Thales of Miletus: 640-546 BC
Thales of Miletus was the first man
to be given the title of philosopher, and was one of the first
known scientists. Since his writings did not survive, it is hard
to establish facts about his accomplishments. It was said that
he enabled the Lydian king Croesus' army to cross the Halys River by diverting
the flow of the water. He was also credited with predicting the
year of the eclipse of the sun of May 28, 585 BC. One of his most well known
ideas is that the earth floats on water, that all things come
from water, and that water is the basic substance of all things.
He came to this conclusion by noting that water is an element
of nutrition and survival to living things and that it was a common
element used in everyday life.
Anaxagoras: 500-428 BC
Anaxagoras was invited by Pericles to
come to Athens to teach new ideas of science and philosophy from
Anatolia. He described the cosmos as a continuous field in which
various qualities flow and mix together. He also believed that
other worlds existed and that they had men, houses, and canals
just as this one did. Many Athenian citizens did not appreciate this
kind of science because to them it was irreligious to suggest
that certain things, such as the Sun and Moon, are not gods, rather
only stones as Anaxagoras suggested. It also bothered the public
that he thought that the divine mind does not have a human body.
Later, when Pericles was no longer a favored citizen, Anaxagoras
was accused of impiety and fled Athens without standing trial.
Protagoras: 490-420 BC
Protagoras was one of the leading sophists.
A teacher of rhetoric and law, he taught students to argue both
sides of a case--introducing this method to legal training as
the "adversary system.". Protagoras was an excellent
and noted lawyer.
Gorgias of Leontini: 483-376 BC
Gorgias was a Greek sophist credited
with the earliest demonstration of a theory of aesthetics (appreciation)
and poetics. He was devoted to rhetoric as a means of determining
probability. Plato dedicated one of his dialogues, "Gorgias,"
to him and scholars have traced much of Aristotle's aesthetics
and poetics to Gorgias.
Socrates: 469-399 BC
While many Greek philosophers were concerned
mostly with the physical aspect of self or learning to satisfy
self-interest, Socrates contemplated what "self" really
was. Socrates spent much of his life
in conversation with Athenian citizens searching for knowledge
and truth. Oftentimes he exposed errors of those who claimed
to have wisdom. Following the Peloponnesian War, leaders of the
city were so irritated at him that they brought him to
trial for "impiety and corrupting the youth of Athens."
Though Socrates stood trial defending his beliefs, he was convicted
and executed by poisoning in 399 BC.
Democritus: 460-370 BC
Democritus developed the theory of atomism
which assumed a world made up of hard, indivisible particles of
matter moving through empty space. These atoms had shape, motion,
and mass, but no other qualities. Democritus explained the various
shapes and changes of atoms by referring to the transfer of
momentum as the atoms collide. Democritus believed in the unchanging
nature of the discernible universe and the changing nature of
the sensible universe. His ethical naturalism rejected any belief
that would deny man's responsibility for his own well-being. Rejecting
the belief in an afterlife, he believed that only man's conscience
could determine right or wrong actions.
Plato: 428-347 BC
Plato was a student of Socrates. The
Academy, where Plato
spent much of his life teaching, was founded by him in 387 BC
and was an institution devoted to research and instruction in
science and philosophy. Plato
was invited to Syracuse, in Sicily, to educate a new, young ruler, Dionysius
the Younger, in matters of philosophy and science. He wrote twenty-six
dialogues on philosophy and related ideas. His earliest dialogues
are said to be memorials to Socrates. The Euthyphro, the
Apology, and the Crito are
dialogues that follow Socrates through his trial and to his death.
The middle dialogues written by Plato came in the period after
the foundation of the Academy. These include the Republicwhich
questions justice and the Theaetetus which talks
about the nature of understanding. His later dialogues
were written after his return from Syracuse. Some of these are
the Sophist and the Statesman, which were written
about being and non-being, and the Timaeus, which discussed
the origin and nature of the universe. Plato
has been said to be among the most important and creative thinkers
of the ancient world.
Aristotle: 384-322 BC
Aristotle
studied under Plato. In 343 BC he tutored Alexander the Great
(age 13 at the time) for three years. This tutoring did not, however,
have much effect on Alexander's thoughts and actions. Alexander
later subsidized Aristotle's
research in natural sciences. While studying the natural sciences,
he directed research in botany and zoology. Aristotle
founded the Lyceum, the second of the four great schools, and he
developed one of the greatest libraries in the Greek world. He
maintained the combined roles of encyclopedist, scientist, and
philosopher. It has been said that he wrote over 400 literary
works. After being accused of dangerous teachings and being exiled,
he died at Chalcis on the island of Euboea.
Epicurus: 341-270 BC
Epicurus developed the school of thought
known as Epicureanism, which deals with ideas concerning pleasure,
during the decline of ancient Greece. At the time, Epicureanism
was relief from increasing social disorganization. His ideas were
distinguished for having had constancy and doctrine. After Alexander's
death he went to Asia Minor to teach and moved back to Athens
in 306 BC. He developed and taught in the Garden of Epicurus which
was known as a sanctuary from turmoil of the outer world. The
Garden ranked as one of the great schools of antiquity, along
with Plato's Academy, Aristotle's Lyceum, and Zeno's Stoa. There
are very few letters and writings from Epicurus,
since most have been lost over the years. The writings that have
been found include a summary of his theories of physics and astronomy,
theory of knowledge, and his ethics.
