<head>III. Polybius's Criticism of previous Geographical Writers</head>Polybius in his account of the geography of Europe says that he dismisses older authors, but that he will examine those who find fault with them, Dicaearchus and Eratosthenes, the latest author who has dealt with geography,
and Pytheas who has led many people into error by saying that he traversed the whole of <a class="linkToPlace" target="_blank" href="/place?placename=Britain&groupId=409&placeId=759">Britain</a> on foot, giving the island a circumference of forty thousand stades,
and telling us also about <a class="linkToPlace" target="_blank" href="/place?placename=Thule&groupId=1032&placeId=1820">Thule</a>, those regions in which there was no longer any proper land nor sea nor air, but a sort of mixture of all three of the consistency of a jelly-fish in which one can neither walk nor sail, holding everything together, so to speak.
He says he himself saw this jellyfish-like substance but the rest he derives from hearsay. That is the account that Pytheas gives, and he tells us that he came back thence and starting again followed the whole shore of the ocean from <a class="linkToPlace" target="_blank" href="/place?placename=Cadiz&groupId=103&placeId=338">Cadiz</a> to the river Tanaïs. Polybius, then, says that it is in itself incredible that a private man and a poor man should have traverse such vast distances in a ship or on foot, but that Eratosthenes, while doubting if one should believe this, still believes in the account of <a class="linkToPlace" target="_blank" href="/place?placename=Britain&groupId=409&placeId=759">Britain</a> and the neighbourhood of <a class="linkToPlace" target="_blank" href="/place?placename=Gades&groupId=594&placeId=1105">Gades</a> and the rest of <a class="linkToPlace" target="_blank" href="/place?placename=Spain&groupId=983&placeId=1735">Spain</a>. But Polybius says it is far better to believe the Messenian Euhemerus than Pytheas, for Euhemerus says that he sailed only to one country, Panchaia, but Pytheas says that he personally visited the whole northern coast of Europe as far as the ends of the world, a thing we would not even believe of Hermes himself if he told us so.
Eratosthenes, however, he says, calles Euhemerus a Bergaean, but believes Pytheas whom not even Dicaearchus believed.
Now to say "whom not even Dicaearchus believed" is ridiculous, as if we should take him as a standard, an author in whom Polybius himself detects so many errors.
I have spoken above of Eratosthenes' mistaken notion of the west and north of Europe.
But while we should excuse him and Dicaearchus who had never seen these districts, how can we excuse Polybius and Poseidonius?
Who but Polybius is it who calls the statement they make about distances in this case and in many others popular misstatements, but he is not even correct when he confutes them.
Walbank Commentary