Inference to the Best Explanation has become the subject of a lively debate in the philosophy of science. Scientific realists maintain, while scientific antirealists deny, that it is a compelling rule of inference. It seems that any attempt to settle this debate empirically must beg the question against the antirealist. The present paper argues that this impression is misleading. A method is described that, by combining Glymour's theory of bootstrapping and Hacking's arguments from microscopy, allows us to test IBE without begging any antirealist issues.