**Going step by step, from ancient Greece to Europe via the east**

The Miletus school — Thales and his disciples Anaximander, Anaximenes — is considered to be the first at the beginning of the VI BC. It lasted for about a century and left behind astronomical observations, calendar, sundial, maps, the theorem on the equality of the angles of an isosceles triangle, and others. In the V century BС, Pythagoras and Heraclitus developed math and logic. Additionally, the Eleatic school has appeared, which was founded by Parmenides, and the widely known aporia about Achilles and a tortoise belongs to his successor Zeno of Elea. At the beginning of the IV BC, Democritus synthesized and developed the ideas of its predecessors. Next, the school of Plato has come, articles of his disciple Aristotle are concerned with physics and cosmology, so the strength, energy, potential, and movement in the sky are analyzed in there. In the III BC a great contribution to science has bee done by the Alexandrian school: Euclid, Archimedes and Aristarchus of Samos. In the next century, Claudius Ptolemy systematized knowledge in his Great Treatise, which in the Renaissance was known in Europe under the Arabic name Almagest.