An Epistemological Digression

I have been rereading Robert Pirsig's Zen and the Art of Motorcycle Maintenance. This passage really sticks with me:

After a while he says, "Do you believe in ghosts?"

"No," I say.

"Why not?"

"Because they are un-sci-en-ti-fic."

The way I say this makes John smile. "They contain no matter," I continue, "and have no energy and therefore, according to the laws of science, do not exist except in people’s minds."

The whiskey, the fatigue and the wind in the trees start mixing in my mind. "Of course," I add, "the laws of science contain no matter and have no energy either and therefore do not exist except in people’s minds. It’s best to be completely scientific about the whole thing and refuse to believe in either ghosts or the laws of science. That way you’re safe. That doesn’t leave you very much to believe in, but that’s scientific too."