Factorials are staggeringly large! The number of ways to order a single standard 52-card deck is on the order of magnitude of 10^67, which is in the range of the estimated number of atoms in the Milky Way.
Early chopsticks were primarily used for cooking, as they could reach into pots of boiling liquids.
It wasn't until around 400 ACE that they started to be used as utensils, due in part to a population boom that required maximizing limited food by chopping it into tiny pieces.
Legumes have a high amount of lectins, which can be toxic -- though nonlethal -- in humans. Red kidney beans in particular contain high levels of a certain lectin, so that eating even a few raw can make you ill!