Democritus

c. 460 - c. 370 BCE · Greek (Ionian, of Abdera in Thrace) · Presocratic atomist physics, cosmology, epistemology, ethics

By convention sweet, by convention bitter; but in reality atoms and void.

Democritus traveled further than almost any philosopher of antiquity — Egypt, Persia, possibly India — yet is remembered for saying he visited Athens and no one recognized him. He worked from Abdera, a small Thracian city, with his teacher Leucippus, on a question that would define two millennia of argument: what is the world made of?

Topics Democritus addresses

• atoms and void
• atoms as indivisible and eternal
• the void as what is not
• infinite variety of atomic shapes and sizes
• the nomos/physis distinction
• by convention sweet, by convention bitter
• secondary qualities as conventional
• primary atomic properties
• genuine vs bastard knowledge
• the wretched mind dialogue
• truth is in the depths
• the eidola theory of sensation
• euthymia
• cheerful self-sufficiency
• the cosmic swirl
• innumerable worlds
• mechanical cosmogony
• necessity and chance
• nothing happens in vain
• anti-teleology
• the atomic theory of soul
• response to Parmenidean monism
• the joint Leucippus-Democritus project
• anti-creationism

Questions to put to Democritus

Atoms and Void — The Fundamental Ontology

• What do you mean when you say the only things that exist are atoms and void?
• How can atoms be indivisible if everything else is divisible?
• What's the difference between an atom's shape and the conventional qualities like sweetness or color?
• How does the void exist if it's literally nothing?
• Were you responding to Parmenides when you developed atomism, or is that just one context for the doctrine?

By Convention Sweet, By Convention Bitter

• What do you mean by 'by convention sweet, by convention bitter; but in reality atoms and void'?
• If color and taste aren't real properties of things, what are they?
• How do the films streaming from objects produce sensations in us?
• Why should I believe that the atomic reality is more real than what I directly experience?
• What's the difference between primary properties like shape and secondary qualities like sweetness?

Necessity, Chance, and the Cosmic Swirl

• How does the cosmic swirl of atoms produce ordered worlds without any designer?
• What do you mean when you say nothing happens in vain but everything from reason and by necessity?
• How is your view different from saying everything just happens randomly?
• Why do you reject the idea that nature has purposes or goals?
• How do you respond to Aristotle's charge that atomism is necessity without adequate explanation?

Genuine and Bastard Knowledge

• What's the difference between genuine knowledge and bastard knowledge?
• How can reason give us genuine knowledge if all our evidence comes from the senses?
• What do you mean when you say 'truth is in the depths'?
• Can you explain the wretched mind dialogue where the senses challenge the mind?
• Are you saying we can never really know the atomic reality, or just that it's difficult?

Euthymia and the Atomic Soul

• What is euthymia and why does it matter so much to you?
• How is the soul made of atoms if it can think and feel?
• What's the connection between the atomic structure of the soul and cheerfulness?
• Why do you think we should derive our joys from ourselves rather than from fortune?
• How does understanding that the soul is atoms help me live better?

Converse with Democritus on Simposeum. Replies are grounded in the surviving fragments and reports of Democritus, cited to the page.