Jette+.Ancient+Times+(450+ADand+years+prior)

= Ancient Times =

450AD and years prior = = = = = = = Empedocles c.450 BC =

“Happy is he who has gained the wealth of divine thoughts, wretched is he whose beliefs about the gods are dark.”
  **The four elements: c.450 BC** Bio:


 * Empedocles was born in Acragas on the south coast of Sicily.
 * Empedocles was born into a rich aristocratic family. He traveled throughout the Greek world participating fully in the extraordinary desire for learning and understanding which gripped that part of the world.

Discoveries:


 * He is best known for his belief that all matter was composed of four elements: fire, air, water, and earth.
 * Empedocles did not base his four element hypothesis on any experimental evidence.
 * Empedocles believed that light traveled with a finite velocity, not through any experimental evidence, of course, but simply through reasoning.
 * Several of Empedocles' ideas have turned out to be correct. In addition to his belief in the finite velocity of light he also developed a crude evolutionary theory based on the survival of the fittest. He also had a form of the law of conservation of energy and had a theory of constant proportions in chemical reactions.

= Democritus c. 460-370 BC = = "Nothing exists except atoms and empty space; everything else is opinion."  = =**Democritus** 460 BC – 370 BC Bio: =

Discoveries:
 * Democritus was an Ancient Greek philosopher born in Abdera, Thrace, Greece. He was an influential pre-Socratic philosopher and pupil of Leucippus, who formulated an atomic theory for the cosmos.
 * His exact contributions are difficult to disentangle from his mentor Leucippus, as they are often mentioned together in texts. Their speculation on atoms, taken from Leucippus, bears a passing and partial resemblance to the nineteenth-century understanding of atomic structure that has led some to regard Democritus as more of a scientist than other Greek philosophers; nevertheless their ideas rested on very different bases.
 * Largely ignored in Athens, Democritus was nevertheless well-known to his fellow northern-born philosopher Aristotle. Plato is said to have disliked him so much that he wished all his books burned.
 * Democritus was also a pioneer of mathematics and geometry in particular. We only know this through citations of his works (titled //On Numbers//, //On Geometrics//, //On Tangencies//, //On Mapping//, and //On Irrationals//) in other writings, since most of Democritus' body of work did not survive the Middle Ages.


 * In the late 5th century BC Democritus sets out an interesting theory of elemental physics.
 * He states that all matter is composed of eternal, indivisible, indestructible and infinitely small substances which cling together in different combinations to form the objects perceptible to us.
 * The Greek word for indivisible is //atomos//. Democritus theory gives birth to the atom.
 * The theory of Democritus and Leucippus held that everything is composed of "atoms", which are physically, but not geometrically, indivisible; that between atoms lies empty space; that atoms are indestructible; have always been, and always will be, in motion; that there are an infinite number of atoms, and kinds of atoms, which differ in shape, and size. Of the mass of atoms, Democritus said "The more any indivisible exceeds, the heavier it is." But their exact position on weight of atoms is disputed.

= Aristotle c.384-322 BC =

"Good habits formed at youth make all the difference"
 **Aristotle** 384 BC – 322 BC Bio:

Discoveries:
 * **Aristotle** was a Greek philosopher, a student of Plato and teacher of Alexander the Great.
 * His writings cover many subjects, including physics, metaphysics, poetry, theater, music, logic, rhetoric, politics, government, ethics, biology, and zoology.
 * Together with Plato and Socrates (Plato's teacher), Aristotle is one of the most important founding figures in Western philosophy. Aristotle's writings were the first to create a comprehensive system of Western philosophy, encompassing morality and aesthetics, logic and science, politics and metaphysics.
 * Upon Alexander's death, anti-Macedonian sentiment in Athens once again flared. Eurymedon the hierophant denounced Aristotle for not holding the gods in honor. Aristotle fled the city to his mother's family estate in Chalcis, explaining, "I will not allow the Athenians to sin twice against philosophy," a reference to Athens's prior trial and execution of Socrates. However, he died in Euboea of natural causes within the year.


 * Aristotle, practical as ever in his determination to get things worked out in detail, proposed a new theory to explain how the four elements of Empedocles and the atoms of Democritus produce the wide range of substances apprehended by our senses
 * He suggests that there are two pairs of alternatives - hot and cold, moist and dry - which provide the exact nature of matter. In broad terms the four possible combinations are the four elements: earth (cold and dry), air (hot and moist), fire (hot and dry), water (cold and moist). But it is the infinitely variable balance between these qualities which creates the different atoms of stone or wood, bone or flesh.
 * Aristotle is credited with the earliest study of formal logic, and his conception of it was the dominant form of Western logic until 19th century advances in mathematical logic
 * Aristotle's atomic theory differed because he believed that a fifth element, aether, existed and made up all the heavenly bodies and spheres (i.e. stars and planets). He had no access to the modern technology available today, and was working off of hundreds of years of accepted theory based around the four classical elements.

Works Cited For This Page  http://www-history.mcs.st-andrews.ac.uk/Biographies/Empedocles.html http://en.wikipedia.org/wiki/Democrituswww.brainyquote.comhttp://en.wikipedia.org/wiki/Aristotle http://www.ucmp.berkeley.edu/history/aristotle.html http://www.humanistictexts.org/democritus.htm

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