In general, it is somewhat easier to pinpoint the meaning of ‘abnormality’ than ‘normality’. Ever since the time of the Ancient Greeks, the meaning of normality has undergone a variety of different interpretations. Contemporary approaches to the concept do not attempt to provide a monolithic definition, but rather articulate a number of interrelated meanings. One such attempt can be found in the book by Daniel Offer (1930-2013) and Melvin Sabshin (1926-2011)) entitled Normality theoretical and clinical concepts of mental health, 1984. They treat normality as consisting of four notions:
• normality as a Utopian ideal: what is valued as ideal and something that changes across historical time within cultures and societies. In essence, it determines the other notions of normality despite contentions to the contrary stemming from the belief that there can be a value-free science.
•normality as average: what is expectable relative to others based on normative age standards derived from standardised tests. This interpretation of normality seems to have originated with the statistician Adolphe Quetelet (1796-1874), with his notion of the ‘average man’ (i.e., the mean of the mean values of a range of traits) as expounded in his Treatise on man (1835). The problem, of course, with Quetelet’s approach still remains: where on a normal (Gaussian) distribution does one set the cut-off point to distinguish ‘abnormal’ from ‘normal’? Moreover, it has been estimated that only about 6/1000 people have mean values for all relevant traits, whether they be physical or psychological.
•normality as health: the absence of impairment, disability or handicap. This notion of normality appears to stem from the so-called German constitutional theorists at the beginning of the 20th century, and rests on the assumption that ‘abnormal’ individual lacks species-typical levels of functioning. Closely related to normality as average, there have been attempts to link the two in what has been termed ‘biostatistical theory‘ [e.g., see Boorse, C. (1977). Health as a theoretical concept. Philosophy of Science, 44, 542-573].
‚•normality as transaction: normality is a continuously changing relationship between individuals (e.g., parent and child), with each partner defining the other’s normality. Essentially, it amounts to being successful in interpersonal relationships such that one is able to conform to social expectations while at the same time being able to express one‚was individuality
A similar, diverse approach as to what constitutes normality can be found in Murphy, E.A. (1979 ). The epistemology of normality. Psychological Medicine, 9, 409-415. Here, perhaps with tongue in cheek, it is concluded that normality is more or less what a society can afford.
See Disability, Eugenics, Handicap, Impairment, Typological thinking