"Mind over matter" is a phrase used to imply that the mind has the power to control the body and the physical world in general. It works on the premise that mental thoughts are stronger than physical properties.
The concept of mind over matter is typically applied in situations where mental powers are needed to solve problems or overcome difficult situations. It is also applied in situations where a person has a need to overcome physical pain. The Mayo Clinic promotes the power of positive thinking as an aid to healing the body. Religious and "self-help" personalities apply the basic principles of mind over matter to advocate positive thinking or to create a desired reality by imagining it to already be true.