This is green. This is red. And this is blue. But how can you tell that what you're seeing as blue is the exact same thing as what I see as blue? We've named the colors to give us a way to communicate and reference them, but in reality, there's no way of knowing that what you see is the same as what another person sees. Even with the small steps and the giant leaps we've made as a species, there is still a lot to learn about earth, life, and the human condition. There's still everything we don't know.
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