Sensorimotor theory claims that what you do and what you know how to do constitutes your visual experience. Central to the theory is the claim that such experience depends on a special kind of knowledge or understanding. I assess this commitment to knowledge in the light of three objections to the theory: the empirical implausibility objection, the learning/post-learning objection and the causal-constitutive objection. I argue that although the theory can respond to the first two objections, its commitment to know-how ultimately renders it vulnerable to the third and arguably most serious objection. I then suggest that sensorimotor theory has two options: concede the causal-constitutive objection or challenge it. I shall argue for the latter. I will claim that a radical sensorimotor theory offers the best means of responding to this objection.