Thought experiments (TEs for short) have become a hot topic in philosophy of science. After platonist, empiricist and naturalist-cognitivist proposals, the present book promises to come up with a Kantian view of both actual experiments and of TEs, in which both categories are brought close together within a slightly apriorist framework, but, fortunately, still kept distinct. The Kantian inspiration shows already at the outset: Buzzoni talks about ‘‘indeterminate multiplicity of categories individually constructed by the mind and tested operationally to solve specific problems’’ (15). Still, already here one wonders how much of (Kantian) apriority is preserved in the picture, in particular since the categories are empirically tested; some weak ‘‘relative apriority’’ might survive, but this seems hardly sufficient for a ‘‘reflexive transcendental conception’’ of scientific enterprise. The operational side is more explicit: We can empirically ascertain the properties of physical bodies only insofar we connect them to concepts and to reproducible actions that make the object interact with other objects. ‘‘These actions are always guided by concepts and values, and it is only for this reason that they have cognitive significance’’ (23). The strongest side of the book is author’s historical erudition, to be felt at every page. In the first chapter, on experiments, the author reminds us of the work of German constructivists (Lorenzen, Janich—who is also the author of a brief Preface to the book) and introduces interesting and rarely cited earlier philosophers of science, like Hugo Dingler. A weakness of the text is a certain sloppiness of formulation, sometimes at crucial points. For instance, we read that ‘‘empirical properties of a body have a meaning that is determinate and in principle univocal’’ (23). The text makes it clear that the properties in question are quite ordinary ones, like hardness and fragility. But the idea that fragility has a meaning, and indeed a univocal one, obviously should not be taken literally; how it should be taken is only half clear from the text.