There are many reasons why we feel stressed and it varies from person to person. However, it is always you who is stressed. That's why it's important to change your thinking. It's obvious, but it may not be obvious to some. For example, let's say you fall and drop your phone while walking down the street and your phone gets scratched. The emotional pain varies depending on what you think at this time, for example, ah... I fell and got a scratch on my phone, I'm having bad luck today. It is divided into cases such as “I’m glad my phone didn’t break” and “I’m lucky today.” In the former case, there is a lot of mental pain due to pessimistic thoughts, but in the latter case, there is less mental pain because it is fortunate that a more serious accident did not occur. A certain amount of optimism is also necessary.