While it's always good to elevate evidence-based knowledge above "woo" or "belief", it's not healthy to close your mind off completely against anything that isn't currently proven. We might know that we don't know a lot of things, but the most interesting thought experiments happen in the area that concerns the things we don't know that we don't know.

When an engineer tells me he built a car that runs on water, he'd better bring some pretty amazing evidence. And no, I'm not going to waste time reading his paper looking for the inevitable flaw, either.

I've heard "evidence" of aliens my entire life. Guess how many panned out. Zero. But that never seems to discourage anyone from believing that an artifact on a photo must have the most implausible explanation ever - aliens!

Where do you draw the line? Time travel? Teleportation? Astrology? Fortune tellers? Razor blade sharpening? Reincarnation?