aka law of parsimony

Among competing hypotheses, the one with the fewest assumptions should be selected

https://www.wikiwand.com/en/Occam's_razor

Formalized in Solomonoff's theory of Universal inductive inference

Trivial example of Occam's razor being true: the case when one event/hypothesis includes the other

See Simplicity

Sharpening Occam’s Razor

Occam algorithm

See here