Aristarchus of Samos

The Ancient Copernicus

Sir Thomas Heath

• Publisher: Dover Publications
• Year: 2014
• ISBN:
  9780486150819
• Topic: Physical Sciences
• Subtopic: Astronomy & Astrophysics

"A most welcome addition to the literature of astronomical history." — Nature
"A most important contribution to the early history of Greek thought and a notable monument of English scholarship." — Journal of Hellenic Studies
This classic work traces Aristarchus of Samos's anticipation by two millennia of Copernicus's revolutionary theory of the orbital motion of the earth. Heath's history of astronomy ranges from Homer and Hesiod to Aristarchus and includes quotes from numerous thinkers, compilers, and scholasticists from Thales and Anaximander through Pythagoras, Plato, Aristotle, and Heraclides. 34 figures.

PART I

GREEK ASTRONOMY TO ARISTARCHUS OF SAMOS

I

SOURCES OF THE HISTORY

THE history of Greek astronomy in its beginnings is part of the history of Greek philosophy, for it was the first philosophers, Ionian, Eleatic, Pythagorean, who were the first astronomers. Now only very few of the works of the great original thinkers of Greece have survived. We possess the whole of Plato and, say, half of Aristotle, namely, those of his writings which were intended for the use of his school, but not those which, mainly composed in the form of dialogues, were in a more popular style. But the whole of the pre-Socratic philosophy is one single expanse of ruins;¹ so is the Socratic philosophy itself, except for what we can learn of it from Plato and Xenophon.

But accounts of the life and doctrine of philosophers begin to appear quite early in ancient Greek literature (cf. Xenophon, who was born between 430 and 425 B.C.); and very valuable are the allusions in Plato and Aristotle to the doctrines of earlier philosophers; those in Plato are not very numerous, but he had the power of entering into the thoughts of other men and, in stating the views of early philosophers, he does not, as a rule, read into their words meanings which they do not convey. Aristotle, on the other hand, while making historical surveys of the doctrines of his predecessors a regular preliminary to the statement of his own, discusses them too much from the point of view of his own system; often even misrepresenting them for the purpose of making a controversial point or finding support for some particular thesis.

From Aristotle’s time a whole literature on the subject of the older philosophy sprang up, partly critical, partly historical. This again has perished except for a large number of fragments. Most important for our purpose are the notices in the Doxographi Graeci, collected and edited by Diels.² The main source from which these retailers of the opinions of philosophers drew, directly or indirectly, was the great work of Theophrastus, the successor of Aristotle, entitled Physical Opinions

. It would appear that it was Theophrastus’s plan to trace the progress of physics from Thales to Plato in separate chapters dealing severally with the leading topics. First the leading views were set forth on broad lines, in groups, according to the affinity of the doctrine, after which the differences between individual philosophers within the same group were carefully noted. In the First Book, however, dealing with the Principles, Theophrastus adopted the order of the various schools, Ionians, Eleatics, Atomists, &c., down to Plato, although he did not hesitate to connect Diogenes of Apollonia and Archelaus with the earlier physicists, out of their chronological order; chronological order was indeed, throughout, less regarded than the connexion and due arrangement of subjects. This work of Theophrastus was naturally the chief hunting-ground for those who collected the ‘opinions’ of philosophers. There was, however, another main stream of tradition besides the doxographic; this was in the different form of biographies of the philosophers. The first to write a book of ‘successions’

of the philosophers was Sotion (towards the end of the third century B.C.); others who wrote ‘successions’ were a certain Antisthenes (probably Antisthenes of Rhodes, second century B.C.), Sosicrates, and Alexander Polyhistor. These works gave little in the way ol doxography, but were made readable by the incorporation of anecdotes and apophthegms, mostly unauthentic. The work of Sotion and the ‘Lives of Famous Men’ by Satyrus (about 160 B.C.) were epitomized by Heraclides Lembus. Another writer of biographies was the Peripatetic Hermippus of Smyrna, known as the Callimachean, who wrote about Pythagoras in at least two Books, and is quoted by Josephus as a careful student of all history.³ Our chief storehouse of biographical details derived from these and all other available sources is the great compilation which goes by the name of Diogenes Laertius (more properly Laertius Diogenes). It is a compilation made in the most haphazard way, without the exercise of any historical sense or critical faculty. But its value for us is enormous because the compiler had access to the whole collection of biographies which accumulated from Sotion’s time to the first third of the third century A. D. (when Diogenes wrote), and consequently we have in him the whole residuum of this literature which reached such dimensions in the period.

In order to show at a glance the conclusions of Diels as to the relation of the various representatives of the doxographic and biographic traditions to one another and to the original sources I append a genealogical table⁴:

Fig. 1

Only a few remarks need be added, ‘Vetusta Placita’ is the name given by Diels to a collection which has disappeared, but may be inferred to have existed. It adhered very closely to Theophrastus, though it was not quite free from admixture of other elements. It was probably divided into the following main sections: I. De principiis; IL De mundo; III. De sublimibus; IV. De terrestribus; V. De anima; VI. De corpore. The date is inferred from the facts that the latest philosophers mentioned in it were Posidonius and Asclepiades, and that Varro used it. The existence of the collection of Aëtius (De placitis,

) is attested by Theodoretus (Bishop of Cyrus), who mentions it as accessible, and who certainly used it, since his extracts are more complete and trustworthy than those of the Placita Philosophorum and Stobaeus. The compiler of the Placita was not Plutarch, but an insignificant writer of about the middle of the second century A.D., who palmed them off as Plutarch. Diels prints the Placita in parallel columns with the corresponding parts of the Eclogae, under the title of Aëtii Placita; quotations from the other writers who give extracts are added in notes at the foot of the page. So far as Cicero deals with the earliest Greek philosophy, he must be classed with the doxographers; both he and Philodemus (De pietate,

, fragments of which were discovered on a roll at Herculaneum) seem alike to have used a common source which...