"Words have power. They have the power to teach, the power to wound, the power to shape the way people think, feel, and act toward others. When a stigmatized group of people, such as those with mental illnesses, is struggling for increased understanding and acceptance, attention to the language used in talking and writing about them is particularly important." 1
Words can limit potential. People with mental illnesses want to be known for their skills, talents, and abilities, not for their diagnosis or "label." A mental illness, like a physical illness, does not define a person. In addition, terms such as "crazy" or "nuts" reinforce the discrimination and negative attitudes associated with mental illnesses and often keep those who need and want help from seeking treatment.
Focusing on use of language is often the first place to start addressing social exclusion and discrimination against people with mental illnesses.
Information on this topic can be found in the following materials.
1Wahl, O. F. (June 1998). People first language matters. The Bell (newsletter of the National Mental Health Association).