Something I learned in high school history has come back unexpectedly while I’ve been brooding about Jonathan Rees’ opposition to MOOCs and his views on what they threaten. A couple of miles away from the place where I grew up is this beautiful Iron Age hill fort: Within the inner circle are the remaining stone foundations of an original castle, and—critically—the well that stored water for the whole settlement. Soldiers controlled the resources in the middle, and the villagers and…