We climbed this hill. Each step up we could see farther, so of course we kept going. Now we’re at the top. Science has been at the top for a few centuries now. And we look out across the plain and we see this other tribe dancing around above the clouds, even higher than we are. Maybe it’s a mirage, maybe it’s a trick. Or maybe they just climbed a higher peak we can’t see because the clouds are blocking the view. So we head off to find out-but every step takes us downhill. No matter what direction we head, we can’t move off our peak without losing our vantage point. So we climb back up again. We’re trapped on a local maximum. But what if there is a higher peak out there, way across the plain?...