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1. Your thoughts are more powerful than you know.

Several years ago, I was walking in Central Park with a friend, and he said, "You're slowing down; you must be thinking about something." And I was. I started to walk faster, clearing my mind, but then not long after, he said, "Ah, you're thinking again." I realized that if my thoughts immediately affect my body, I should be careful about what I think. Now if I get angry, I ask myself why I feel that way. If I can find the source of my anger, I can turn that negative energy into something positive.

2. Changing the world is a lifelong mission.

John and I thought our bed-in for peace [in 1969] would transform things—we weren't patient at all. But now I know that you have to be. You can't always measure the effects of activist work; you just have to wish and pray that the message gets through. Luckily, I think most people are activists now—it's a very beautiful age, when we're starting to become more aware that we have to work together to make things better.

3. You have to face trouble head-on.

I don't think you should always stay calm in a tense situation, because you might not ever confront the problem. Maybe it's better to actually let yourself be tense—and find a solution. Every day there are new problems to solve, and I always ask myself, Am I doing my best? I have only one life, so I want to make sure it's a good one.

4. The process of making art is as valuable as the art itself.

Experiencing sadness and anger can make you feel more creative, and by being creative, you can get beyond your pain or negativity. People's reactions to my work aren't necessarily important—it's fine if they have different opinions. If their response is good, then I feel good, but what I create has to do more with myself. When I express myself, I feel free.

5 Happiness takes work.

After John passed away, my grief showed in my face. I knew that was not good for our son, Sean, so one day I looked in the mirror and tried to make myself smile. At first it looked made-up, and I thought, Ugh, will this be good enough? But with practice, it felt more natural, and eventually my whole body started to smile—I think that's how I saved myself.

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