Smith, Adam

"The real price of everything is the toil and trouble of acquiring it."

"What can be added to the happiness of a man who is in health, out of debt, and has a clear conscience?"

"Science is the great antidote to the poison of enthusiasm and superstition."

"Labour was the first price, the original purchase-money that was paid for all things. It was not by gold or by silver, but by labour, that all wealth of the world was originally purchased."

"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." - The Wealth of Nations