Am I correct that tautologies and contradictions are NOT truth-functional?

We call a statement truth functional if its truth value depends on truth value of its parts. Like A⊃B can be true or false, depending on truth values of A and B.

But, it's not the case with contradictions and tautologies. Like Av~A will always be true, no matter truth value of A.

From this I conclude that tautologies and contradictions are not truth functional. Am I correct? Or do I miss something?

• No. We call an expression truth functional if its truth value can be determined from truth values of its parts alone (without extra information about their structure and "meaning"). It no more has to "depend" on them than the value of x-x in arithmetic has to "depend" on the value of x. If it can be determined even without knowing x so much the better, f(x)=0 is still a function of x. Sep 16, 2021 at 6:40
• See Truth function. Sep 16, 2021 at 7:06
• @Conifold OK, got it Sep 16, 2021 at 8:28
• Usually the logical connectives (⊃,~,V, etc) are said to truth-functional, not the statements that contain them. Sep 16, 2021 at 15:09