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The Lives and Opinions of Eminent Philosophers · Chapter

Thales explained

This chapter introduces Thales of Miletus, often regarded as the first philosopher and one of the Seven Sages.

What happens

This chapter introduces Thales of Miletus, often regarded as the first philosopher and one of the Seven Sages. It covers his lineage, his pioneering work in astronomy and geometry, his political wisdom in advising Miletus against an alliance with Croesus, his ethical aphorisms, and his natural philosophy positing water as the fundamental principle. The chapter also discusses the varying accounts of his life, writings, and death, as well as the broader traditions surrounding the Seven Sages.

Themes in this chapter

  • Natural Philosophy and Cosmology

    Thales is presented as the first to study natural philosophy, asserting water as the principle of all things and attributing souls to lifeless objects.

  • Wisdom vs. Sophistry

    Thales is distinguished as the first to be called wise, and his practical aphorisms and political advice contrast with mere cleverness.

  • Virtue and Self-Sufficiency

    Thales' ethical sayings emphasize self-knowledge, moderation, and virtuous living, such as 'Know thyself' and avoiding reproach.

Characters to notice

  • Thales

    The central figure of the chapter, described as the first to be called wise, a founder of natural philosophy, astronomer, and political advisor.

  • Solon

    Mentioned as a fellow sage and correspondent of Thales, invited to Miletus.

  • Pherecydes of Syros

    Addressee of a letter from Thales, who expresses interest in studying under him.

  • Bias of Priene

    Mentioned as another sage who invited Solon to Priene.

  • Heraclitus

    Cited as one who confirms Thales' astronomical predictions.

  • Democritus

    Cited as a source for Thales' parentage and as confirming his astronomical work.

Key passages

  • He asserted water to be the principle of all things, and that the world had life and was full of daemons

    Thales believed that water was the fundamental substance underlying all existence, and that the universe was animate and inhabited by spiritual beings.

    Core tenet of Thales' natural philosophy.

  • When asked what was very difficult, he said, 'To know oneself.' And what was easy, 'To advise another.'

    Thales taught that self-knowledge is the hardest achievement, while giving advice to others is comparatively simple.

    Famous aphorism attributed to Thales, emphasizing introspection.

  • He was the first man to whom the name of Wise was given

    Thales was the first individual to be called a sage or wise man.

    Highlights Thales' foundational role in the tradition of Greek philosophy.