DiotimosReading Desk

Elements and matter

Density and rarefaction

πυκνόν; ἀραιόν; πύκνωσις; μάνωσις

puknon; araion; puknōsis; manōsis

The language of the dense and the rare describes differences in compactness.

From the book

Stobaeus, Volume I

John Stobaeus · Diotimos Editions · 2026

Browse this book’s lexicon →

Orientation

At a Glance

  • The wordThe language of the dense and the rare describes differences in compactness.
  • In StobaeusArchelaus’ report joins unlimited air to density and rarefaction, then names fire and water as the resulting alternatives.
  • In this editionThe edition preserves the report’s degree of explicitness.
  • A place to beginAir’s density and rarefaction explain opposed products.
English renderings
dense; rare; density; rarefaction

Meaning

The language of the dense and the rare describes differences in compactness. An account may explain transformations by changing the condition of a material rather than by introducing a wholly unrelated constituent.

Use in the book

Archelaus’ report joins unlimited air to density and rarefaction, then names fire and water as the resulting alternatives. Its compressed “one ... the other” does not explicitly match each condition with its product. The stars attributed to Parmenides and Heraclitus are described as condensations of fire and as nourished by exhalation.

Places to read

  1. I.10.12.7Air’s density and rarefaction explain opposed products.
  2. I.24.1iThe stars are condensations of fire nourished from below.
  3. I.27.4The dense and rarefied combine to produce a milk-like color.
  4. I.8.42bCondensation enters an explanation of winter.

Translation in this edition

The edition preserves the report’s degree of explicitness. “Condensation” is related physical vocabulary, but it should not erase the distinct wording of each passage.

Condensation

Puknōsis is a becoming dense or a state of increased density. In I.8.42b, the report attributed jointly to Empedocles and the Stoics links winter with air forced upward through condensation. “Condensation” here belongs to an ancient elemental explanation; it need not mean specifically the modern change from a gas to a liquid.

Rarefaction as thinning

Manōsis is rarefaction or thinning. The report about Archelaus at I.10.12.7 places it beside density in an account of unlimited air. The ensuing compressed statement names fire and water without explicitly matching each product to a condition. The familiar direction of such theories should not be used to rewrite what this particular report actually states.

Source note

Wachsmuth, volume I, printed pp. 107, 124, 203, 226. The lemma gives the descriptive pair; the reports also use nouns and verbs for becoming compact or rare.