A rule of inference in propositional logic. Written 'com.' for short. It goes like this:

(P∨Q) = (Q∨P)

And

(Q∧P) = (P∧Q)

*"I have an apple or an orange"* is the same as *"I have an orange or an apple".*

And...

*"I have an apple and an orange"* is the same as *"I have an orange and an apple".*

A very simple and intuitive rule, but logicians like to be very precise.

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