All Thinkers

Thinkers Timeline

Key thinkers across history — grouped by era, colour-coded by discipline. Click any card to explore ideas, quotations, and classroom contexts.

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Ancient — pre-500 CE
Archimedes c. 287 BCE - c. 212 BCE · Syracuse, Sicily (Hellenistic Greek world)
Archimedes was a Greek mathematician, scientist, and engineer. He was born around 287 BCE in Syracuse, a Greek city on the island of Sicily. We know little about his early life. His father was an astronomer named Phidias. He may have studied for a time at the great Library of Alexandria in Egypt, though this is not certain. Most of his life, however, was spent in Syracuse. In his time, Syracuse was an independent Greek-speaking city. The Roman Republic was growing stronger and would soon swallow most of the Mediterranean world. Archimedes worked closely with the king of Syracuse, Hiero II, and later with Hiero's grandson Hieronymus. He served the city as both a thinker and an inventor. In the year 212 BCE, Roman forces attacked Syracuse. Archimedes was about 75 years old. He had designed weapons to defend the city, including powerful catapults and machines that lifted enemy ships out of the water. The Romans took the city after a long siege of about two years. The traditional story is that a Roman soldier killed Archimedes during the chaos, even though the Roman general Marcellus had ordered that he be spared. According to later writers, Archimedes was working on a mathematical problem when the soldier arrived. He asked not to have his diagrams disturbed. The soldier killed him anyway. His tomb in Syracuse was lost for centuries. The Roman writer Cicero claimed to have rediscovered it nearly 140 years after his death.
"Eureka! I have found it!"
Hypatia of Alexandria c.350-415 CE · Alexandria, Roman Egypt
Hypatia of Alexandria (c.350-415 CE) was a mathematician, astronomer, and philosopher who taught in the Egyptian city of Alexandria during the late Roman Empire. She was the daughter of the mathematician Theon, a scholar connected to the great library of Alexandria, and she received an exceptional education in the mathematical and philosophical traditions of the Greek-speaking world. By her maturity she was a renowned teacher in the Neoplatonist tradition, giving public lectures and leading a private circle of students that included Christians, pagans, and members of the wealthy families of the eastern Roman Empire. She is known to have written commentaries on the great mathematical texts of her time, including Diophantus's Arithmetica, Apollonius's Conics, and Ptolemy's Almagest, and to have worked closely with her father on the preservation and editing of earlier mathematical works. Her own writings do not survive; we know her through letters from her students, particularly Synesius of Cyrene, who became a Christian bishop but continued to honour her as his intellectual guide. Alexandria in her lifetime was politically and religiously turbulent. In 415 CE she was killed by a Christian mob in the streets of the city, in circumstances that have been debated by historians ever since. Her death has been remembered for sixteen centuries as a marker of something lost.
"Reserve your right to think, for even to think wrongly is better than not to think at all."