>[!abstract] >The tetractys is a triangular figure consisting of ten points arranged in four rows: one, two, three, and four points in each row, which is the geometrical representation of the fourth triangular number. As a mystical symbol, it was very important to the secret worship of [[Pythagoreanism]]. There were four seasons, and the number was also associated with planetary motions and music. ("Tetractys", 2025). ## References - Tetractys. (2025, March 25). In *Wikipedia*. https://en.wikipedia.org/w/index.php?title=Tetractys&oldid=1253115945