In his article “Constructive Empiricism Now” van Fraassen chooses an extremely interesting example to defend his thesis that scientific theories are only representations, so that the aim of science is to give us reliable, empirically adequate, descriptions of the observable aspects of the world. For him, there is no continuum of observable/unobservable, as he draws a line of distinction at a point that eliminates from his ontology such cases as fields of forces and sub-atomic particles. As a result, he puts (...) forward the position that electronic images in the microscope and subatomic particles are “public hallucinations” and not “real things”. What I thus propose to do is to examine van Fraassen’s anti-realism through the looking class of realism, my aim being to defend a realist view of science: To this purpose, I will focus on two main issues: (a) the question of representations in science and in particular of images we “see” through a microscope and (b) the question of the criteria for defining physical reality. In this context, I will argue that van Fraassen’s definition of the “real” is an anti-realist version of the positivist trend, which cannot fit in the picture of science that emerges today. To understand, thus, the world of physics we need to re-examine our definition of reality and make space for an ontology that goes beyond the well-defined spatio-temporal existence of what van Fraassen calls a “real thing”. (shrink)