History of Western Philosophy: Collectors Edition

by Bertrand Russell

The first and best evidence is that of Archimedes, who, as we have seen, was a younger contemporary of Aristarchus. Writing to Gelon, King of Syracuse, he says that Aristarchus brought out ‘a book consisting of certain hypotheses’, and continues: ‘His hypotheses are that the fixed stars and the sun remain unmoved, that the earth revolves about the sun in the circumference of a circle, the sun lying in the middle of the orbit.’ There is a passage in Plutarch saying that Cleanthes ‘thought it was the duty of the Greeks to indict Aristarchus of Samos on the charge of impiety for putting in motion the Hearth of the Universe (i.e. the earth), this being the effect of his attempt to save the phenomena by supposing the heaven to remain at rest and the earth to revolve in an oblique circle, while it rotates, at the same time, about its own axis’. Cleanthes was a contemporary of Aristarchus, and died about 232 B.C. In another passage, Plutarch says that Aristarchus advanced this view only as a hypothesis, but that his successor Seleucus maintained it as a definite opinion. (Seleucus flourished about 150 B.C.) Aëtius and Sextus Empiricus also assert that Aristarchus advanced the heliocentric hypothesis, but do not say that it was set forth by him only as a hypothesis. Even if he did so, it seems not unlikely that he, like Galileo two thousand years later, was influenced by the fear of offending religious prejudices, a fear which the attitude of Cleanthes (mentioned above) shows to h...