Pre-Socratic Philosophers

PRE-SOCRATIC PHILOSOPHERS
  Pre-Socratic philosophers were, as the name implies, Greek philosophers that came before the time of Socrates. There were several of these and each had their own set of beliefs and hypotheses. The primary thing that concerned them was substance, which involved defining what the world and things in it were made of, where these things came from and what ultimately became of them. In figuring this out they looked for practical, natural solutions, instead of trusting mythology as people had done previously.
The first of these philosophers was Thales, who has been referred to as the father of Greek philosophy. He has also been called the “Father of Science” since he was the first to develop hypotheses. It was his theory that everything that was in the world began with and consisted of water, which was necessary for life. He observed in nature that water could assume any shape. Other major accomplishments of his were in the field of mathematics, especially geometry. Because of this he is considered to be the first true mathematician.
Anaximander was a disciple of Thales and followed much of his teachings but had some theories of his own. He developed the first theory of evolution in that humans had evolved from fish. He departed from Thales’ teaching in that he did not believe that water alone could not be the sole element responsible for life. He introduced that the source of all things was an indefinite being, called an apeiron. This came about as the four elements (air, earth, water and fire) are formed and the way that they interact forms something like a primal chaos. He stated that the origin of the universe came from the separation of opposites in this and this “element” is the apeiron, from which everything comes from and also returns to when it dies. In this way apeirons are similar to atoms, the smallest building block of matter.
Anaximenes was a student of Anaximander and had his own theory in what things were made of. He...