Aristotle was born in 384 BC and lived until 322 BC. He was a Greek philosopher and scientist, who shares with Plato being considered the most famous of ancient philosophers. He was born at Stagira, in Macedonia, the son of a physician to the royal court. When he was 17, he went to Athens to study at Plato's Academy. He stayed for about 20 years, as a student and then as a teacher.

When Plato died in 347 BC, Aristotle moved to Assos, a city in Asia Minor, where a friend of his named Hermias was the ruler. He counseled Hermias and married his niece and adopted daughter, Pythias (wierd names, huh). After Hermias was captured and executed by the Persians, Aristotle went to Pella, Macedonia's capital, and became the tutor of the king's young son Alexander, later known as Alexander the Great. In 335, when Alexander became king, Aristotle went back to Athens and established his own school, the Lyceum.Since a lot of the lessons happened when teachers and students were walking, it was nicknamed the Peripatetic school (Peripatetic means walking). When Alexander died in 323 BC, strong anti-Macedonian feeling was felt in Athens, and Aristotle went to a family estate in Euboea. He died there the following year.

Aristotle, like Plato, used his dialogue in his beginning years at the Academy. Apart from a few fragments in the works of later writers, his dialogues have been wholly lost. Aristotle also wrote some short technical writings, including a dictionary of philosophic terms and a summary of the "doctrines of Pythagoras" (the guy from the Pythagorean Theorem). Of these, only a few short pieces have survived. Still in good shape, though, are Aristotle's lecture notes for carefully outlined courses treating almost every type of knowledge and art. The writings that made him famous are mostly these, which were collected by other editors.

Among the writings are short informative lectures on logic, called Organon (which means "instrument"), because "they provide the means by which positive knowledge is to be attained"(They're not my words, I'm quoting him). His writing on natural science include Physics, which gives a huge amount of information on astronomy, meteorology, plants, and animals. His writings on the nature, scope, and properties of being, (I know what one of them means!) which Aristotle called First Philosophy (to him it was "Prote philosophia"), were given the title Metaphysics in the first published version of his works (around 60 BC), because in that edition they followed Physics. His belief of the "Prime Mover", or first cause, was pure intellect, perfect in unity,immutable, and, as he said, "the thought of thought," is given in the Metaphysics. Other famous works include his Rhetoric, his Poetics (which we only have incomplete pieces of), and his Politics (also incomplete).

Because of the influence of his father's medical profession, Aristotle's philosophy was mainly stressed on biology, the opposite of Plato's emphasis on mathematics. Aristotle regarded the world as "made up of individuals (substances) occurring in fixed natural kinds (species)" (more confusing quotes, yippey!). He said "each individual has its built-in specific pattern of development and grows toward proper self-realization as a specimen of its type. Growth, purpose, and direction are thus built into nature." Although science studies many things, according to Aristotle, "these things find their existence in particular individuals. Science and philosophy must therefore balance, not simply choose between, the claims of empiricism (observation and sense experience) and formalism (rational deduction)."

One of the most famous of Aristotle's contributions was a new notion of causality. "Each thing or event," he thought, "has more than one 'reason' that helps to explain what, why, and where it is." Earlier Greek thinkers thought that only one sort of cause can explain itself; Aristotle said four.(The word Aristotle uses, aition, "a responsible, explanatory factor" is not the same as the word cause now.)

These four causes are the "material cause", (the matter out of which a thing is made); the "efficient cause", (the source of motion, generation, or change); the "formal cause", (the species, kind, or type); and "the final cause", (the goal, or full development, of an individual, or the intended function of a construction or invention.) Although I don't know what these mean, they sound philosophical. An example he gave is "a young lion is made up of tissues and organs, its material cause; the efficient cause is its parents, who generated it; the