---
title: "Science in classical antiquity"
chunk: 2/6
source: "https://en.wikipedia.org/wiki/Science_in_classical_antiquity"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T03:38:50.555898+00:00"
instance: "kb-cron"
---

The earliest Greek philosophers, known as the pre-Socratics, were materialists who provided alternative answers to the same question found in the myths of their neighbors: "How did the ordered cosmos in which we live come to be?" Although the question is much the same, their answers and their attitude towards the answers is markedly different. As reported by such later writers as Aristotle, their explanations tended to center on the material source of things.
Thales of Miletus (624–546 BC) considered that all things came to be from and find their sustenance in water.  Anaximander (610–546 BC) then suggested that things could not come from a specific substance like water, but rather from something he called the "boundless". Exactly what he meant is uncertain but it has been suggested that it was boundless in its quantity, so that creation would not fail; in its qualities, so that it would not be overpowered by its contrary; in time, as it has no beginning or end; and in space, as it encompasses all things.  Anaximenes (585–525 BC) returned to a concrete material substance, air, which could be altered by rarefaction and condensation.  He adduced common observations (the wine stealer) to demonstrate that air was a substance and a simple experiment (breathing on one's hand) to show that it could be altered by rarefaction and condensation.
Heraclitus of Ephesus (about 535–475 BC), then maintained that change, rather than any substance was fundamental, although the element fire seemed to play a central role in this process.  Finally, Empedocles of Acragas (490–430 BC), seems to have combined the views of his predecessors, asserting that there are four elements (Earth, Water, Air and Fire) which produce change by mixing and separating under the influence of two opposing "forces" that he called Love and Strife.
All these theories imply that matter is a continuous substance.  Two Greek philosophers, Leucippus (first half of the 5th century BC) and Democritus came up with the notion that there were two real entities: atoms, which were small indivisible particles of matter, and the void, which was the empty space in which matter was located.  Although all the explanations from Thales to Democritus involve matter, what is more important is the fact that these rival explanations suggest an ongoing process of debate in which alternate theories were put forth and criticized.
Xenophanes of Colophon prefigured paleontology and geology as he thought that periodically the earth and sea mix and turn all to mud, citing several fossils of sea creatures that he had seen.

==== Pythagorean philosophy ====

The materialist explanations of the origins of the cosmos were attempts at answering the question of how an organized universe came to be; however, the idea of a random assemblage of elements (e.g., fire or water) producing an ordered universe without the existence of some ordering principle remained problematic to some.
One answer to this problem was advanced by the followers of Pythagoras (c. 582–507 BC), who saw number as the fundamental unchanging entity underlying all the structure of the universe. Although it is difficult to separate fact from legend, it appears that some Pythagoreans believed matter to be made up of ordered arrangements of points according to geometrical principles: triangles, squares, rectangles, or other figures. Other Pythagoreans saw the universe arranged on the basis of numbers, ratios, and proportions, much like musical scales. Philolaus, for instance, held that there were ten heavenly bodies because the sum of 1 + 2 + 3 + 4 gives the perfect number 10. Thus, the Pythagoreans were some of the first to apply mathematical principles to explain the rational basis of an orderly universe—an idea that was to have immense consequences in the development of scientific thought.

==== Hippocrates and the Hippocratic Corpus ====
According to tradition, the physician Hippocrates of Kos (460–370 BC) is considered the "father of medicine" because he was the first to make use of prognosis and clinical observation, to categorize diseases, and to formulate the ideas behind humoral theory. However, most of the Hippocratic Corpus—a collection of medical theories, practices, and diagnoses—was often attributed to Hippocrates with very little justification, thus making it difficult to know what Hippocrates actually thought, wrote, and did.
Despite their wide variability in terms of style and method, the writings of the Hippocratic Corpus had a significant influence on the medical practice of Islamic and Western medicine for more than a thousand years.

=== Schools of philosophy ===

==== The Academy ====