# Thales explained — The Lives and Opinions of Eminent Philosophers

> Chapter companion for The Lives and Opinions of Eminent Philosophers by Diogenes Laërtius.

## 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.

## Character check-ins

### 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 lines

> 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._

## Links

- HTML: https://www.betterreads.online/discover/the_lives_and_opinions_of_eminent_philosophers_se/chapters/thales
- Book: https://www.betterreads.online/discover/the_lives_and_opinions_of_eminent_philosophers_se
- All chapters: https://www.betterreads.online/discover/the_lives_and_opinions_of_eminent_philosophers_se/chapters