People of the same trade seldom meet together, even for merriment and diversion, but the conversation ends in a conspiracy against the public, or in some contrivance to raise prices.
Source: The Wealth of Nations, vol. 1, bk. 1, ch. 10, 1776.
-- Adam Smith, (Jun 5 1723-1790), Scottish economist; He laid the foundation for classical economics with An Inquiry into the Nature and Causes of the Wealth of Nations, 1776.