Quotes Uncovered: Who First Thought the Grass Was Greener?

Nineteen weeks ago I invited readers to submit quotations for which they wanted me to try to trace the origins, using The Yale Book of Quotations and more recent research by me. Hundreds of people have responded via comments or e-mails. I am responding as best I can, a few per week.

Steve Long asked who said this quote:

Trust everybody. But cut the cards.

The Yale Book of Quotations, which attempts to trace all famous quotations to their earliest occurrences, has the following:

“Thrust ivrybody — but cut th’ ca-ards.” Finley Peter Dunne, Mr. Dooley‘s Philosophy (1900).

huth asked:

The grass is always greener on the other side.

The YBQ lists this as a proverb, citing as the earliest example of the wording above in the Chicago Tribune, August 28, 1923, but also noting that Ovid, in Ars Amatoria, used a Latin expression translating as “The harvest is always more fruitful in another man’s fields.”
Andrew asked:

Who said “Put all of your eggs in one basket, and watch that basket”? I have seen it attributed to Mark Twain and Andrew Carnegie.

According to The Yale Book of Quotations:

“Don’t put all your eggs in one basket” is all wrong. I tell you “put all your eggs in one basket, and then watch that basket.” Andrew Carnegie, address to students at Curry Commercial College, Pittsburgh, Pa., June 23, 1885. Printed in Carnegie’s book, The Empire of Business (1902).

The quotation is almost universally attributed to Mark Twain, but Twain’s usage was later, and he probably picked it up from Carnegie.
Do any readers have any other quotations whose origins they would like me to attempt to trace?