IN ORDER to diagnose any disease, a standard of reference is required. This standard is the state of health or normality. The term "health" is said to be the "general condition of the body or mind with reference to soundness or vigor, and to freedom from disease or ailment" (Random House Dictionary of the English Language, unabridged edition, 1966). When we say that a person is in good health, we mean that this person may indulge in physical and mental activities without distress, and is free from diseases that may threaten his or her well-being or life.1 Similarly, the orthodox medical definition of normal "denotes the absence of infection, disease, or malformation, or the absence of experimental, or therapeutic manipulations" (Webster's New International Dictionary of the English Language, second edition, unabridged, 1960).
With these definitions, we may expand the concept of normality to include and describe each of the