Ancient Greece was an immensely fertile producer of philosophers who pondered such fundamental questions as the meaning and origins of life.
Ancient Greece was an immensely fertile producer of philosophers who pondered such fundamental questions as the meaning and origins of life.
Some of their theories were way ahead of their time, but Archimedes and Eratosthenes were among very few to back them up with experimental evidence.
Ancient Greece, as it is now known, thrived from around 900BC to 30BC and extended far beyond Greece itself.
Many of its important figures lived on far-flung lands around the eastern Mediterranean.
It was not quite an empire – though its influence was often spread by conquering neighbouring states.
Ancient Greece was a culture, a way of life.
One of its main intellectual centres was Alexandria, on the northern coast of Egypt.
It boasted a huge library containing hundreds of thousands of scrolls – the ideas and observations of Ancient Greece’s greatest thinkers.
Eratosthenes (c.276 BC–194 BC) was head librarian, but he was also an accomplished mathematician, astronomer and geographer.
Modern academics disagree on the accuracy of his calculation of the Earth’s circumference because they are not sure about the value of ‘stadia’, the units he used.
But one ‘stadion’ was normally about 185 metres – and with that value Eratosthenes’ result was very close to the actual figure.
Archimedes (c.287 BC–212 BC) was a friend of Eratosthenes.
The two men met at Alexandria, though Archimedes spent most of his life in his birthplace – a Greek port in Sicily called Syracuse.
He was well known in his day, mainly for designing huge machines to defend Syracuse against invading Roman warships.
As a physicist, Archimedes discovered the concept of the centre of gravity, and analysed how levers and pulleys work.
But his greatest contributions were in mathematics – he was centuries ahead of his time – and in applying mathematics to the real world.
The incident involving his bath is famous, but probably only a legend.
It relates to his discovery of what is now known as Archimedes’ Principle, which states that a submerged object is pushed upwards by a force equal to the weight of the fluid it displaces.
Previous civilisations created myths to explain how the world works, and Ancient Greek ‘scientists’ were keen to replace them with more rational explanations.
They were not true scientists: most refused to test their theories on the grounds that experiments are artificial situations removed from the real world.
Today, rigorous testing of new theories with meticulous experiments is central to modern science.
Any new research must also be checked by other scientists before it can be published – a process called ‘peer review’.
Perhaps the most famous Greek philosopher was Aristotle (384–322 BC).
He devised hundreds of explanations about the natural world, space, the nature of matter, and forces and motion.
Unfortunately, many of his ideas were certainly wrong but were taught to students of ‘natural philosophy’ for hundreds of years.
They were challenged only during the Renaissance period in 16th and 17th century Europe.
Ancient Greek culture had a strong influence on the emerging Roman Empire.
But as the Western half of the Roman Empire fell in the 5th century AD, most of the accumulated Greek and Roman knowledge was lost.
The library at Alexandria had been destroyed, and the Western world hurtled into a period of disorganisation and conflict often called ‘the Dark Ages’.
