The hardest questions in the world always seem to be the most fun to take a crack at. It's the seemingly impossible ones that get called upon again and again by everybody and their mothers because it's fun to explore what you don't know. It's fun to think that you might be able to figure out the world's most pressing questions: Where did your leftovers go? Why don't super foods give you super powers? What does happen when you give a mouse a cookie?

I know you're hiding something behind those whiskers...

And then there's this one: How do you teach a person who's been blind their whole life about color? How can you describe something that you've just known from day one? I was thinking about this the other night on my walk down Viale di Trastevere in Rome, where the apartments differ in the color of their exteriors wherever you look. So here's my crack at the question:

Note: I am operating under the assumption that the person I will be writing to has been blind their entire life and has operated with all of their other senses unhindered throughout their life.

So, what is color? I would guess that some people have thought it hard to explain it to you because you don't have an experience to compare with it. But I beg to differ.

Think back to the last time you were eating a meal. Now remember the taste of whatever you were eating. If you had two dishes or even two different flavors contained in this meal, think about one, then the other.

Now recall the smell of the air where you were eating this meal - or maybe even the feeling that you got when you smelled the air. Now take a deep breath of the air you're breathing right now. I would guess that there's a difference between the two of those smells, right?

You can do the same thing with the texture of your shirt versus the texture of your pants, or the sound of cars driving by versus the sound of wind finding its way through the branches of trees in a forest.

These are your colors; these are the sensations that you get from experiencing something and then experiencing another. One is different from the other and is, therefore, a "color". What are colors but words given to a sensation that people find when they experience pieces of life through their eyes?

We have different words to show a different experience with a "color" -- to communicate with others who have experienced color as to share the experience. It's the differences that people see in these colors that warrant a name being given to them. So when you use any other sense to experience the world around you, you are discovering and using your colors in the coarse grain of concrete or the threads of a soft blanket. When looking for differences within a category of a color, people might call something a "shade" or "hue"; this is when a song changes the key ever-so-slightly in the background so that the sound of the whole song takes on a different feeling at that moment, or when the barbecue sauce you're using varies just a bit from your normal sauce because of the smokey after-taste.

For this reason, trying to explain individual colors to you wouldn't really help you learn about color as a whole, either. The experience that somebody defines a specific color or shade or hue from is different from how somebody else would do it. When thinking of the color green, I may describe it as healthy, comfortable and the feeling of laying in grass; somebody else may describe it as sick, uneasy and the feeling of over-sensitive skin stretched over their body.

My point is, the only part of knowing about visual colors that you haven't already experienced is the sensation of color, itself. You don't need to process light to experience colors. You've navigated the world with your own senses and experiencing the sensations that come with them. Within those experiences, you already have the foundation to understand something that you haven't experienced, yourself. I just ask that you leave your mind open to figuring it out and accept that you'll never completely know what it means to see color, but I think you'll be able to understand it.