Vision and Evolution (A Critique of Dawkins)

[John 6IX Breezy]

The issue with sensory organs is that they are there to inform or guide behavior. Given that perception is a highly interpretive process, possessing "half an eye" as you call it, will most likely lead to behaviors that are disadvantageous. Now its worth mentioning that I consider something to be "half an eye" when it is compared to the rest of that organisms structures, not when compared across organisms. So I wouldn't label phototaxic bacteria as having "half an eye" because they come equipped to adequately transform that information into movement. There is a balance of structure there, despite its minimal composition.

Soo you are saying that having bad vision is worse than beeing blind?

In a lot of situations, yes. Take for example a condition that often results from strokes in which the person is unable to see the left half of their visual field. By unable to see I don't mean there is a blackness in that half of their visual field, I mean that it is absent from consciousness entirely, as if leftness didn't exist. This leads to odd behaviors, from not eating the left half of a plate of food to wearing clothes on only half their body. They are guiding their behavior according to a misinformed perception of the environment. This misperception will almost certainly lead to detrimental behaviors that a blind person would not need to worry about.

When it comes to behavior and perception. My position is that no sensory information is better that misleading sensory information. It is better for you to not see the knife on the table, than to see it as an edible fruit.