Figures of speech of the patient is mentally unstable

It is frequently asserted by those associated with anti-psychiatry that "mental illness" is nothing more than a metaphor, a figure of speech, used to describe socially deviant persons

Explanation:

no biological tests for mental illness, it is alleged that mental illness is a merely a myth whose only purpose is to justify psychiatric coercion. First espoused by the psychiatrist Thomas Szasz in his classic 1961 book The Myth of Mental Illness and 1960 paper of the same title, this is an argument I am well familiar with and supported for quite a few years.