Who was Aristotle?
May 2016 - Aristotle's father was Nicomachus, a doctor who lived near Macedon, in the north of Greece; his mother Phaestis was from Euboea. So, unlike Socrates and Plato, Aristotle was not originally from Athens. He was not from a rich family like Plato, though his father was not poor either.
Aristotle's father died when he was ten, and his mother probably soon afterwards. When Aristotle was seventeen, about 367 BC, he went to study at Plato's Academy. Plato was already pretty old then. Aristotle did very well at the Academy. But he never got to be among its leaders. When Plato died, Aristotle was almost forty, but Plato chose his own nephew Speusippus instead of Aristotle to lead the Academy. Probably Aristotle was pretty upset about being left out.
Soon afterwards, Aristotle left Athens and went to Macedon, where he may have been the tutor of the young prince Alexander, who grew up to be Alexander the Great. When Alexander grew up and became king, Aristotle went back to Athens and opened his own school there, the Lyceum (lie-SAY-um), in competition with Plato's Academy. Both schools were successful for hundreds of years.
Aristotle was more interested in science than Socrates or Plato, maybe because his father was a doctor. He wanted to use Socrates' logical methods to figure out how the real world worked; therefore Aristotle is really the father of today's scientific method. Aristotle may have been the first person to suggest (correctly) that the way your eyes worked was that light bounced off objects into your eyes; he figured this out by using a camera obscura - an early kind of camera invented in China, about fifty years before Aristotle used it. As Aristotle noticed, the bigger the box, the bigger the image will be. Experiments with the camera obscura convinced Aristotle that your eyes worked like the camera obscura - as indeed they do - and therefore that light entered your eyes to make the image, rather than rays coming out of your eyes to find objects (like bats using sonar) as many scientists thought.
Aristotle was especially interested in biology, in classifying plants and animals in a way that would make sense. This is part of the Greek impulse to make order out of chaos: to take the chaotic natural world and impose a man-made order on it.
When Alexander was traveling all over West Asia, he sent messengers to bring strange plants back to Aristotle for his studies (perhaps in some ways imitating the gardens of the Assyrian kings). Aristotle also tried to create order in peoples' governments. He created a classification system of monarchies, oligarchies, tyrannies, democracies and republics which we still use today.
When Alexander died in 323 BC, though, Demosthenes and other men led revolts against Macedonian rule in Athens. People accused Aristotle of being secretly on the side of the Macedonians (and maybe he was; he was certainly, like Plato, no democrat). He left town quickly (Theophrastus took over the Lyceum), and spent the last years of his life in Euboea, among his mother's family. Aristotle died of some sort of stomach problem when he was 62.
Learn by doing: find ten different kinds of plants outside and draw them
More about Greek philosophy
Aristotle: Philosopher and Scientist, by Margaret Anderson and Karen Stephenson (2004). For teens. Includes some suggested activities to help you understand the science.
Philosophy and Science in Ancient Greece: The Pursuit of Knowledge, by Don Nardo (2004). For teenagers. Don Nardo has written many books for young people about the ancient Greeks.
The Cambridge Companion to Greek and Roman Philosophy, edited by David Sedley (1997).