In the 6th century, Hibbs, a scholar of Pythagoras School, discovered an irrational number when studying a square with a long diagonal length. Pythagoras School did not realize that it was thrown into the sea and drowned, which led to the first crisis in the history of mathematics, that is, it did not recognize rationality and prevented its spread or it was similar. In the 6th century A.D., Hebrew, a scholar of Pythagoras School, discovered the irrational number when he was studying the length of 1 square diagonal, which was not recognized by Pythagoras School and was drowned in the sea, resulting in the first crisis in the history of mathematics, that is, not recognizing the irrational number and preventing its spread.