What's the best advice you've ever gotten? Fortune posed that question to 25 prominent business people, civic leaders and celebrities. The answers run the gamut from marketing mantras to life philosophies. Here are excerpts from some of the responses that we liked:

"I can't remember who told me this, but I certainly didn't grow up knowing it, so I must have gotten this advice at Salomon Brothers in the 1970s. The advice was, first, always ask for the order, and second, when the customer says yes, stop talking."
Michael Bloomberg, Mayor of New York City, founder of Bloomberg LP

My boss at the time, then-Maj. Gen. Jack Galvin, said "I think you ought to look for an out-of-your intellectual comfort zone experience." So that's what I did.
Gen. David Petraeus, Commanding general, multinational force - Iraq

"My father was an absolutely wonderful human being. From him I learned to always assume positive intent. Whatever anybody says or does, assume positive intent. You will be amazed at how your whole approach to a person or problem becomes very different."
Indra Nooyi, Chairman and CEO, Pepsico

"Don't panic. It's from Hitchhiker's Guide to the Galaxy by Douglas Adams. You have to be wary of emotion clouding your decision-making process - and of making a decision that you'll later regret."
Elon Musk, Founder and CEO, SPACEX

"The best advice I ever got came from my mother, Estée Lauder: She believed that if you had something good to say, you should put it in writing. But if you had something bad to say, you should tell the person to his or her face."
Leonard Lauder, Chairman, The Estée Lauder Companies