C, D)—but rather with a religious and political aim. They are a sacred study which teaches men how to distribute the portions of a state (V 737, 8; 746 D following), and which is to be pursued in order that they may learn not to blaspheme about astronomy (VII 821 C). Against three mathematical errors Plato is in profound earnest. First, the error of supposing that the three dimensions of length, breadth, and height, are really commensurable with one another (VII 820). The difficulty which he feels is analogous to the difficulty which he formerly felt about the connection of ideas, and is equally characteristic of ancient philosophy: he fixes his mind on the point of difference, and cannot at the same time take in the similarity. Secondly, he is puzzled about the nature of fractions: in the Republic (VII 525 E), he is disposed to deny the possibility of their existence. Thirdly, his optimism leads him to insist (unlike the Spanish king who thought that he could have improved on the mechanism of the heavens) on the perfect or circular movement of the heavenly bodies (VII 821, 822). He appears to mean, that instead of regarding the stars as overtaking or being overtaken by one another, or as planets wandering in many paths, a more comprehensive survey of the heavens would enable us to infer that they all alike moved in a circle around a centre (compare “Timaeus” 40 following; Republic X 617). He probably suspected, though unacquainted with the true cause, that the appearance of the heavens did not agree with the reality: at any rate, his notions of what was right or fitting easily overpowered the results of actual observation. To the early astronomers, who lived at the revival of science, as to Plato, there
