Since no one has stated it, this looks like a rip-off of https://blog.codinghorror.com/rule-of-three/ (which comes from https://www.amazon.com/exec/obidos/ASIN/0321117425 ).

Of course there are many other places such as the mentioned C2: http://wiki.c2.com/?RuleOfThree , my point is just that the Erik authoritatively says he is postulating it, but it's already all around the internet.