PRESOCRATIC PHILOSOPHERSThales (624-546 BC) is probably the first to use scientific reasoning to explain nature. Mathematician, astronomer, engineer, meteorologist. Established theoretical Geometry with Theorems and proofs, measured the height of the pyramids with the theory of similar triangles that he developed, founder of exact science. Predicted a solar eclipse, understood that the Earth is spherical, the stars are made of substances similar to the ones of the Earth, started electricity (studying ambers attraction to bodies when rubbed and charged).

Pythagoras of Samos, Greece (570-500 BC), proves the Pythagorean theorem and pursues a theoretical systematic study of numbers. He introduces the notion that the Universe and everything in Nature has to be described accurately with mathematics and numbers, that are the essence of nature.He invents the Multiplication table. Pythagoras studies theoretically the relations of integer numbers, odd and even numbers. He introduces the Geometrical representation of numbers.He proves that the sum of the three angles of a triangle equals 180 degrees. He establishes Music as a discipline. He performs the first experiments in physics with measurements and discovers the relation between the length of a chord and the tone it gives.He introduces the Evolution of the Universe from an initial nucleus that expands, like the Big Bang.He believes in the Immortality of the soul.He established a Philosophical School in southern Italy, that was called Greater Greece, at that time.Heraclitus (6th-5th CBC) tries to understand tha nature of Cosmos. Matter is made of four elements: fire, air, water, earth. All substances come from these simple bodies that he terms elements. Introduced dialectics, causality, humans are responsible for their fate.Everything changes continuously. NATIONAL AND KAPODISTRIAN UNIVERSITY OF ATHENSAnaxagoras (500/488-428 BC) understands that celestial bodies are not gods but made of matter. Matter can be divided continuously to small particles. He comes to Athens from Ionia and establishes a very important Philosophical School (University). This changes drastically the course of Philosophy, as he puts the seeds of philosophy in Athens.His most important pupil was Pericles who changes completely Athens to a very important city state with Acropolis and the Parthenon.Anaxagoras School in Athens puts the foundations to the Academy of Plato and Lyceum of Aristotle that established Philosophy as we know it.Anaximander (610-545 BC) Introduced the term Principle, constructed the first map of the Earth, solar accurate clocks, introduced the first theory of evolution of species, life comes from the water, where some worms developed first, humans come from a kind of shark that has fetus similar to human. Measured the change of the inclination of solar altitude during the year (solstices, equinoxes) Anaximenes (585-525 BC) Introduced a mechanical model for the Universe. Introduced measurements in the study of phenomena. Defines stars and planets a different celestial objects. The Moon is illuminated from the Sun. He gives the explanation of eclipses and introduces the cycle of water (evaporation, clouds, rain, snow, rainbow).

Thanks to

The Alexandros S. Onasis Foundationthe John F. Costopoulos FoundationLeverhulme Trust,University of AthensNational Archaeological Museum, Athens, GreeceProf. J H Seiradakis, Prof M. Edmunds, Dr T. Freeth, Mr Y Bitsakis, Dr H. Magkou, Mrs M. ZafeiropoulouX-tek Systems, HP, Dr R. Hadland, Dr T Malzbender, Dr A. Tselikas, Dr C. Kritzas, Mr D. Kriaris, Prof M. Roumeliotis, Dr F. Vafea, Prof M. Papathanassiou, Dr. G. Hensiksson, Mrs L. Mandaliou-Stadiati-Lykopanti, Costas and George PapouliasHubble Space Telescope

Copyright University of Athens 2011Information: Xenophon Moussas Xmoussas@phys.uoa.gr

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