When proving a biconditional, sometimes the writer says "I'll prove the converse first". I want to say I'll prove left-to-right first. How to say that? I don't want to put a left to right arrow. I prefer words.
Also, how can I say I'll prove the converse of the statement but my strategy is to prove the contrapositive of the converse. Should I just say "I'll prove the contrapositive of the converse"? I'd like to use the standard lingo, but I'm not actually used to reading such statements. I can't remember seeing anyone using these descriptions.