Pythagoras Essay, Research Paper Pythagoras of Samos is often described as the first pure mathematician. He is an extremely important figure in the development of mathematics yet we know

Pythagoras Essay, Research Paper

Pythagoras of Samos is often described as the first pure mathematician. He is an

extremely important figure in the development of mathematics yet we know

relatively little about his mathematical achievements. Unlike many later Greek

mathematicians, where at least we have some of the books which they wrote, we

have nothing of Pythagoras’s writings. The society which he led, half religious

and half scientific, followed a code of secrecy which certainly means that today

Pythagoras is a mysterious figure. We do have details of Pythagoras’s life from

early biographies which use important original sources yet are written by

authors who attribute divine powers to him, and whose aim was to present him as

a god-like figure. What we present below is an attempt to collect together the

most reliable sources to reconstruct an account of Pythagoras’s life. There is

fairly good agreement on the main events of his life but most of the dates are

disputed with different scholars giving dates which differ by 20 years. Some

historians treat all this information as merely legends but, even if the reader

treats it in this way, being such an early record it is of historical

importance. Pythagoras’s father was Mnesarchus ([12] and [13]), while his mother

was Pythais [8] and she was a native of Samos. Mnesarchus was a merchant who

came from Tyre, and there is a story ([12] and [13]) that he brought corn to

Samos at a time of famine and was granted citizenship of Samos as a mark of

gratitude. As a child Pythagoras spent his early years in Samos but travelled

widely with his father. There are accounts of Mnesarchus returning to Tyre with

Pythagoras and that he was taught there by the Chaldaeans and the learned men of

Syria. It seems that he also visited Italy with his father. Little is known of

Pythagoras’s childhood. All accounts of his physical appearance are likely to be

fictitious except the description of a striking birthmark which Pythagoras had

on his thigh. It is probable that he had two brothers although some sources say

that he had three. Certainly he was well educated, learning to play the lyre,

learning poetry and to recite Homer. There were, among his teachers, three

philosophers who were to influence Pythagoras while he was a young man. One of

the most important was Pherekydes who many describe as the teacher of

Pythagoras. The other two philosophers who were to influence Pythagoras, and to

introduce him to mathematical ideas, were Thales and his pupil Anaximander who

both lived on Miletus. In [8] it is said that Pythagoras visited Thales in

Miletus when he was between 18 and 20 years old. By this time Thales was an old

man and, although he created a strong impression on Pythagoras, he probably did

not teach him a great deal. However he did contribute to Pythagoras’s interest

in mathematics and astronomy, and advised him to travel to Egypt to learn more

of these subjects. Thales’s pupil, Anaximander, lectured on Miletus and

Pythagoras attended these lectures. Anaximander certainly was interested in

geometry and cosmology and many of his ideas would influence Pythagoras’s own

views. In about 535 BC Pythagoras went to Egypt. This happened a few years after

the tyrant Polycrates seized control of the city of Samos. There is some

evidence to suggest that Pythagoras and Polycrates were friendly at first and it

is claimed [5] that Pythagoras went to Egypt with a letter of introduction

written by Polycrates. In fact Polycrates had an alliance with Egypt and there

were therefore strong links between Samos and Egypt at this time. The accounts

of Pythagoras’s time in Egypt suggest that he visited many of the temples and

took part in many discussions with the priests. According to Porphyry ([12] and

[13]) Pythagoras was refused admission to all the temples except the one at

Diospolis where he was accepted into the priesthood after completing the rites

necessary for admission. It is not difficult to relate many of Pythagoras’s

beliefs, ones he would later impose on the society that he set up in Italy, to

the customs that he came across in Egypt. For example the secrecy of the

Egyptian priests, their refusal to eat beans, their refusal to wear even cloths

made from animal skins, and their striving for purity were all customs that

Pythagoras would later adopt. Porphyry in [12] and [13] says that Pythagoras

learnt geometry from the Egyptians but it is likely that he was already

acquainted with geometry, certainly after teachings from Thales and Anaximander.

In 525 BC Cambyses II, the king of Persia, invaded Egypt. Polycrates abandoned

his alliance with Egypt and sent 40 ships to join the Persian fleet against the

Egyptians. After Cambyses had won the Battle of Pelusium in the Nile Delta and

had captured Heliopolis and Memphis, Egyptian resistance collapsed. Pythagoras

was taken prisoner and taken to Babylon. Iamblichus writes that Pythagoras (see

[8]):- … was transported by the followers of Cambyses as a prisoner of war.

Whilst he was there he gladly associated with the Magoi … and was instructed

in their sacred rites and learnt about a very mystical worship of the gods. He

also reached the acme of perfection in arithmetic and music and the other

mathematical sciences taught by the Babylonians… In about 520 BC Pythagoras

left Babylon and returned to Samos. Polycrates had been killed in about 522 BC

and Cambyses died in the summer of 522 BC, either by committing suicide or as

the result of an accident. The deaths of these rulers may have been a factor in

Pythagoras’s return to Samos but it is nowhere explained how Pythagoras obtained

his freedom. Darius of Persia had taken control of Samos after Polycrates’ death

and he would have controlled the island on Pythagoras’s return. This conflicts

with the accounts of Porphyry and Diogenes Laertius who state that Polycrates

was still in control of Samos when Pythagoras returned there. Pythagoras made a

journey to Crete shortly after his return to Samos to study the system of laws

there. Back in Samos he founded a school which was called the semicircle.

Iamblichus [8] writes in the third century AD that:- … he formed a school in

the city [of Samos], the ’semicircle’ of Pythagoras, which is known by that name

even today, in which the Samians hold political meetings. They do this because

they think one should discuss questions about goodness, justice and expediency

in this place which was founded by the man who made all these subjects his

business. Outside the city he made a cave the private site of his own

philosophical teaching, spending most of the night and daytime there and doing

research into the uses of mathematics… Pythagoras left Samos and went to

southern Italy in about 518 BC (some say much earlier). Iamblichus gives some

reasons for him leaving. First he comments on the Samian response to his

teaching methods. Pythagoras founded a philosophical and religious school in

Croton (now Crotone, on the east of the heal of southern Italy) that had many

followers. Pythagoras was the head of the society with an inner circle of

followers known as mathematikoi. The mathematikoi lived permanently with the

Society, had no personal possessions and were vegetarians. They were taught by

Pythagoras himself and obeyed strict rules. The beliefs that Pythagoras held

were [2]:- (1) that at its deepest level, reality is mathematical in nature, (2)

that philosophy can be used for spiritual purification, (3) that the soul can

rise to union with the divine, (4) that certain symbols have a mystical

significance, and (5) that all brothers of the order should observe strict

loyalty and secrecy. Both men and women were permitted to become members of the

Society, in fact several later women Pythagoreans became famous philosophers.

The outer circle of the Society were known as the akousmatics and they lived in

their own houses, only coming to the Society during the day. They were allowed

their own possessions and were not required to be vegetarians. Of Pythagoras’s

actual work nothing is known. His school practised secrecy and communalism

making it hard to distinguish between the work of Pythagoras and that of his

followers. Certainly his school made outstanding contributions to mathematics,

and it is possible to be fairly certain about some of Pythagoras’s mathematical

contributions. First we should be clear in what sense Pythagoras and the

mathematikoi were studying mathematics. They were not acting as a mathematics

research group does in a modern university or other institution. There were no

‘open problems’ for them to solve, and they were not in any sense interested in

trying to formulate or solve mathematical problems. Rather Pythagoras was

interested in the principles of mathematics, the concept of number, the concept

of a triangle or other mathematical figure and the abstract idea of a proof. As

Brumbaugh writes in [3]:- It is hard for us today, familiar as we are with pure

mathematical abstraction and with the mental act of generalisation, to

appreciate the originality of this Pythagorean contribution. In fact today we

have become so mathematically sophisticated that we fail even to recognise 2 as

an abstract quantity. There is a remarkable step from 2 ships + 2 ships = 4

ships, to the abstract result 2 + 2 = 4, which applies not only to ships but to

pens, people, houses etc. There is another step to see that the abstract notion

of 2 is itself a thing, in some sense every bit as real as a ship or a house.

Pythagoras believed that all relations could be reduced to number relations. As

Aristotle wrote:- The Pythagorean … having been brought up in the study of

mathematics, thought that things are numbers … and that the whole cosmos is a

scale and a number. This generalisation stemmed from Pythagoras’s observations

in music, mathematics and astronomy. Pythagoras noticed that vibrating strings

produce harmonious tones when the ratios of the lengths of the strings are whole

numbers, and that these ratios could be extended to other instruments. In fact

Pythagoras made remarkable contributions to the mathematical theory of music. He

was a fine musician, playing the lyre, and he used music as a means to help

those who were ill. Pythagoras studied properties of numbers which would be

familiar to mathematicians today, such as even and odd numbers, triangular

numbers, perfect numbers etc. However to Pythagoras numbers had personalities

which we hardly recognise as mathematics today [3]:- Each number had its own

personality – masculine or feminine, perfect or incomplete, beautiful or ugly.

This feeling modern mathematics has deliberately eliminated, but we still find

overtones of it in fiction and poetry. Ten was the very best number: it

contained in itself the first four integers – one, two, three, and four [1+2+3+4

= 10] – and these written in dot notation formed a perfect triangle. Of course

today we particularly remember Pythagoras for his famous geometry theorem.

Although the theorem, now known as Pythagoras’s theorem, was known to the

Babylonians 1000 years earlier he may have been the first to prove it.