As A Man Thinketh is an inspirational self-help book written by James Allen. In this book, Allen tells about how the power of one's thoughts can give power over one's life. Allen lays the idea that people are the outcome of their thought. A small thought that seeds within can change the action of a person, and prosper into a big tree. A thought can change the decision of a person which changes the habit and eventually changes his character. Your thoughts are deeply connected with you and affect the outside world. People think their life depends on external factors such as the economy, politics, peers, boss, good or bad luck, etc., but it's not as simple as it looks. Rather, their thoughts equally influence the world as it does them. Therefore, it is difficult to define one's character by looking at his or her environment. For the same reason, you may find some good-hearted people in jail and some villains on the streets. Your thoughts are your affirmations. If you have a positive attitude it will improve your heart rate, sleep, and your skin so you will look younger. Whereas a negative thought will attract heart problems, insomnia, and other health-related problems, resulting in age faster.