In the late 1990s and early 2000s the idea that homes and apartments were spectacular investments gained a stronghold on the public imagination in the United States and in many other countries, as well. Not only did prices go up, but there was palpable excitement about real estate investment. […] It appears that people had acquired a strong intuitive feeling that home prices everywhere can only go up. They seemed really sure of this, so much so that they were ready to dismiss any economist who said otherwise. If pressed for an explanation, they typically said that, because there is only so much land, real estate prices have always gone up. Population pressures and economic growth should inevitably push real estate prices strongly upward. These arguments are demonstrably false. But no matter. […] The appeal of the argument means that it tends to be attached to stories about real estate booms, and it spreads by word of mouth, feeding the boom. The contagion of the argument for ever-increasing home prices during a boom is enhanced by the intuition behind it. 

From George Akerlof and Robert Shiller’s Animal Spirits: How Human Psychology Drives the Economy, and Why It Matters for Global Capitalism, Princeton, New Jersey: Princeton University Press, 2009, pp. 149-151.