CHAPTER 1 EUDOxUS OF CNIDUS Greek mathematician and astrono mer Eudoxus of Cnidus contributed to the identification of constellations and thus to the development of astronomy in ancient Greece He also established the first sophisticated model of planetary motion Eudoxus was born around 395 390 BCE in Cnidus Asia Minor now in Turkey He studied mathematics and medicine and later went to Athens where he took part in philosophical discussions at the famous Academy directed by the philosopher Plato He eventually returned to Cnidus where he became alegislator and continued his research until his death at age 53 In his astronomical works Eudoxus mapped out the constellations and described the phases of fixed stars the dates when they are visible He also discussed the sizes of the Sun Moon and Earth Perhaps Eudoxus s greatest fame stems from his being the first to create a geometric model of the motions of the Sun the Moon and I2
EUDOXUS OF CNIDUS the five planets known in ancient times His model consisted of a complex system of 27 interconnected spheres with Earth at the center One sphere held the fixed stars while each planet occupied four spheres and and had the Sun Moon three each Callippus and later Aristotle modified the model Aristotle's endorsement of its basic principles guaranteed an enduring interest through the Renaissance Most astronomers seem to have aban doned the astronomical views of Eudoxus by the middle of the 2nd century BCE Nevertheless his principle that every celestial motion is uniform and circular around the center endured until the time of the 17th century astronomer Johannes Kepler 13
GHAPTER 2 ARISTOTLE he ancient Greek philosopher Aristotle ranks among the greatest thinkers of all time His work in the natural and social sci ences greatly influenced virtually every area of modern thinking LIFE Aristotle was born in 384 BCE in Stagira on the northwest coast of the Aegean Sea His father was a friend and the physician of the king of Macedonia and the boy spent most of his childhood at the court At age 17 he went to Athens to study where he enrolled at Plato's Academy Plato was soon calling him the mind of the school Aristotle stayed at the Academy for 20 years leaving only when his beloved master died in 347 BCE In later years he renounced some of Plato's theories and went far beyond him in breadth of knowledge Aristotle became a teacher in a school on the coast of Asia Minor He spent two I4
ARISTOTLE years studying marine biology on Lesbos In 342 BCE Philip II invited Aristotle to return to the Macedonian court and teach his 13 year old son Alexander who was to become the world conqueror Alexander the Great After Alexander became king he gave Aristotle a large sum of money to set up a school in Athens Aristotle with a Bust of Homer a painting by Rembrandt Aristotle s view of the cosmos incorporated elements of earlier scientific and philosophical theories concerning the universe Photos com Thinkstock 15
