  The confirmatory form of the probabilistic argument is more modest; it aims to show that there is a considerable contribution to the argument for \(M\) arising from the facts indicated (McGrew and McGrew 2009). It has been objected (Oppy 2006: 5–6) that probabilistic arguments of this sort are of no interest unless they are founded on all of the relevant available evidence. But this objection would, if legitimate, count equally against the use of arguments from comparison of likelihoods in scientific reasoning, where they are ubiquitous. More cautiously, one might ask why an argument that places no definite restrictions on the probability of \(M\) should be of any interest. One answer would be that a successful confirmatory argument may shift the burden of proof. If there is a substantial body of evidence in favor of \(M\), it is incumbent on those who deny \(M\) to explain in some detail either (1) why the antecedent presumption against \(M\) should override this evidence or (2) what the other evidential considerations are that mitigate against \(M\).