"One of your partners, named Mr Market, is very obliging indeed. Every day he tells you what he thinks your interest is worth and, furthermore, offers to buy you out or sell you an additional interest on that basis. Sometimes his idea of value appears plausible and justified by business developments and prospects as you know them. Often, on the other hand, Mr Market let his enthusiasm or his fears run away from him, and the value he proposes to you seems to you little short of silly"
---Ben Graham