Plato
Born: 427 BC in Athens, Greece
Died: 347 BC in Athens, Greece
Before giving details of Plato's life we will
take a few moments to discuss how definite the details are
which we give below. The details are mostly given by Plato
himself in letters which seem, on the face of it, to make
them certain. However, it is disputed whether Plato did indeed
write the letters so there are three possible interpretations.
Firstly that Plato wrote the letters and therefore the details
are accurate. Secondly that although not written by Plato,
the letters were written by someone who knew him or at least
had access to accurate information on his life. The third
possibility, which unfortunately cannot be ruled out, is that
they were written by someone as pure fiction.
Next
we should comment on the name 'Plato'. Rowe writes:-
It was claimed that Plato's real name was
Aristocles, and that 'Plato' was a nickname (roughly 'the
broad') derived either from the width of his shoulders, the
results of training for wrestling, or from the breadth of
his style, or from the size of his forehead.
Plato was the youngest son of Ariston and
Perictione who both came from famous wealthy families who
had lived in Athens for generations. While Plato was a young
man his father died and his mother remarried, her second husband
being Pyrilampes. It was mostly in Pyrilampes' house that
Plato was brought up. Aristotle writes that when Plato was
a young man he studied under Cratylus who was a student of
Heracleitus, famed for his cosmology which is based on fire
being the basic material of the universe. It almost certain
that Plato became friends with Socrates when he was young,
for Plato's mother's brother Charmides was a close friend
of Socrates.
The Peloponnesian War was fought between Athens
and Sparta between 431 BC and 404 BC. Plato was in military
service from 409 BC to 404 BC but at this time he wanted a
political career rather than a military one. At the end of
the war he joined the oligarchy of the Thirty Tyrants in Athens
set up in 404 BC, one of whose leaders being his mother's
brother Charmides, but their violent acts meant that Plato
quickly left.
In 403 BC there was a restoration of democracy
at Athens and Plato had great hopes that he would be able
to enter politics again. However, the excesses of Athenian
political life seem to have persuaded him to give up political
ambitions. In particular, the execution of Socrates in 399
BC had a profound effect on him and he decided that he would
have nothing further to do with politics in Athens.
Plato
left Athens after Socrates had been executed and travelled
in Egypt, Sicily and Italy. In Egypt he learnt of a water
clock and later introduced it into Greece. In Italy he learned
of the work of Pythagoras and came to appreciate the value
of mathematics. This was an event of great importance since
from the ideas Plato gained from the disciples of Pythagoras,
he formed his idea:-
... that the reality which scientific thought
is seeking must be expressible in mathematical terms, mathematics
being the most precise and definite kind of thinking of which
we are capable. The significance of this idea for the development
of science from the first beginnings to the present day has
been immense.
Again there was a period of war and again
Plato entered military service. It was claimed by later writers
on Plato's life that he was decorated for bravery in battle
during this period of his life. It is also thought that he
began to write his dialogues at this time.
On his return to Athens Plato founded, in
about 387 BC, on land which had belonged to Academos, a school
of learning which being situated in the grove of Academos
was called the Academy. Plato presided over his Academy in
Athens, an institution devoted to research and instruction
in philosophy and the sciences, from 387 BC until his death.
His reasons for setting up the Academy were connected with
his earlier ventures into politics. He had been bitterly disappointed
with the standards displayed by those in public office and
he hoped to train, in his Academy, young men who would become
statesmen. However, having given them the values that Plato
believed in, Plato thought that these men would be able to
improve the political leadership of the cities of Greece.
Only two further episodes in Plato's life
are recorded. He went to Syracuse in 367 BC following the
death of Dionysius I who had ruled the city. Dion, the brother-in-law
of Dionysius I, persuaded Plato to come to Syracuse to tutor
Dionysius II, the new ruler. Plato did not expect the plan
to succeed but because both Dion and Archytas of Tarentum
believed in the plan then Plato agreed. Their plan was that
if Dionysius II was trained in science and philosophy he would
be able to prevent Carthage invading Sicily. However, Dionysius
II was jealous of Dion who he forced out of Syracuse and the
plan, as Plato had expected, fell apart.
Plato returned to Athens, but visited Syracuse
again in 361 BC hoping to be able to bring the rivals together.
He remained in Syracuse for part of 360 BC but did not achieve
a political solution to the rivalry. Dion attacked Syracuse
in a coup in 357, gained control, but was murdered in 354.
Field
writes that Plato's life:-
... makes it clear that the popular conception
of Plato as an aloof unworldly scholar, spinning theories
in his study remote from practical life, is singularly wide
of the mark. On the contrary, he was a man of the world, an
experienced soldier, widely travelled, with close contacts
with many of the leading men of affairs, both in his own city
and elsewhere.
Plato's
main contributions are in philosophy, mathematics and science.
However, it is not as easy as one might expect to discover
Plato's philosophical views. The reason for this is that Plato
wrote no systematic treatise giving his views, rather he wrote
a number of dialogues (about 30) which are written in the
form of conversations. Firstly we should comment on what superb
pieces of literature these dialogues are:-
They show the mastery of language, the power
of indicating character, the sense of a situation, and the
keen eye for both its tragic and its comic aspects, which
set Plato among the greatest writers of the world. He uses
these gifts to the full in inculcating the lessons he wants
to teach.
In letters written by Plato he makes it clear
that he understands that it will be difficult to work out
his philosophical theory from the dialogues but he claims
that the reader will only understand it after long thought,
discussion and questioning. The dialogues do not contain Plato
as a character so he does not declare that anything asserted
in them are his own views. The characters are historic with
Socrates usually the protagonist so it is not clear how much
these characters express views with which they themselves
would have put forward. It is thought that, at least in the
early dialogues, the character of Socrates expresses views
that Socrates actually held.
Through these dialogues, Plato contributed
to the theory of art, in particular dance, music, poetry,
architecture, and drama. He discussed a whole range of philosophical
topics including ethics, metaphysics where topics such as
immortality, man, mind, and Realism are discussed.
He discussed the philosophy of mathematics,
political philosophy where topics such as censorship are discussed,
and religious philosophy where topics such as atheism, dualism
and pantheism are considered. In discussing epistemology he
looked at ideas such as a priori knowledge and Rationalism.
In his theory of Forms, Plato rejected the changeable, deceptive
world that we are aware of through our senses proposing instead
his world of ideas which were constant and true.
Let
us illustrate Plato's theory of Forms with one of his mathematical
examples. Plato considers mathematical objects as perfect
forms. For example a line is an object having length but no
breadth. No matter how thin we make a line in the world of
our senses, it will not be this perfect mathematical form,
for it will always have breadth. In the Phaedo Plato talks
of objects in the real world trying to be like their perfect
forms. By this he is thinking of thinner and thinner lines
which are tending in the limit to the mathematical concept
of a line but, of course, never reaching it. Another example
from the Phaedo is given :-
The instance taken there is the mathemtical
relation of equality, and the contrast is drawn between the
absolute equality we think of in mathematics and the rough,
approximate equality which is what we have to be content with
in dealing with objects with our senses.
Again in the Republic Plato talks of geometrical
diagrams as imperfect imitations of the perfect mathematical
objects which they represent.
Plato's contributions to the theories of education
are shown by the way that he ran the Academy and his idea
of what constitutes an educated person. He also contributed
to logic and legal philosophy, including rhetoric.
Although Plato made no important mathematical
discoveries himself, his belief that mathematics provides
the finest training for the mind was extremely important in
the development of the subject. Over the door of the Academy
was written:-
Let no one unversed in geometry enter here.
Plato
concentrated on the idea of 'proof' and insisted on accurate
definitions and clear hypotheses. This laid the foundations
for Euclid's systematic approach to mathematics. In his contributions
to mathematics through his students are summarised:-
All of the most important mathematical work
of the 4th century was done by friends or pupils of Plato.
The first students of conic sections, and possibly Theaetetus,
the creator of solid geometry, were members of the Academy.
Eudoxus of Cnidus - author of the doctrine of proportion expounded
in Euclid's "Elements", inventor of the method of
finding the areas and volumes of curvilinear figures by exhaustion,
and propounder of the astronomical scheme of concentric spheres
adopted and altered by Aristotle - removed his school from
Cyzicus to Athens for the purpose of cooperating with Plato;
and during one of Plato's absences he seems to have acted
as the head of the Academy. Archytas, the inventor of mechanical
science, was a friend and correspondent of Plato.
In mathematics Plato's name is attached to
the Platonic solids. In the Timaeus there is a mathematical
construction of the elements (earth, fire, air, and water),
in which the cube, tetrahedron, octahedron, and icosahedron
are given as the shapes of the atoms of earth, fire, air,
and water. The fifth Platonic solid, the dodecahedron, is
Plato's model for the whole universe.
Plato's beliefs as regards the universe were
that the stars, planets, Sun and Moon move round the Earth
in crystalline spheres. The sphere of the Moon was closest
to the Earth, then the sphere of the Sun, then Mercury, Venus,
Mars, Jupiter, Saturn and furthest away was the sphere of
the stars. He believed that the Moon shines by reflected sunlight.
Perhaps
the best overview of Plato's views can be gained from examining
what he thought that a proper course of education should consist.
Here is his course of study :-
... the exact sciences - arithmetic, plane
and solid geometry, astronomy, and harmonics - would first
be studied for ten years to familiarise the mind with relations
that can only be apprehended by thought. Five years would
then be given to the still severer study of 'dialectic'. Dialectic
is the art of conversation, of question and answer; and according
to Plato, dialectical skill is the ability to pose and answer
questions about the essences of things. The dialectician replaces
hypotheses with secure knowledge, and his aim is to ground
all science, all knowledge, on some 'unhypothetical first
principle'.
Plato's Academy flourished until 529 AD when
it was closed down by the Christian Emperor Justinian who
claimed it was a pagan establishment. Having survived for
900 years it is the longest surviving university known.
- J J O'Connor and E F Robertson |