看见 - refers to perceiving or seeing in itself 看到 - refers to the successful act of seeing something, implying that there is the possibility of not seeing it. (到 implies reaching out and attaining something) They sound frightfully similar, don't they?

区别：看见指视觉 = see。看到指视觉和注意力两者= see & notice

I'm not an expert but I think the difference between the two is a bit clearer if you consider the negative forms of these. Depending on the context, 他看不见 could mean "He is unable to see" and I think these are the words you would use to describe a blind man. 他看不到 is more like "He didn't see (some specific thing)." His failure to see it has nothing to do with his capacity for sight.

Nothing actually difference here. I think it is just a usage different from different people as they usually do. I guess it just like when someone asks "how are you?" and you might reply with words "Fine/Nice/Good." Is there any difference? :D But the sentence "你看了吗?" is definitely different from "你看见了吗" and "你看到了吗?" It means "Have you seen it yet?"

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