>>14407624Your question is retarded so I'm not going to answer it, but here's something very useful. Say, you want to prove an implication that can be (loosely) translated to something of the form , for example
"Given a and b are reals, if ab = 0, then a = 0 or b = 0"
Propositional calculus gives you the ability to study the equivalence of propositions only by virtue of form and not a single drop of content is relevant to it, so thanks to it you know FOR SURE the following equivalence holds
Therefore, your original problem of proving "ab = 0 implies a = 0 or b = 0" for real numbers a,b, translates to proving "ab = 0 and a =/=0 implies b = 0".
tl;dr formal logic allows you to unambiguously reinterpret propositions regarding their form
