Multiple proofs are better than one

Having two or more proofs (arguments/derivations) is better than having just one.  All real logic is fuzzy (approximate) in the sense that each logical step may be wrong (at least some of the time) and each quantity being manipulated is only a rough (approximate) description of something observed in the real world.  In some idealized logics 2 proofs may be no better than 1 proof.  In some more realistic logics 2 proofs are better than just 1.