How we see?

Every single living system has vision techniques.Thereby they can detect objects. But there is a question right there; how we can be sure this object is really what it looks like. Because context is everything. For example; when we see an orange point on different backgrounds, we can easily decide they are the same orange point or on the same background we can say they are different colors. Actually context makes illusions which we can think of the bugs of our visual system.There is a speech which is about these illusions by Beau Lotto.

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