If any of you have a moderate astigmatism, you may have observed this - if not, you'll have to take my word for it.
If I close my weak eye*, I find that after a few seconds, the image from the strong eye, even though it is closed, tries to creep into my visual field. It is not difficult at this point to 'look through' the eye that is closed (seeing phosphenes or just darkness). Reversing the test, with my weak eye closed, there is no creeping effect and it is not really possible for me to look through the eye that is closed. In a universe of functionalism or comp, I would expect that this would never happen, as my brain should always prioritize the information made available by any eye that is open over that of an eye which is closed. The fact that closing the weak eye instead does not produce the creeping image effect demonstrates that there is no functional purpose which could be served by favoring the strong eye when it is the one which is closed. In some people astigmatism progresses until the develop a wandering eye. The physicalist can claim victory over the functionalist here in that the atrophy of nerve connections to the weak eye and the relative hypertrophy of the nerve connections to the strong eye clearly dominate the functional considerations of the visual mechanism. The creeping image effect also is not immediate, so that it is not the case that the hardware is incapable of maintaining clear vision through the weak eye, it is obviously the inertia of purely physical-perceptual processes which is dragging the function down. Between the physical and the perceptual, which one is driving? It would seem that physics would win here, because the creeping image is not the more aesthetically rich image - however, this is not a case where the aesthetics are determined only from the top down. Remember that both eyes are exposed to the same light. The retinas receive the same total number of photons. The strong eye develops more robust connections to it not because it has more light, but because the shape of the eye is such that the cells (sub-personal agents) of the retina are able to make more sense out of the better focused light. There are not more signals being generated, but clearer signals which carry farther up the ladder from sub-personal optical detection to personal visual sensation. The nerve growth follows the coherence of visual consciousness, not a just a photological nutrient supply. The eye becomes stronger because the brain population is prioritizing higher sensitivity, not because neurons are being pushed around by blind ionic concentration gradients. That sensory priority is the cause of the neurological investment in that eye's sensitivity, so that it is perceptual inertia which drives the creeping image effect not just biological morphology. *which is my left eye. Curious if any of you left brainy types have an astigmatism in the right eye. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
