Theodorus of Cyrene

Theodorus of Cyrene was an ancient Greek mathematician known for his work in geometry around the 5th century BCE. He is best recognized for introducing the concept of incommensurable lengths, particularly in relation to the square root of numbers that cannot be expressed as simple fractions. This work laid important groundwork for later developments in mathematics, such as the understanding of irrational numbers. Theodorus also contributed to the study of geometric figures and was associated with the mathematical school in Cyrene, influencing scholars like Plato and others in the field of mathematics and philosophy.