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121 the Spherical Earth in Plato's Phaedo WILLIAM M. CALDER

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121 the Spherical Earth in Plato's Phaedo WILLIAM M. CALDER in Plato's Phaedo The Spherical Earth WILLIAM M. CALDER III UITE recently 6 193-197) Professor T. G. Rosen- of the University of Washington has challenged the meyer traditional view that in the Phaedo Plato imagines the earth as a sphere. Rosenmeyer (henceforth R.) would rather have us believe that Plato is concerned (p. 193) with "an image, however vague, of a flat earth with a fixed horizon." The value of his ingenious essay is that it encourages us to reconsider many points that we were ever too prepared to accept as true without examination. Nevertheless, I still believe the traditional view must be correct and wish to defend it in the light of I R.'s arguments.' R. believes (p. 193) the problem can be divided into two parts: ( i ) Does Plato in the Phaedo ( I o8 e- i o9 a, 1 Iob sff, and Timaeus 40b-c and 62 dff.) think of the earth as a spherical body? and (2) "Granted he does, need his description of the earth, as a setting for his eschatological myth, conform with the spherical theory?" In sixteen lines R. disposes of (i) which "does not affect the answer to (2)." R., it seems, is quite prepared to believe that in i i o b S ff. Plato may be speaking of a spherical earth, while in III without a word of warning to his reader that he has discarded the spherical theory, he begins to speak in terms of a flat earth hypothesis. Until R. provides a Platonic parallel, it will be difficult to believe that so profound and sudden a contradiction would be tolerated by the ancient philosopher without some remark, however brief, of explanation. R.'s interpretation appears inconsistent with the careful, logical progression that we associate with the Socratic method. In a word R.'s ( 2) can only be flat if his ( i ) is flat also. Let us first attack then R.'s flat ( i ) . R. could have alleviated his task by not discussing the Timaeus passages, which "only prove that after years of associating with astronomers, Plato may have come to think in 121 spherical terrns ... " It need never be assumed and certainly can never be proved that the cosmography attributed to Timaeus of Locri in the Timaeus need have been intended by the author of the dialogue to be consistent with the cosmography attributed to Socrates in the Phaedo. That the earth of the Phaedo is spherical or flat can only be determined by a study of the evidence that Plato presents in the Phaedo. No infor- mation provided by a different interlocutor in a different literary work can legitimately influence our decision one way or the other. I confine my discussion therefore to the Phaedo. R. cavalierly dismisses with "ambiguous may " 1 well refer to a construct of concentric rings in the Ionian tradition... This remark neglects to consider Platonic usage. applied to solids means spherical, globular (see LSjs. Y. 2.b). For this sense in Plato LSJ cite the Phaedo passage and Smp 1 90 b where the word describes the unambiguously globular hermaphrodites. See also Ti. 5"5" awhere the word is used of a sphere and Parm. 1 3 7 ewhere it is applied to the earth. Professor Jaeger further adds two Aristotelian examples, where that author is using the vocabulary of the same scientific tradition as Plato and where the word certainly means spherical, namely Cael. 2. 14. 298a7 (of the earth) and Meteor. I. 1 2 . 3 48 a 3 6 (of hailstones).2 Furthermore, pace R., I feel that iaoppono5 and G'poLo4and indeed the whole passage I o 8 e 4- i o9 a 7 certainly favor, if not demand, the sphere concept. Socrates describes a spherical earth set within a spherical universe and kept in position by centripetal force.3 R. makes too little of the fact that Socrates' earth does not fall just because it is a sphere centered within a sphere. R's disc-shaped earth, if within a spherical universe, would have need of either air or some &vcíyx1Je; so as not to fall; but furthermore the text will not permit a disc within 122 .
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