# Diogenes of Apollonia 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 Diogenes of Apollonia, a natural philosopher and pupil of Anaximenes, contemporary of Anaxagoras, who faced unpopularity and danger in Athens. His doctrines include air as the primary element, infinite worlds and void, generation and destruction from condensation and rarefaction, and a round earth fixed at the center of the universe.

## Themes in this chapter

### Natural Philosophy and Cosmology

Diogenes' doctrines center on air as the element, infinite worlds, void, and the generation of the cosmos through condensation and rarefaction.

## Character check-ins

### Diogenes of Apollonia

Native of Apollonia, son of Apollothemis, natural philosopher and pupil of Anaximenes, contemporary of Anaxagoras, unpopular at Athens.

### Anaximenes

Reported by Antisthenes as the teacher of Diogenes of Apollonia.

### Anaxagoras

Contemporary of Diogenes of Apollonia.

### Demetrius of Phalerum

Mentioned as the source in his Defense of Socrates for Diogenes' unpopularity and danger at Athens.

## Key lines

> It appears to me that he who begins any treatise ought to lay down principles about which there can be no dispute, and that his exposition of them ought to be simple and dignified.

Diogenes believed that any philosophical work should start with indisputable principles and be presented in a clear and dignified manner.

_Opening statement of Diogenes' treatise, emphasizing clarity and foundational certainty._

## Links

- HTML: https://www.betterreads.online/discover/the_lives_and_opinions_of_eminent_philosophers_se/chapters/diogenes-of-apollonia
- 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