Presocratic philosophy, for all its diverse features, is united by the quest to understand the origin and nature of the world. The approach of the Pythagoreans to this quest is governed by their belief, probably based on studies of the numerical relations in musical harmony, that number or numerical structure plays a key role for explaining the world-order, the cosmos. It remains questionable to what extent the Pythagoreans, by positing number as an all-powerful explanatory concept, broke free from Presocratic ideas (...) that certain stuffs or material elements sufficed to account for the source and constitution of the world, but apparently number found such a universal application with them that Aristotle could summarize the Pythagorean position as ‘numbers…are the whole universe’ . Historians of Greek philosophy have generally accepted Aristotle's assessment. Of late, however, certain scholars have argued that the Pythagorean number doctrine is Aristotelian interpretation, unjustly foisted upon the Pythagoreans. Enlisted in support of their arguments are the fragments of Philolaus of Croton. Here we have the foremost representative of fifth-century Pythagoreanism, who states as his basic principles, not numbers exactly, but ‘limiters’ and ‘unlimiteds’, and who, it is argued, regards number solely as an epistemological aid for understanding the structure of reality. So Philolaus is called upon as a witness against Aristotle. The rationale goes something like this: Aristotle most likely had written sources for his knowledge of Pythagorean teachings; the only texts we know of with any certainty are Philolaus' book and the writings of Archytas; since Aristotle treats Archytas separately, he is mainly relying on Philolaus; because Philolaus does not expressly state that things are numbers, Aristotle's interpretation is wrong. (shrink)

A pergunta, “Tudo é número?” no título do famoso artigo de 1989 de Zhmud, deixa aberto um desafio para o extremamente importante testemunho aristotélico de que “tudo é número” era a definição fundamental da filosofia pitagórica. Tal desafio não é nada simples, especialmente quando se considera que, até então, as histórias tanto da filosofia quanto da matemática antiga parecem não ter dúvidas de que esta afirmação é correta. Este artigo pretende submeter à avaliação crítica a alegação de Aristóteles de que (...) os pitagóricos acreditavam que “tudo é número”. Nossa análise dos muitos modos nos quais Aristóteles enuncia a tese de que “tudo é número” revelará, para além de variações meramente semânticas, uma contradição teórica fundamental que o próprio Aristóteles parece incapaz de resolver. De fato, três versões diferentes da doutrina estão presentes na doxografia aristotélica: uma identificação dos números com objetos sensíveis; uma identificação dos princípios dos números com os princípios das coisas que existem; uma imitação dos objetos pelos números. Enquanto as versões e parecem identificar, em termos que lembram Platão, os números com a causa material da realidade, a versão, a saber, números como causas formais da realidade, é uma reconstrução aristotélica da teoria pitagórica. Aristóteles teria sido levado a tal reconstrução pela dificuldade que encontrou para aceitar a noção pitagórica material de número, e por considerá-la, para seu gosto, fortemente marcada pela recepção da mesma teoria no ambiente da Academia. (shrink)

We critically reconsider an old hypothesis of the role of the dekad in Pythagorean philosophy. Unlike Zhmud, we claim that: 1) the dekad did play a role in Philolaus’ astronomical system, and 2) Aristotle did not project Plato’s theory of the ten eidetic numbers onto the Pythagoreans. We claim that the dekad, as the τέλειος ἀριθμός, should be understood in Philolaus’ philosophy as completeness and the basis of counting in Greek – as in most other languages – in a decimal (...) system. Additionally, we argue that the number ten is not even a candidate for the τέλειος ἀριθμός in Plato’s philosophy. As a final result of our discussion, we compare and contrast Philolaus’, Plato’s, and Speusippus’ accounts of completeness in relation to numbers. (shrink)

In Doing What Comes Naturally, Stanley Fish argues on behalf of rhetoric and against philosophy. The latter assumes an independent reality that can be perceived without distortion and then reported in a transparent verbal medium. The former insists that this is impossible. As Fish acknowledges, this debate is a version of the old quarrel that has raged since the dialogues of Plato and the orations of the sophists. The present paper first examines how the Greek sophist Isocrates actually formulated the (...) terms of the debate. Then it turns to Plato in order to demonstrate that his treatment of the old quarrel is superior to Fish's postmodern update. (shrink)