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 Feb24 awarded Notable Question Jun14 awarded Good Question Nov9 awarded Yearling Jan11 awarded Popular Question Jun28 awarded Scholar Jun28 accepted In classical logic, why is $(p\Rightarrow q)$ True if both $p$ and $q$ are False? Jun28 comment In classical logic, why is $(p\Rightarrow q)$ True if both $p$ and $q$ are False? I had been reading line 3 (and 4 for that matter) as 'if p were to be true, then q', then inspecting the value of p, setting it to true, and then evaluating the statement. Line 3 leaves (T,T) => T like line 1, so no problem. Line 4 leaves (T,F) => T unlike line 2 (T,F) => F, so a problem. Jun28 awarded Supporter Jun28 comment In classical logic, why is $(p\Rightarrow q)$ True if both $p$ and $q$ are False? Thinking of it as a promise and that you are evaluating the promise itself and not the causality is extremely helpful. Thanks a lot. Jun28 awarded Nice Question Jun28 awarded Announcer Jun28 awarded Student Jun28 asked In classical logic, why is $(p\Rightarrow q)$ True if both $p$ and $q$ are False?