Talk:Cantor-Bernstein-Schröder Theorem/Proof 5

I think this proof needs to explicitly mention that f is an injection in order to use the cantor bernstein lemma. I can make the appropriate changes (minor modifications) some time later.


 * I may be missing something but does it not already? Second line: "Let $f: S \to T$ and $g: T \to S$ be injections." --prime mover (talk) 13:52, 22 December 2016 (EST)
 * the injetion, f, is in the premises. but nowhere in the proof is f even mentioned let alone that it is an injection. I dont see how a legitimate proof can use only the injection g and not f.  But I can see how to make a proof that uses f. Wanfactory (talk) 13:57, 22 December 2016 (EST)