Wilson Mizner (May 19, 1876 – April 3, 1933) was an American playwright, raconteur, and entrepreneur. His best-known plays are The Deep Purple, produced in 1910, and The Greyhound, produced in 1912. He was manager and co-owner of The Brown Derby restaurant in Los Angeles, California, and was affiliated with his brother, Addison Mizner, in a series of scams and misadventures that inspired Stephen Sondheim's Bounce!. Wilson Mizner is noted for many witty sayings such as, "Be nice to people on the way up because you'll meet the same people on the way down," and, "When you steal from one author, it's plagiarism; if you steal from many, it's research". Mizner has suffered the same fate as Dorothy Parker: both are vividly remembered today for their witty repartee rather than for specific literary works.

Interestingly, this same quote is often attributed to Jimmy Durante. As Durante always said, " I got a million of em"... perhaps some of them were borrowed.

"Be nice to people on the way up because you'll meet them on the way down."

Quoted by Stuart B. McIver, Dreamers, Schemers and Scalawags, Pineapple Press, Sarasota, Florida, 1994.

More Info: en.wikipedia.org