speculation and the asset bubble

Every so often the price of something — tulips, internet stocks, houses, a cryptocurrency — soars far beyond any sensible estimate of its worth, then suddenly collapses, ruining latecomers. This boom-and-bust pattern is an asset bubble, and the behaviour that inflates it is speculation: buying an asset not for the income or use it provides, but purely in the hope of selling it later to someone else at a higher price.

A bubble grows on a self-reinforcing loop. Prices rise, which attracts buyers hoping for more gains, whose buying pushes prices higher still, which seems to prove the optimists right and draws in yet more buyers. Reasonable valuation gets abandoned; people buy simply because prices are going up. The dark logic underneath is the greater fool theory: you knowingly overpay, betting a 'greater fool' will pay even more later. But the supply of greater fools is finite. At some point confidence cracks, everyone rushes for the exit at once, and the price crashes far faster than it rose. The famous early case is the Dutch tulip mania of the 1630s, when single bulbs briefly traded for the price of a house.

Speculation in moderation is normal and even useful — it adds liquidity and helps prices reflect expectations. But bubbles do real economic damage. They misdirect capital into the wrong things (too many fibre-optic cables in 2000, too many houses in 2006), and when they burst they can wipe out savings, topple banks that lent against inflated collateral, and tip the whole economy into recession, as the 2008 housing crash did. The hard, honest truth is that bubbles are far easier to identify after they pop than to call with confidence while they are still inflating.