The understanding of irrational numbers goes back to ancient Greek mathematicians from [katex] 6 [/katex]th century BCE. The story is told that Hippasus of Metapontum, a member of the Pythagorean school, was the one who discovered the existence of irrational numbers. The discovery of irrational numbers was challenged at the time, because it challenged some of the Pythagorean beliefs at the time.