This chapter outlines Kant’s account of empirical concept formation and discusses two objections that have been advanced against it. Kant holds that we form empirical concepts, such as colour concepts, by comparing sensory representations of individuals, identifying shared features, and abstracting from the differences between them. According to the first objection, we cannot acquire colour concepts in this way because there is no feature that all and only the instances of a given colour share and the boundary between colours is (...) conventional. According to the second objection, assuming that all instances of a given colour share certain features, we can identify them only if we already possess a concept of that colour. None of the two objections is convincing as it stands. Kant can offer replies to both objections that are consistent with his views and with empirical evidence concerning the perception and representation of colours. (shrink)