Are thoughts useful or harmful?

Hundreds of thoughts visit us during the day. And we never muse where they are from. So let’s catch one more thought and talk about its nature. What are thoughts? It is an action of mind. Thought is a thing that makes us human and defines from the animals. René Descartes considered thinking as a determination of existence. The process of thinking itself is neutral. It is like a knife – cannot be good or bad, it depends on the use. (For it can be used at home, and at the same time it can be used for damage.)