But does it really?
I know for sure that I feel the sensation of a chair because I feel that sensation directly. I can see the chair, touch it, or sit on it. All these sensations I can vouch for personally. But as for the physical reality of the chair, I’m pretty confident about that too, but it is one step removed from my direct experience inasmuch as I am not myself the chair. I only sense the existence of the chair secondhand, whereas I experience my own existence first hand. So should I be more confident about my own existence as a conscious being or about the existence of the chair as a physical reality? Surely my own consciousness takes priority.
Dennett seems to say we should be sure about the existence of the chair, but our own consciousness is a kind of delusion. But this kind of materialism is self defeating since it is only through our conscious experience that we know anything about the physical world in the first place. If we doubt our consciousness then how can we know anything about the physical world?