Four perversions - Anguttara Nikaya 4.49
There are four perversions, four wrong-views resulting from improper use of mind. First, a person may confuse what is constant with what is inconstant. Second, a person may confuse what is pleasant with what is painful. Third, a person may confuse what is self with what is not self. Fourth, a person may confuse what is desirable with what is undesirable. These perversions result in insanity, and restlessness, loss of satisfaction and the ability to become satisfied, an inability to become free from distress.