I grew up with my identical twin, who was an incredibly loving brother. Now, one thing about being a twin is that it makes you an expert at spotting favoritism. If his cookie was even slightly bigger than my cookie, I had questions. And clearly, I wasn't starving.

　　When I became a psychologist, I began to notice favoritism of a different kind, and that is how much more we value the body than we do the mind. I spent nine years at university earning my doctorate in psychology, and I can't tell you how many people look at my business card and say, "Oh, a psychologist. So not a real doctor," as if it should say that on my card. (Laughter) This favoritism we show the body over the mind, I see it everywhere.

　　I recently was at a friend's house, and their five-year-old was getting ready for bed. He was standing on a stool by the sink brushing his teeth, when he slipped, and scratched his leg on the stool when he fell. He cried for a minute, but then he got back up, got back on the stool, and reached out for a box of Band-Aids to put one on his cut. Now, this kid could barely tie his shoelaces, but he knew you have to cover a cut, so it doesn't become infected, and you have to care for your teeth by brushing twice a day. We all know how to maintain our physical health and how to practice dental hygiene, right? We've known it since we were five years old. But what do we know about maintaining our psychological health? Well, nothing. What do we teach our children about emotional hygiene? Nothing. How is it that we spend more time taking care of our teeth than we do our minds. Why is it that our physical health is so much more important to us than our psychological health?

　　We sustain psychological injuries even more often than we do physical ones, injuries like failure or rejection or loneliness. And they can also get worse if we ignore them, and they can impact our lives in dramatic ways. And yet, even though there are scientifically proven techniques we could use to treat these kinds of psychological injuries, we don't. It doesn't even occur to us that we should. "Oh, you're feeling depressed? Just shake it off; it's all in your head." Can you imagine saying that to somebody with a broken leg: "Oh, just walk it off; it's all in your leg." (Laughter) It is time we closed the gap between our physical and our psychological health. It's time we made them more equal, more like twins.

　　Speaking of which, my brother is also a psychologist. So he's not a real doctor, either. (Laughter) We didn't study together, though. In fact, the hardest thing I've ever done in my life is move across the Atlantic to New York City to get my doctorate in psychology. We were apart then for the first time in our lives, and the separation was brutal for both of us. But while he remained among family and friends, I was alone in a new country. We missed each other terribly, but international phone calls were really expensive then and we could only afford to speak for five minutes a week. When our birthday rolled around, it was the first we wouldn't be spending together. We decide to splurge, and that week we would talk for 10 minutes. I spent the morning pacing around my room, waiting for him to call -- and waiting and waiting, but the phone didn't ring. Given the time difference, I assumed, "Ok, he's out with friends, he will call later." There were no cell phones then. But he didn't. And I began to realize that after being away for over 10 months, he no longer missed me the way I missed him. I knew he would call in the morning, but that night was one of the saddest and longest nights of my life. I woke up the next morning. I glanced down at the phone, and I realized I had kicked it off the hook when pacing the day before. I stumbled out off bed, I put the phone back on the receiver, and it rang a second later, and it was my brother, and, boy, was he pissed. (Laughter) It was the saddest and longest night of his life as well. Now I tried to explain what happened, but he said, "I don't understand. If you saw I wasn't calling you, why didn't you just pick up the phone and call me?" He was right. Why didn't I call him? I didn't have an answer then, but I do today, and it's a simple one: loneliness.

　　Loneliness creates a deep psychological wound, one that distorts our perceptions and scrambles our thinking. It makes us believe that those around us care much less than they actually do. It make us really afraid to reach out, because why set yourself up for rejection and heartache when your heart is already aching more than you can stand? I was in the grips of real loneliness back then, but I was surrounded by people all day, so it never occurred to me. But loneliness is defined purely subjectively. It depends solely on whether you feel emotionally or socially disconnected from those around you. And I did. There is a lot of research on loneliness, and all of it is horrifying. Loneliness won't just make you miserable, it will kill you. I'm not kidding. Chronic loneliness increases your likelihood of an early death by 14 percent. Loneliness causes high blood pressure, high cholesterol. It even suppress the functioning of your immune system, making you vulnerable to all kinds of illnesses and diseases. In fact, scientists have concluded that taken together, chronic loneliness poses as significant a risk for your longterm health and longevity as cigarette smoking. Now cigarette packs come with warnings saying, "This could kill you." But loneliness doesn't. And that's why it's so important that we prioritize our psychological health, that we practice emotional hygiene. Because you can't treat a psychological wound if you don't even know you're injured. Loneliness isn't the only psychological wound that distorts our perceptions and misleads us.

　　情感上的急救

　　Failure does that as well. I once visited a day care center, where I saw three toddlers play with identical plastic toys. You had to slide the red button, and a cute doggie would pop out. One little girl tried pulling the purple button, then pushing it, and then she just sat back and looked at the box, with her lower lip trembling. The little boy next to her watched this happen, then turned to his box and and burst into tears without even touching it. Meanwhile, another little girl tried everything she could think of until she slid the red button, the cute doggie popped out, and she squealed with delight. So three toddlers with identical plastic toys, but with very different reactions to failure. The first two toddlers were perfectly capable of sliding a red button. The only thing that prevented them from succeeding was that their mind tricked them into believing they could not. Now, adults get tricked this way as well, all the time. In fact, we all have a default set of feelings and beliefs that gets triggered whenever we encounter frustrations and setbacks.

　　Are you aware of how your mind reacts to failure? You need to be. Because if your mind tries to convince you you're incapable of something and you believe it, then like those two toddlers, you'll begin to feel helpless and you'll stop trying too soon, or you won't even try at all. And then you'll be even more convinced you can't succeed. You see, that's why so many people function below their actual potential. Because somewhere along the way, sometimes a single failure convinced them that they couldn't succeed, and they believed it.

　　Once we become convinced of something, it's very difficult to change our mind. I learned that lesson the hard way when I was a teenager with my brother. We were driving with friends down a dark road at night, when a police car stopped us. There had been a robbery in the area and they were looking for suspects. The officer approached the car, and he shined his flashlight on the driver, then on my brother in the front seat, and then on me. And his eyes opened wide and he said, "Where have I seen your face before?" (Laughter) And I said, "In the front seat." (Laughter) But that made no sense to him whatsoever. So now he thought I was on drugs. (Laughter) So he drags me out of the car, he searches me, he marches me over to the police car, and only when he verified I didn't have a police record, could I show him I had a twin in the front seat. But even as we were driving away, you could see by the look on his face he was convinced that I was getting away with something.

　　Our mind is hard to change once we become convinced. So it might be very natural to feel demoralized and defeated after you fail. But you cannot allow yourself to become convinced you can't succeed. You have to fight feelings of helplessness. You have to gain control over the situation. And you have to break this kind of negative cycle before it begins. Our minds and our feelings, they're not the trustworthy friends we thought they were. They are more like a really moody friend, who can be totally supportive one minute, and really unpleasant the next. I once worked with this woman who after 20 years marriage and an extremely ugly divorce, was finally ready for her first date. She had met this guy online, and he seemed nice and he seemed successful, and most importantly, he seemed really into her. So she was very excited, she bought a new dress, and they met at an upscale New York City bar for a drink. Ten minutes into the date, the man stands up and says, "I'm not interested," and walks out. Rejection is extremely painful. The woman was so hurt she couldn't move. All she could do was call a friend. Here's what the friend said: "Well, what do you expect? You have big hips, you have nothing interesting to say, why would a handsome, successful man like that ever go out with a loser like you?" Shocking, right, that a friend could be so cruel? But it would be much less shocking if I told you it wasn't the friend who said that. It's what the woman said to herself. And that's something we all do, especially after a rejection. We all start thinking of all our faults and all our shortcomings, what we wish we were, what we wish we weren't, we call ourselves names. Maybe not as harshly, but we all do it. And it's interesting that we do, because our self-esteem is already hurting. Why would we want to go and damage it even further? We wouldn't make a physical injury worse on purpose. You wouldn't get a cut on your arm and decide, "Oh, I know! I'm going to take a knife and see how much deeper I can make it."

　　But we do that with psychological injuries all the time. Why? Because of poor emotional hygiene. Because we don't prioritize our psychological health. We know from dozens of studies that when your self-esteem is lower, you are more vulnerable to stress and to anxiety, that failures and rejections hurt more and it takes longer to recover from them. So when you get rejected, the first thing you should be doing is to revive your self-esteem, not join Fight Club and beat it into a pulp. When you're in emotional pain, treat yourself with the same compassion you would expect from a truly good friend. We have to catch our unhealthy psychological habits and change them. One of unhealthiest and most common is called rumination. To ruminate means to chew over. It's when your boss yells at you, or your professor makes you feel stupid in class, or you have big fight with a friend and you just can't stop replaying the scene in your head for days, sometimes for weeks on end. Ruminating about upsetting events in this way can easily become a habit, and it's a very costly one. Because by spending so much time focused on upsetting and negative thoughts, you are actually putting yourself at significant risk for developing clinical depression, alcoholism, eating disorders, and even cardiovascular disease.

　　The problem is the urge to ruminate can feel really strong and really important, so it's a difficult habit to stop. I know this for a fact, because a little over a year ago, I developed the habit myself. You see, my twin brother was diagnosed with stage III non-Hodgkin's lymphoma. His cancer was extremly aggressive. He had visible tumors all over his body. And he had to start a harsh course of chemotherapy. And I couldn't stop thinking about what he was going through. I couldn't stop thinking about how much he was suffering, even though he never complained, not once. He had this incredibly positive attitude. His psychological health was amazing. I was physically healthy, but psychologically I was a mess. But I knew what to do. Studies tell us that even a two-minute distraction is sufficient to break the urge to ruminate in that moment. And so each time I had a worrying, upsetting, negative thought, I forced myself to concentrate on something else until the urge passed. And within one week, my whole outlook changed and became more positive and more hopeful. Nine weeks after he started chemotherapy, my brother had a CAT scan, and I was by his side when he got the results. All the tumors were gone. He still had three more rounds of chemotherapy to go, but we knew he would recover. This picture was taken two weeks ago.

　　By taking action when you're lonely, by changing your responses to failure, by protecting your self-esteem, by battling negative thinking, you won't just heal your psychological wounds, you will build emotional resilience, you will thrive. A hundred years ago, people began practicing personal hygiene, and life expectancy rates rose by over 50 percent in just a matter of decades. I believe our quality of life could rise just as dramatically if we all began practicing emotional hygiene.

　　Can you imagine what the world would be like if everyone was psychologically healthier? If there were less loneliness and less depression? If people knew how to overcome failure? If they felt better about themselves and more empowered? If they were happier and more fulfilled? I can, because that's the world I want to live in, and that's the world my brother wants to live in as well. And if you just become informed and change a few simple habits, well, that's the world we can all live in.

　　Thank you very much.