Thearidas wrote On Nature. Clement, Stromateis 5.133.1 (Stählin p. 416), quotes the Doric sentence: the beginning of beings — the beginning that is truly real — is one; for that, in the beginning, is one and only. It is printed in the Åbo collection of the Pythagorean texts of the Hellenistic period (1965), p. 201. The persona is dated to the third century BCE, not the seventh.
Clement cites him among the Pythagoreans who attest a first principle, a monad.
The fragment is that one-sentence ontology, not an archaic sage with no text.
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On the Physis of What Is
Ἀπόσπασμα
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