from Eccentrics: A Study of Sanity and Strangeness by Dr. James Weeks & Jamie James (Villard, 1995)

“Precisely what does it mean, in the first place, to call [someone] eccentric? The dictionary tells us that an eccentric is someone who deviated from the conventional or established norm, who is different from the rest of us – hardly a definition that is likely to satisfy a trained psychologist. That description applies to just as well to a criminal or a person with a birth defect.
“What does science have to say about the subject? Ten years ago, when I first began asking these questions, I undertook a thorough search for some answers through the vast, forbidding tundra known as the scientific literature. One would expect that abnormal or clinical psychology, which has produced definitive treatises on every conceivable deviation from normal behavior, must surely have established a sound, widely tested profile of the eccentric, one that carefully distinguishes the syndrome from the other, harmful forms of mental abberation. Yet in fact there is next to nothing to be found on the subject of eccentricity in modern scholarly literature. Because eccentrics tend to be healthier than most people, they rarely seek the services of the medical profession, and the medical profession, as a rule, is not very interested in those who do not seek it out…
“Thus it appeared to me that actual scientific knowledge about eccentrics was virtually non-existent. Nature abhors a vacuum, and so does a scientist: since no study of eccentrics existed, I decided to begin my own. It occurred to me that it would be a great advantage to psychology to have a basic understanding of the thought process of people who come to regard themselves, and who are regarded by others, as eccentrics, if only to help distinguish their behavior from certain forms of mental illness.”

“The study became a group portrait of people as varied as society at large, yet with many common traits. A profile emerged with fifteen characteristics that applied to most eccentrics, ranging from the onvious to the trivial. We found that an eccentric may be described in the following ways, more or less in descending order of frequency:

1. nonconforming
2. creative
3. strongly motivated by curiosity
4. idealistic: he wants to make the world a better place and the people in it happier
5. happily obsessed with one or more hobbyhorses (usually five or six)
6. aware from early childhood that he is different
7. intelligent
8. opinionated and outspoken, convinced that he is right and that the rest of the world is out of step
9. noncompetitive, not in need of reassuring or reinforcement from society
10. unusual in his eating habits and living arrangements
11. not particularly interesting in the opinions or company of other people, except in order to persuade them to his – the correct – point of view.
12. possessed of a mischievous sense of humor
13. single
14. usually the eldest or an only child, and
15. a bad speller”