We don't know how we see, but we see.
The traditional belief is that light shines on objects, is reflected of those objects into our eyes, and from stimulation of certain parts of the brain via the optic nerve we see the images that the creator God wishes us to see.
But out there is total darkness. Electromagnetic radiation of the visible wavelength has no light in it. It is only visible because it is of the wavelengths that stimulate the eyes into stimulating the brain's centres of vision - the brain presents it as such, and our thoughts label it as such. The sensation of light itself is created by the brain. The association of light (electromagnetic radiation of the visible spectrum) with light (stimulation of the brain's centres for vision) is purely and wholly arbitrary, and only comes about because the brain itself generates images that its centres of vision (an image it generates for us) are stimulated by a body organ (the eye, another image it generates for us) that is sensitive to a spectrum of electromagnetic radiation (expression and concept derived from the same brain's images, also a feature of the brain).
We dream. There is no light shining on our eyes and nothing stimulates the brain's centres of vision from the outside. Yet we see all kinds of images just as when we are awake.
What is light (as perceived in the mind) then? What then shines within the mind, and what is it reflected off to create the images from patterns of light that we call vision, just as in the physical world electromagnetic radiation shines from the Sun and is reflected off objects? That by which the brain itself is perceived, and labelled as the brain?
We have memories. Those memories can be as clear, and as bright as in so called real life. Just as in our dreams the images can be as life like as in our so called waking state. If the images are just as bright and just as clear, who is to say that the so called reality of our waking state, isn't just a dream, or just a memory, some kind of real time memory or real time dream? If then we were to wake up into what would be a proper waking state, how could we be sure that that state would be the true waking state? How would it differ from the other states?
What is sound, not sound as in vibrations within the air that affect our hearing organ, but the origin within the brain and what it is reflected off that we call sound? Does all sound itself have a point source, analogous to the Sun, from which pure sound originates, and then is reflected of objects to create its variations, or do all the variations of sound originate from different point sources?
What of our senses of smell, touch, and taste? Do they have point sources from which they originate, and objects from which they are reflected within the brain?
In effect, what are the equivalents of photons of inner senses within the brain, just as by analogy the world of our vision has photons?
Does the brain have photons of its own? Do the images we record in our memory of our sense experiences have an inner source of photons?
What of our thoughts, and emotions?
Consider joy, wonder, our senses of beauty, anger, hatred, sadness, embarrassment, pride, all these inner feelings. What is the origin of the photons of these sensations, and what are they reflected off?
For lack of a better name let us call it the Illuminator. What is the nature of this Illuminator? This Illuminator that creates worlds and experiences for us in our waking life and in our dreams. What is the source of the photons within those dreams, the photons from which the experiences of those dreams, and our emotional responses to those dreams arise?
Seek that Illuminator, find that Illuminator, praise that Illuminator, thank that Illuminator, the Sun of our perceptions.
Seek it and honour it.