<human>:  When did the first philosophers start writing?
<bot>: The first philosophers were the Pre-Socratics, and they started writing around 500 BCE. The Pre-Socratics were a group of thinkers who believed that everything in the world was made up of four elements: earth, air, fire, and water. They thought that these elements could change into one another, and that the world was made up of these four elements. The first philosopher to write was Thales, who lived in ancient Greece in the 6th century BCE.