Plato, Republic

1 Cf. Bruno apudHöffding, History of Modern Philosophy, i. 125 and 128, and Galileo, ibid. i. 178; also Lucretius v. 302-305.

2 Plato was right against the view that Aristotle imposed on the world for centuries. We should not therefore say with Adam that he would have attached little significance to the perturbations of Neptune and the consequent discovery of Uranus. It is to Plato that tradition attributes the problem of accounting by the simplest hypothesis for the movement of the heavenly bodies and “saving the phenomena.” The alleged contradiction between this and Laws 821 B ff. and Tim. 41 A is due to a misapprehension. That the stars in their movements do not perfectly express the exactness of mathematical conceptions is no more than modern astronomers say. In the Laws passage Plato protests against the idea that there is no law and order governing the movement of the planets, but that they are “wandering stars,” as irregular in their movements as they seem. In the Timaeus he is saying that astronomy or science took its beginning from the sight and observation of the heavenly bodies and the changing seasons. In the RepublicPlato's purpose is to predict and encourage a purely mathematical astronomy and the indicate its place in the type of education which he wishes to give his guardians. There is not the slightest contradiction or change of opinion in the three passages if interpreted rightly in their entire context.

3 The meaning is not appreciably affected by a slight doubt as to the construction of ζητεῖν. It is usually taken with ἄτοπον(regarded as neuter), the meaning being that the Philosophic astronomer will think it strange to look for the absolute truth in these things. This double use of ἄτοπον is strained and it either makes παντὶ τρόπῳ awkward or attributes to Plato the intention of decrying the concrete study of astronomy. I think ζητεῖν etc. are added by a trailing anacoluthon such as occurs elsewhere in the Republic. Their subject is the real astronomer who, using the stars only as “diagrams” or patterns (529 D), seeks to learn a higher exacter mathematical truth than mere observation could yield. Madvig's ζητήσει implies a like view of the meaning but smooths out the construction. But my interpretation of the passage as a whole does not depend on this construction. If we make ζητεῖν depend on ἄτοπον(neuter)ἡγήσεται, the meaning will be that he thinks it absurd to expect to get that higher truth from mere observation. At all events Plato is not here objecting to observation as a suggestion for mathematical studies but to its substitution for them, as the next sentence shows.

4 That is just what the mathematical astronomy of today does, and it is a πολλαπλάσιον ἔργον compared with the merely observational astronomy of Plato's day. Cf. the interesting remarks of Sir James Jeans, apudS. J. Woolf, Drawn from Life, p. 74: “The day is gone when the astronomer's work is carried on only at the eyepiece of a telescope. Naturally, observations must be made, but these must be recorded by men who are trained for that purpose, and I am not one of them,” etc. Adam's quotation of Browning's “Abt Vogler” in connection with this passage will only confirm the opinion of those who regard Plato as a sentimental enemy of science.