Aristotle changed the world as he was the first to organize human knowledge into categories, some of which are still used in modern times. These categories include biology, mathematics and ethics.
Aristotle spent much of his time writing about the subjects he studied. He wrote 200 treaties on several subjects, although only 31 have survived. An example of one of his most famous treatises is "On the Soul." Here, he states the soul is the essence of any living thing. Aristotle determined that all living organisms have a soul. He believed that the body and the soul were one, and when the body died, so did the soul. Through his continued use of the scientific method, he altered many other fields of knowledge. By using this method, he became the first person to develop a system of reasoning. Aristotle was a student of Plato, although he disagreed with many of his theories. He was educated for 20 years at Plato's Academy in Athens, where he started at the age of 17. After Plato’s death, there was thought that he would take over Plato's Academy. However his disagreements with Plato were far too many. He branched off on his own and founded a school called the Lyceum.