Asset inflation often produces something called "wealth illusion," the belief that pricier asset holdings necessarily make one permanently richer. Illusions are dangerous. Eventually, painful reality intervenes. The "wealth illusion" of asset inflation is seductive, which is why central banks in charge of a fiat currency and subject to no external disciplines so often drift in that direction. Politicians smile in satisfaction and powerful Washington lobbies cry for more.  But an economy built on an illusion is hardly a sound structure. We may be doomed to learn that lesson once again before long.