Pyrrhos disciple Timon advanced some intellectual arguments which, from the standpoint of Greek logic, were very hard to answer. The only logic admitted by the Greeks was deductive, and all deduction had to start, like Euclid, from general principles regarded as self-evident. Timon denied the possibility of finding such principles. nothing can be proved. This argument, as we can see, cut at the root of the Aristotelian philosophy which dominated the Middle Ages.p. 234.

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