9 Hilarious and Inspiring Quotes From Talk-Show Extraordinaire David Letterman To celebrate his birthday, check out these witty quotes from the famous comedian.

By Rose Leadem

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David Letterman

Talk-show host extraordinaire David Letterman has one or two things up his sleeve to teach you. After 33 years hosting The Late Night Show With David Letterman and becoming the longest-serving late night talk-show host yet, he walked away with not only a number of awards but lessons, too. And the good news is he's back.

After leaving his talk show in 2015, Letterman recently returned with a talk show series on Netflix, My Next Guest Needs No Introduction, interviewing major influential names like President Obama, George Clooney and Malala Yousafzai.

Related: 50 Inspirational Quotes to Motivate You

Through his work, Letterman has made major social and political impacts and has inspired the likes of Conan O'Brien, Stephen Colbert, Jimmy Kimmel and other talk show celebrities following in his footsteps. With his own production company, Worldwide Pants, which is behind hit sitcom Everybody Loves Raymond, it's safe to say he's made a name for himself both on and off the camera. And the comedian, entrepreneur and celebrity can teach you a number of things on subjects like courage, motivation and happiness.

Related: 17 Inspirational Quotes from Oscar-Winning Movies

To learn more, here are nine inspiring quotes from David Letterman.

On courage

"There's only one requirement of any of us, and that is to be courageous. Because courage, as you might know, defines all other human behavior. And, I believe -- because I've done a little of this myself -- pretending to be courageous is just as good as the real thing." -- David Letterman

On motivation

"Sometimes something worth doing is worth overdoing." -- David Letterman

On impact

"I'm just trying to make a smudge on the collective unconscious." -- David Letterman

Related: 20 Motivational Quotes to Inspire Your Next Business Idea

On ideas

"Next in importance to having a good aim is to recognize when to pull the trigger." -- David Letterman

On happiness

"I have found that the only thing that does bring you happiness is doing something good for somebody who is incapable of doing it for themselves." -- David Letterman

On fear

"My greatest fear in life is being dull. You can be great, you can be awful, but just don't bother being dull." -- David Letterman

On attitude

"The worst-tempered people I have ever met were those who knew that they were wrong." -- David Letterman

Related: 50 Inspirational Quotes to Help You Achieve Your Goals

On purpose

"Everyone has a purpose in life. Perhaps yours is watching television." -- David Letterman

On mindset

"I wish I hadn't been so gosh darn single-minded. Because when your focus is that tight, you miss a lot of what's going on around you." -- David Letterman

Rose Leadem is a freelance writer for Entrepreneur.com. 

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