“What good do you think it does to waller all over a horse thataway? said Rawlins.
I dont know, said John Grady. I aint a horse.”
All the Pretty Horses (1992)
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Cormac McCarthy 270
American novelist, playwright, and screenwriter 1933Related quotes

“If I had asked people what they wanted, they would have said faster horses.”
Patrick Vlaskovits, " Henry Ford, Innovation, and That “Faster Horse” Quote https://hbr.org/2011/08/henry-ford-never-said-the-fast," in Harvard Business Review, August 29, 2011.
Misattributed

“You think about all that stuff that can happen to you, he said. There aint no end to it.”
All the Pretty Horses (1992)

Though research done for Wikiquote indicates that the attribution of this remark to Hugo seems extensive on the internet, no source has been identified. It seems to be a statement a modern satirist might make, derived from one made circa 1910 by Mrs Patrick Campbell regarding homosexuals: "Does it really matter what these affectionate people do — so long as they don’t do it in the streets and frighten the horses?"
Disputed

Ronald Coase in speech to the "International Society of New Institutional Economics" the 17 September 1999, Washington DC. He claims he was quoting fellow economist Ely Devons which reportedly said this in a meeting
1990s and later