How do you prove your shirt is red to a blind man?

Question

Oh, and he's born blind too.

So how do you prove your shirt is really red?

Wavelengths?

So tell me, if you're blind all your life, how do you tell a blue wavelength from a red wavelength?

Answer 1

You can't.

Answer 2

You can set up a frequency-detector to a computer that outputs the results audibly rather than visually. In fact, you could get the blind man to do this (then he wouldn't mistrust the equipment). Then, just detect the frequencies being emitted from the shirt. From that, the blind man will be happy that the shirt is most reflective to a red colour.#

Edit: A blind person can still tell when one number is bigger than the other!

Answer 3

If we both agree that 'red' constitutes a certain range of wavelengths of light then all you need to do is analyse the colour of the shirt and produce an output in a form that the blind man can detect, e.g. braille. He won't have the 'experience' of red but then we all have a different experience anyway, so that hardly matters.

Answer 4

You would do it the same way you would teach some one about God. You could only start if they had a desire to know. If they don't care then the only thing you can do is to try to find a way to help them to care. in the case of the shirt, I wouldn't worry about it. What we call a color is all a matter of perspective. But no matter what or perspective may be it cannot change what the properties of that color are.

Answer 5

Easy. Bounce light off it, measure the wavelength, describe the spectrum to him, and print it all out in braille for good measure.

EDIT: Blue wavelengths are shorter than red wavelengths. It's the basic definition of color, and easily graspable even if you can't see it - which is how we know about other forms of light, like microwaves and gamma rays.

Answer 6

You can't. He is blind and cannot see so he will have to trust you and believe you because he has faith in you. That is the only way I can possibly think of to convince him my shirt is red.

Answer 7

Colors are determined by the way our brains interperate light of a certain spectrum bouncing off of matter. He'd have no perception of color, so:
A. He'd have to learn what red IS first,
and B. In a sense, it's NOT red.

The color is only determined by what the majority see it as.

Democracy?

Answer 8

The blind man would have to have a spectral analyzer with a braille readout. Either that, or a reliable witness.

Answer 9

The shirt is only red to those who can see it. To those who can't, there isn't a shirt at all.

Answer 10

you cannot prove the shirt is red
as i said before
the blind man may understand what red is ... but he cannot know for sure that the shirt is red through words you tell him
someone else may tell him the shirt is pink or brown

Answer 11

I don't think a blind man is worried about what color his shirt is.