I agree completely - it is possible, so it was a bad analogy. A better one would be, if one were transported a thousand years back in time and declared the existence of, say, neutrons to the people of the day, with absolutely no means of demonstrating them.FWIW, it's always seemed to me that it would be pretty simple to provide a blind person with proof beyond reasonable doubt that colors exist. Give him two pencils, one which writes in red and is labeled "red" in Braille, the other which writes in blue and is labeled "blue," and some blank sheets of paper. The blind person is asked to choose one pencil (he can cover up the Braille labels so others can't tell which one he's using) and draw a simple shape like a triangle with it. When he shows the triangle written with the red pencil, the sighted person always says "that's red," and when he shows the one written with the blue pencil, the sighted person always says "that's blue." How is this possible, unless there is some quality of the writing, aside from its shape, which sighted people call "color"?
Said people would be justified in rejecting neutrons even though we know now that they exist.