The paper describes critique as a definition of the limits that may be reached by sensory perception (in both the knowledge and methodological senses). Although not always explicite, Bošković defined these limits quite clearly, on the whole. Knowledge-wise, Bošković set two limits to sensory perception: first, regarding its object, and second, regarding the form in which it knows its object. In the first (object) sense it is limited to those matter properties which are related to motion through which bodies affect our sensory organs, and, furthermore, among these properties, to those that the intensity of which is within the limits of our sensory powers. In the other (formal) sense Bošković simply limited it to the shape of the object (the properties), to the phenomenon (in contrast to the faithful reflection). Methodology-wise, Bošković’s theory-of-knowledge critique of sensory perception results, on the one hand, in the principle of close reconsideration of ideas acquired through the senses, and on the other hand, in the appeal to use reflection in order to form ideas more appropriate to the true reason and the nature of things itself. Furthermore, it also provides the form in which the ideas acquired through the senses become the starting points of scientific research –the form of the phenomenon viable to correction and replacement with something better, more true.