How does white milk come from a red cow?
Why doesn’t the sun fall down?
How is it that all rivers flow into the ocean without ever filling it?
These questions, which could have come from any child today, are from the Rig Veda, a 3000-year-old Hindu text—and wondering and questioning are surely much older still. Early Homo sapiens, endowed with the same cranial capacity as your Aunt Diane,1 had to be asking similar questions 125,000 years ago. And once oral language developed sufficiently to share these ...