In particular, our ability to permanently alter the land — whether with bulldozers, explosives, fertilizer or dumping — is exponentially greater than it was when the basics of our property law system were created. The amount of change a single person can do now to a piece of land in a day would have required an army of people in 1500. The consequences of this difference between then and now are quite profound, and tomorrow I shall relate a little impromptu fable to illustrate why. S.E. Harrison is the author of “Plutonomics: A Unified Theory of Wealth”. http:// plutonomics, wordpress.com.