Variant: When you sell a man a book you don’t sell him just twelve ounces of paper and ink and glue - you sell him a whole new life. Love and friendship and humour and ships at sea by night - there’s all heaven and earth in a book, a real book I mean.
Source: Parnassus on Wheels
1970s, The Education of Mike McManus, TVOntario, December 28 1977
In Star Science Fiction 5, edited by Frederik Pohl, p. 53
Short fiction, Company Store (1959)
“I told him that his profit is made when you buy, not when you sell.”
Rich Dad Poor Dad: What the Rich Teach Their Kids About Money-That the Poor and the Middle Class Do Not!
Attributed to Marx (possibly in jest) in W. C. Privy's Original Bathroom Companion (2003).
Misattributed
Source: Nickel and Dimed: On (Not) Getting By in America
Source: The Greening of America (1970), Chapter VII : "It's Just Like Living", p. 162
“When a man is trying to sell you something, don't imagine he is that polite all the time.”
Country Town Sayings (1911), p34.
