If you type the above line in Google, you can see 1000s of article about it. Coz. people wanna live longer, healthier, and happier. Both of these things come from positive thinking. There are many researches reports and books about this.
Sometimes I feel that I am not a positive thinker. I don't know why, I see the negative aspect of the matter first. I wanna change my attitude and behavior. So, I am planning to search a good book about positive thinking. Although, I read few books, not exactly the title 'positive thinking', but books like 'How to make people like you in 90 seconds or less', 'How to win friends and influence people', 'You can win' etc.
Let's work out for the positive changes in negative thinking.