The "Positive Argument" for Constructive Empiricism and Inference to the Best Explanation

In this paper, I argue that the positive argument for Constructive Empiricism (CE), according to which CE makes better sense of science, and of scientific activity, than realism does (van Fraassen in The scientific image, Clarendon Press, Oxford, 1980, 73), is an Inference to the Best Explanation (IBE). But constructive empiricists are critical of IBE, and thus they have to be critical of their own positive argument for CE. If my argument is sound, then constructive empiricists are in the awkward position of having to reject their own positive argument for CE by their own lights.