Tom Shadyac was the hugely successful Hollywood director of such films as Liar Liar, The Nutty Professor, Bruce Almighty and Patch Adams. Then in 2007 he moved out of his 17,000-foot mansion and into—surprise!—a mobile home. He began giving away his income. The luxuries of his former lifestyle had taught him one thing: "I was no happier," he says. Not long after, he was hit on the head during a bike accident and suffered from debilitating post-concussion syndrome. This last physical struggle gave him the courage to talk about why he made such a drastic change as well as the courage to direct the recently released small-budget documentary I Am, which examines the troubling question, What's wrong with our world—and what can we do about?

He participated in Oprah's Lifeclass on "Newton's Third Law," and we asked him to talk with us a little further about the topic. What resulted were some life-changing ideas for all of us:

Newton's third law [of motion] or karma—however each of us chooses to name it—is something I've been aware of for years. I call it cause and effect: The energy that you put into the world comes back. In other words, the fruit is in the seed. You can't sow an apple seed and expect to get an avocado tree. The consequences of your life are sown in what you do and how you behave.

Our culture does not teach us this, but what happens in Vegas does not stay in Vegas. If you cheat in Vegas, it comes right home with you. If you cheat in Vegas, you walk home as a cheater. You lie awake at a night a cheater. You cannot escape it.

The one thing that advances a society is not technology or so-called development; it's love—that one principle.

I'm not a big fan of this idea of bad karma, saying someone got sick because of bad karma. She may very well have gotten sick because of good karma. I know my accident, facing my own death, was a perfect blessing.

Often, when people say, "I have a karma problem," they really have a perspective problem. They think they are in a karma rut because they are not getting what they want. I think people have to move from the "wish" to the "willing." What I mean is, move from "I wish I could have this" to the willingness to accept what is. For now. It's just for now.

We've got to remove our boxes around the self. It doesn't work that way. There is no "I." That's an illusion we've got to get beyond.

Next: What's the "goal" of karma?

We are all responsible for our own causes and the energy we put into the world. But our actions and reactions are intertwined, so my greed and selfishness may very well be creating a lack in someone else.

It's not up to us to judge the karma of anyone else. It's up to us to clean up our energy and our own karma and leave the results to the higher power that created this whole flipping thing.

Science is now proving that altruism is why we're still here, that empathy is in our biology. Humanity is not just survival of the fittest but a cooperative enterprise. We miss that story. Every time you get in your car to go home, you don't understand or appreciate the thousands of cooperative acts involved in just getting you home: the fact that someone had to build a car to certain specifications because we've agreed what safety standards are. Someone riding next to you has agreed to follow the speed limit. You had that car registered, and you stop at traffic lights. It's a huge, long list of cooperation. But what we see is the guy who stole the car—that's what gets on the news at night.

We cannot go on like this, the way we treat each other, the way we look at life, the world economy, the way we think of things. The pain will come because if we sow a seed of separation, division, and disunity and disharmony, that is exactly the fruit we'll get.

When you do a loving thing, when you put out positive energy, you feel happy. This is how human beings are wired. So the goal of karma—if there is a goal—is not to put out positive energy in order to get some positive energy back. The goal is to put out positive energy and feel positive about your life. That's where the work is. That's why the true revolution is a personal revolution.

We're all in this together. I sure as hell believe it.

More on Positive Energy

• Martha Beck on knowing when to walk away
• The energy makeover