Thales of Miletus (~-630 - ~-543)
Thales was born in Miletus around 630 BC. It is not known exactly when he was born, but there is only an estimate based on other scholars. He is mentioned in various texts and is described as progressive, innovative and a pioneer of his time. There is a controversy concerning his written works; some scholars say that he did not leave any written texts, while others attribute some texts that have been saved, including About Solstices and About Equinoxes. Herodotus mentions that Thales had successfully predicted the solar eclipse of 585 BC. It is also disputed whether he was ever married; a son named Kyvisthos is mentioned. According to one theory, he was indeed his son, meaning he was married. The other theory supports that he was his nephew, whom he practically adopted. This is enhanced by some stories mentioning the reason for Thales remaining single; one story says that his mother asked him to get married, but he would say he was too young; after some years passed, he would tell her that he was too old. Another story mentioned by Plutarch says that when Solon asked Thales why he didn’t want to get married and have heirs, he said out of love towards the children.
Some texts mention that he was also involved in entrepreneurial activities. According to Aristotle, his involvement in business was not to make money; his fellow citizens questioned the use of philosophy in everyday life, since it does not help them get rich. Thales, having predicted through planetary movements that the fertility of the ground would be increased the following year, he rented all olive presses of Miletus. He was correct and because of increased demand, he became rich; thus, he showed to his fellow citizens that wisdom can definitely help them financially, but that this was not its purpose.
Thales was the first person who tried to explain natural phenomena based on natural processes. It is characteristic how he tried to explain earthquakes; the Earth floats on water and trembles because of waves. Concerning theology, he believed that the world was full of gods and that the soul is something that moves. In Physics, he discovered solstices, the fact that the Moon does not emit its own light, as well as electricity and magnetism, based on the properties of amber and mineral magnetite respectively. He was also a great geometer and astonished the Egyptians when he calculated the height of the Pyramids, by measuring the length of their shadow and comparing it to the shadow of a stick he put on the ground.