If you’re born blind then you don’t have any understanding of sight. The best analogy is to try and imagine seeing through your elbow. Colour has no meaning and neither does anything else to do with sight. This means that you can’t dream in pictures because you’ve never seen one.
If you go blind it’s different, you can still remember colours and images from the past so you can dream about those. But you can’t see anything new so if it’s described to you then you imagine it using images from the past. Or so I understand anyway.
What a good question! When a person hasn’t got a sense like hearing or sight, it is often the case that the other senses get better to sort of fill the gap, and help compensate. For instance, many blind people have excellent hearing, and with the aid of a special walking stick, can detect the surface in front of them by sweeping it back and forth as they walk. Maybe blind people who have always been blind don’t dream in pictures (see answers below), but they might have dreams with amazing and wonderful sound. I don’t know any blind people to ask – do you?
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