 Now it is certainly true that if one is defending a version of the argument from evil that supports only a probabilistic conclusion, one needs to consider what sorts of positive reasons might be offered in support of the existence of God. But Plantinga and Reichenbach are advancing a rather stronger claim here, for they are saying that one needs to look at all of the traditional theistic arguments, such as the cosmological and the teleological.  They are claiming, in short, that if one of those arguments turned out to be defensible, then it might well serve to undercut the argument from evil.