The inward movement of light is familiar enough. As you look at this page, reflected light moves from the page through the electromagnetic field into your eyes. The lenses of your eyes focus the light to form upside-down images on your retinas. This light falling on your retinal rod and cone cells causes electrical changes within them, which trigger off patterned changes in the nerves of the retina. Nerve impulses move up your optic nerves and into the brain, where they give rise to complex patterns of electrical and chemical activity. So far, so good. All these processes can be, and have been, studied in great detail by neurophysiologists and other experts on vision and brain activity.
But then something very mysterious happens. You consciously experience what you are seeing, the page in front of you. You also become conscious of the printed words and their meanings. From the point of view of the standard theory, there is no reason why you should be conscious at all. Brain mechanisms ought to go on just as well without consciousness...read more>>>...