'The normal' as a culture-related concept: historical considerations

Three definitions of 'normal' are recognized: the normative or ideal, the average or statistical, and the medical or freedom from illness. We still retain from our historical past the notion that mental or emotional illness bespeaks, if not possession by spirits, at least an irreversible condition. A person who has once sought medical treatment for mental sickness is forever after viewed as suspect, as one who may relapse at any time. The modern norm of reason, as against unreason, reinforces distaste for mental illness. The withdrawal of the Eagleton candidacy in 1972 attests that our society is not yet ready to accept mental illness as treatable and curable. To aspire to the presidency or other high office is probably not 'normal' in the sense of not being 'average', and it is entirely possible that the norm of adaptive behavior is incongruent with ambition and exceptional ability. Should the eligibility requirement for leadership then be 'normal' in the sense of free from illness? Abraham Lincoln was subject to periods of acute depression, Winston Churchill was to a degree manic-depressive, and Woodrow Wilson suffered a series of 'nervous breakdowns' before serving as President. History has vindicated the mental ability and leadership qualities of these men. By modern psychiatric criteria for mental health, many creative scientists and artists would be considered abnormal. On the other hand, the concept of normalcy has recently been used to rationalize political misbehavior. Is it possible, then, to develop a viewpoint of 'normal' that is consistent with our culture, and yet at the same time is broad enough to encompass the uncommon?