This paper aims to present the main aspects of Bas C. van Fraassen’s constructive empiricism, particularly regarding the problem of scientific success. In this way, the conceptions of the observable and the unobservable and their relations with the arguments ‘of miracle’ and ‘cosmic coincidence’, both criticized by van Fraassen, will be examined. The answers by authors who defend scientific realism will then be presented, as a counterpoint to the arguments of constructive empiricism. In the end, some more possible difficulties of constructive empiricism will be analyzed and a proposal to surpass them will be presented.