I doubt that we have the same vision of colors!
I mean, may be the color i see it as red, is the color you see it as green, but in case you have called this color as "red" from the begening, so you call it red, too!
So when we talk together, we do not face a paradox, because all of us have called that color as red
Or white, or green
The question is, what proves that we all are seeing the same color?