Now, assuming we had the ability to speak with dogs (yes, I know, some of you swear that you already can!), we could never get a dog to grasp the notion of the color red. We couldn’t describe it sufficiently for the dog to understand it because we could only reference colors that the dog sees, and any other color is “unimaginable” to a dog. Consequently, a dog could never fully grasp “red”.

Butterflies have four sets of cones. Hmmm. Now, I wonder, what colors does a butterfly see that you and I can’t even imagine? Is there a color that accompanies the sound of a bird chirping? Is there a color to the scent of a rose? Whatever those colors are that a butterfly sees, we can’t grasp them because we have nothing to compare them to. If we try to imagine those colors based on our visual experience, we are only coming up with some version of what we already know, no matter how extreme it may be. If we can imagine it, in any form, then we could see it. And since we can't see it, then it defies our most extraordinary imaginations.

It isn't that these "butterfly visible" colors don't exist for us humans. They are everywhere, completely surrounding us all the time. The simple fact that we can't see them doesn't mean they don't exist. But it does give pause, doesn't it? How much of the vast, miraculous universe do we ignore just because we can't see it? How much of "reality" is missed entirely because it doesn't show up on our visual cortex?

You could say that, in order to imagine what colors a butterfly sees, if such were even possible, we would have to get outside of our understanding of color. Now that’s a dilemma. How do you think about something that is outside of all the rules of thinking you can imagine?

Well, now. THAT'S a question worth pondering. Have at it.