
Blindsight is a strange brain/mind condition that philosophers like to discuss in the context of discussions about consciousness. People with blindsight have a problem with their visual cortex, and as a result are “blind” in an area of their visual field, what is called a scotoma. Why do I put the word “blind” in quotation marks? It is because these blindsighted people claim that they don’t see any stimulus in a certain area of their visual field, and there is no reason to believe that they are fabricating, but when asked to guess as to whether a stimulus is present or about specific features of the stimulus, such as whether it is an ‘X’ or an ‘O’, they do considerably better than chance. These blindsighted individuals still seem to have some sort of awareness - call it “sight” - in the area in which they are blind. The condition is therefore called “blindsight”. The cartoon above nicely illustrates the condition.
Some philosophers say that blindsighted people lack a certain type of consciousness, sometimes called phenomenal consciousness, of the objects presented to their visual fields. These philosophers say things like there is “nothing it is like for these people to see the objects” or “the objects don’t appear any way to them”. Some philosophers have suggested that non-human animals are like blindsighted people in that they are in some sense aware of what’s going on in their environments, but they aren’t phenomenally conscious of these events.
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