The central importance of the ancient Greek Philosopher Socrates can be seen by the fact
philosophers before him are called “Presocratics” and the two major philosophers after him,
Plato and Aristotle, concern themselves with many of the issues that he discusses. The
Presocratics not only studied questions of human knowledge and ethics, but also ones about
the physical world. We do not have the complete works of any of the Presocratics and have to
rely on partial quotations by later writers.
The first Presocratic was Thales who lived in Ionia, a Greek colony on the coast of Asia Minor,
present-day Turkey, around the beginning of the 6th century B.C. He is best known for his
statement “all things are water”. While this seems strange, even comical, to us, it shows a desire
to understand the universe not in terms of divine beings, but in terms of a single, underlying
physical principle.
The next Presocratic was Anaximander, a little younger than Thales. He suggested a first
principle far more abstract than water: the indefinite or unlimited, one might even say, the
infinite.
Following is Xenophanes, who wrote in poetry. He was skeptical of traditional religious ideas,
writing that if animals could write they would make their gods resembling themselves. He concludes that there is one god in no way similar to people in body or thought.
Next comes Heraclitus towards the end of the 6th century. His most famous saying is
“everything flows”. By this he means that the only constant is change. Another of his sayings
is: “no one can step into the same river twice”, since it is always moving and changing. Unlike
Thales, Heraclitus takes fire to be the basic element of the universe.
Exactly opposed to Heraclitus is Parmenides. He wrote his philosophy in a poem that we have
much but not all of. The poem is an allegory about being shown the way of truth by a goddess.
T
The true path leads to the knowledge that reality is a giant unmoving sphere. This may seem
weird, but he discusses the concept of being and not-being in terms of this. The false path is the
one of seeming where the world appears to have various forms.
The most famous Presocratic is Pythagoras, a little earlier than Parmenides. His discovery
about the relationship of the two shorter sides in a right triangle to the longest one has brought
him everlasting fame. His school was also concerned with the mathematics of music and
believed that number is the key to the universe, much as physicists nowadays believe.
There are other Presocratics, but I will leave them out for now. This is enough to give you some
idea of Greek philosophical thought before Socrates. The scene now focuses on the city of
Athens in the 5th Century. Greece had just successfully pushed back an invasion by the
Persians and was undergoing a period of great prosperity. During this century there was an
unbelievable flowering of achievement in almost all aspects of culture and most of the forms of
literature, as well as art, architecture and government developed. It is truly called a Golden Age.
However, prosperity is not always one-sided and can bring with it troubling aspects. One of
these was the so-called Sophistic movement. You might think from the name that this was a
good thing since the Greek word “sophos” means wise. However, the ending “-istic” here means
resembling or pretending. In fact the Sophists were more interested in oratory than seeking
truth. In fact, they claimed to be able to teach how to make the worse argument win out over the
better, somewhat as a lawyer might do. Socrates emerged in this environment as someone who
was genuinely interested in truth, but challenged conventional notions in doing so. A famous
type of dialogue that he might have would go like this: I know what a good carpenter is like and
what a good law is, but who can tell me what the nature of goodness itself is? This was very
difficult to respond to. On top of presenting this problem, Socrates would state that the only thing
he knew was that he did not know. Some people took this as mockery and the same thing as
the sophists were practicing. When he drew a following among the youth of Athens, he was put
on trial for corrupting them with his teachings. Socrates might have been able to convince the
court of his innocence by downplaying certain aspects of his behavior. However, he gave a
speech called “The Apology”, which means defense, that only made things worse. He was
found guilty and sentenced to death. Even in prison, his friends offered him a way to escape,
which he refused, thinking that would go against his beliefs.
“The Apology” is the earliest of the dialogues of Socrates written down by his student Plato. It is
not really a dialogue but a monologue and most likely is the closest of all of Plato’s writings to
Socrates’ actual words. Plato goes on to write many other dialogues in which Socrates discusses various other subjects. However, a theme common to almost of all of these is how to define
abstract concepts like “the good”. Plato’s dialogues are usually divided into early, middle and
late periods and tend to get further away from Socrates’ actual words and more towards
expressing Plato’s own thoughts. One of the most famous of these dialogues comes from the
Middle Period, in which Plato describes his concept of the ideal state. This is “The Republic”.
In the late dialogues Plato comes up with the “theory of forms” which is his own answer to
Socrates’ questions. Roughly speaking, it is what we would think of as abstract ideas as
opposed to particulars. This is an issue that persists in philosophy to this day. Interestingly,
the dialogue that Plato presents the theory of forms most decisively is called the “Parmenides”,
where the Presocratic of that name has a discussion with his pupil Socrates.
The last great figure is Aristotle. He was a student of Plato’s and the teacher of Alexander
the Great, near the end of the 5th century. We have very many writings of Aristotle. Their
style is far from Plato’s polished literary one. In fact, they most likely are lecture notes, either
written by Aristotle himself or his students and can be dry reading. They cover a wide range of
topics: ethics, literary criticism, biology, physics etc. All of these have been very influential,
although some, especially his notions of physics are now only of historical interest. However,
there is one group of five works called The Organon or Instrument, where Aristotle creates
almost de novo the subject of logic. These are among his most challenging works and still
are relevant in philosophy. In these works, but also others, Aristotle discusses the ideas of some
of his predecessors, such as Plato and his theory of forms. Many of the quotations from
the Presocratics are preserved by Aristotle, which otherwise would have been lost entirely.