Numerology is the study of the mystical or divine relationship between numbers and events. It was popular among early mathematicians like Pythagoras but is now considered pseudoscience. Modern numerology incorporates aspects of ancient cultures from Babylon, Greece, Egypt, India, and China. Pythagoras and other early philosophers believed numbers had greater meaning and reality than physical things. Numerology was an unapproved belief after the First Council of Nicaea but some still ascribed spiritual significance to numbers.