What am I?

Blaise Pascal, Pensees #108 (Krailsheimer, p. 57):

What part of us feels pleasure? Is it our hand, our arm, our flesh, or our blood? It must obviously be something immaterial.

Is it my eyeglasses that see yonder mountain? No, they are merely part of the instrumentality of vision. Is it my eyes that see the mountain, or any part of the eye (retina, cornea, etc.)? The optic nerves or the visual cortex? All of this stuff hooked together? If you say yes, then what accounts for the unity of the visual experience? Eyeglasses, eyes, and all the rest are merely parts of the instrumentality of visual consciousness, its physical substratum. Not eye, but I see the mountain. What am I? Arguably, if not obviously, something immaterial.