The Greeks did know about irrational numbers. They could draw a right triangle whose legs were 1 and 1. They knew that the length of the hypotenuse (a number th

The Greeks did know about irrational numbers. They could draw a right triangle whose legs were 1 and 1. They knew that the length of the hypotenuse (a number that we call the square root of two) couldn't be represented as the ratio between any two integers, yet it had a length.