西瓜 10

As we already noted above, in a sense, logically valid formulas “do not contain information” (are “content-free”) − just because they are true in all interpretations, i.e. they are true independently of the “meaning” of language primitives.

— Introduction to Mathematical Logic

— Hyper-textbook for students

— Vilnis Detlovs and Karlis Podnieks

2013.10.06 Sunday ACHK