Archimedes (-287 to -212) was a Greek mathematician from Syracuse, Italy, back when the city was still Greek. He was one of the greatest minds of the ancient world. He gave us the word “Eureka!” and worked out how levers work, but most of all he showed us how you could use numbers to do science.
His use of numbers in science did not catch on in his own time, but it did later when his writings came out in Latin in 1544. Galileo read them and used the same approach, which led to the rise of Western science and our faith in numbers.
Even today Archimedes is worth reading because of how sees and understands the world through number and shapes, through geometry.
He used number and measurement to work out how levers work and how strong they are in different cases. From this he knew there was no limit to what they could do. He said he could move the whole world if he had a place to stand.
Archimedes worked out pi to two places: 3.14. He knew it was somewhere between 3.141 and 3.143.
The word “Eureka!” comes from the time when the king asked Archimedes to find out whether his crown was made of pure gold.
Gold was the heaviest metal known in those days: for a given size, nothing else was so heavy.
The easy way to find out if the crown was pure gold would be to melt it down to a block and compare it to a block of pure gold of the same weight. If the melted down crown was larger, then something was added to the gold. It was not pure.
But Archimedes could not destroy the crown. So he had to find out how much space it took up some other way.
One day as he was getting into his bath he saw the water flow over the sides.
When he saw that he jumped out of his bath and ran through the streets naked shouting “Eureka! Eureka!”, which is Greek for “I have found it! I have found it!”
Meaning he had found out how to measure the size of the crown: by putting it in water and seeing how much water it pushes out. The water it pushes out had to be the same size as the crown.
Archimedes found out the crown was not made of pure gold and the king put the goldsmith to death.
Later the Romans made war on Syracuse for siding with Carthage. To defend the city Archimedes came up with different inventions, like one that turned over ships. It came from his work with levers. The Romans grew to fear him.
When Syracuse was falling, Archimedes was drawing circles in the sand, working on something in geometry. He asked a Roman soldier not to mess up his circles. In spite of orders to take him alive, the soldier killed him.