My previous post was defending philosophy against objections from Neil deGrasse Tyson. I argued that scientific observation was no more sure or more important than philosophical argument.

Enter #thedress.

The world is now divided on whether this dress is blue and black or white and gold. I’ve actually seen it as both, even in the same picture. Vox goes into the science here. I won’t get too into that, but I highly suggest you read it. As a philosopher, I want to raise a philosophical question. Can we ever trust our observations?

We’re all familiar with seeing the same thing as two different colors (are these navy pants really black?) And eyesight isn’t the only problem. Have you ever heard of phantom limb syndrome? For people who have a limb amputated, many continue to feel sensations, pain or itching, in the place where the limb used to be. And surely you’ve felt bugs “crawling all over your skin” when there were no such bugs. Some people also hear voices. There are no voices, of course, and maybe the person is schizophrenic, but that doesn’t make the sensation any less real for that person.

And we’ve all pondered whether this is reality or the Matrix, am I right?

But the problem runs deeper. Science has shown us that observation itself changes reality. That is, a thing may behave in one way, but then when it’s being observed, it behaves in a different way. There’s a cute little cartoon explaining the phenomenon here:

It’s called the “double slit experiment,” and it shows that light particles change their behavior when being watched. The very act of observing may forever prevent us from having certain knowledge of the nature of reality.

Observation of the natural world must be filtered through our senses. But so long as our senses mislead us at best, fail us at worst, then how can we be certain about anything?

Well, as Descartes famously said, we can be certain of one thing, “I think, therefore I am.” I think we can also be certain of the rules of logic. And this is the philosopher’s wheelhouse. While people like Tyson say we’re just bickering about “the meaning of meaning,” I say we’ve spent centuries building up a foundation for knowledge. That foundation surely cannot be sensory observation. That foundation cannot be science. We should begin with philosophy.