A century ago the Spanish flu confounded scientists and devastated whole regions, but while today's society has air travel and an enormous, heterogeneous population, we also have antibiotics, fantastic communication networks and, perhaps most crucially, more data than ever.

Memory's truth, because memory has its own special kind. It selects, eliminates, alters, exaggerates, minimizes, glorifies, and vilifies also; but in the end it creates its own reality, its heterogeneous but usually coherent version of events; and no sane human being ever trusts someone else's version more than his own.