Can philosophical theories of perception defer to perceptual science when fixing their ontological commitments regarding the objects of perception? Or in other words, can perceptual science inform us about the nature of perception? Many contemporary mainstream philosophers of perception answer affirmatively. However, in this essay I provide two arguments against this idea. On the one hand, I will argue that perceptual science is not committed to certain assumptions, relevant for determining perceptual ontology, which however are generally relied upon by philosophers when interpreting such science. On the other hand, I will show how perceptual science often relies on another assumption, which I call the ‘Measuring instrument conception’ of sensory systems, which philosophers of perception should clearly reject. Given these two symmetric lines of argument, I will finally suggest that we ought to think differently about the relationship between perceptual science and the philosophy of perception.