I’ll admit this seems counter-intuitive; most of us would shout “I can’t see anything” when stumbling around in the pitch dark. But understanding blindness requires a bit more thought.

It does depend on the type of blindness; acquired blindness seems to leave patients with light rather than darkness: imagine a speaker with an unplugged Aux cable – you’ve heard that buzzing noise? If your optic nerve is severed, random signals are generated in much the same way, resulting in constant random dancing patterns of light. And of course, closing your eyes won’t make them go away, so darkness is in fact the one thing you never see.

If you are born blind though, the issue is a little different. With no concept of sight, individuals born blind lack a perception of light and darkness in the same way as humans lack a perception of magnetic fields, or the 5th dimension. It’s not ‘darkness’ in the way we might imagine; the best way to understand it is to ask yourself what you can ‘see’ behind you right now. We don’t see a large black blob everywhere outside our field of vision – we see nothing, and that’s just normal.

It’s probably different for each person who experiences blindness, but safe to say its a little different to putting on a blindfold.

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‘Another one of Mr Shaunak’s Little Bites of Science’
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Published by Aran Shaunak