Craig Newmark

Joanna Shields

Nelson Peltz

Former CEO, Capital Cities/ABC

I got two pieces of advice I have always remembered. The first was from my father, Charles E. Murphy, who was a justice of the New York State Supreme Court. It was a point about ethics. He said, “Doing the wrong thing is not worth the loss of one night’s good sleep.”

The other came from Benjamin Selekman, a Harvard Business School professor who taught labor relations. The last thing he said, at his last lecture to my class, was, “Here is something to remember for the rest of your life: Don’t spend your time on things you can’t control. Instead, spend your time thinking about what you can.”

Tina Fey

Actress; creator and star of 30 Rock

About 15 years ago, I saw an Oprah show where she said, “Always be the only person who can sign your checks.” At the time, I had no money. I was at Second City in Chicago. I came to New York in 1997 to work on Saturday Night Live. I realized I have no head for business. And it would have been very easy for me to let someone take control of my money – for me to say, “Here, sign my checks…whatever.” But that line from Oprah has always been a reminder. Today, as much as it makes me super sleepy, I have to pay a lot of attention when my business manager talks to me about money. He talks to me about taxes, and I get really, really sleepy. But I listen.

Tony Robbins

Performance coach

In 1979, when I was 19, I had all these people giving me conflicting advice. Jim Rohn, a personal-development speaker, said, ‘Tony, think about it this way. If your worst enemy drops sugar in your coffee, what’s going to happen to you? Nothing. But what if your best friend drops strychnine in your coffee? You’re dead. You have to stand guard at the door of your mind.” He was saying that the selection of [my friends and advisors] will matter more than anything else, and that you can’t take anybody’s approach as sacrosanct.

Leonard Lauder

Chairman, The Estée Lauder Companies

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.

I learned this lesson the hard way. I’m chairman of the Whitney Museum of American Art in New York, and several years ago, I was angry with one of my trustees. I wrote a letter and signed it. But then I decided not to send the letter, and left it on my desk over the weekend. The following Monday I was out of the office, when a temp saw the letter and mailed it. The trustee got very angry and resigned from the board. To this day, writing that letter is something that I regret.