Napoleon complex is a pejorative term describing a disproven psychological condition which is said to exist in people, both men and women, of short stature. It is also known as 'Napoleonic Complex'.  It is characterized by overly-aggressive or domineering social behavior, and carries the implication that such behaviour is compensatory for the subject's stature. The term is also used more generally to describe people who are driven by a perceived handicap to overcompensate in other aspects of their lives. Other names for the term include Napoleon syndrome and Short Man syndrome.
The Napoleon complex is named after Emperor Napoleon I of France. The conventional wisdom is that Napoleon compensated for his lack of height by seeking power, war, and conquest. Though he was long reported to have stood at only 5 ft 2 in (1.57 m), historians have now suggested Napoleon was actually 5 ft 6 in (1.68 m) tall. Napoleon was often seen with his Imperial Guard, which contributed to the perception of his being short because the Imperial Guards were above average height.
In 2007, research by the University of Central Lancashire suggested that the Napoleon complex (described in terms of the theory that shorter men are more aggressive to dominate those who are taller than they are) is likely to be a myth. The study discovered that short men were less likely to lose their temper than men of average height. The experiment involved subjects dueling each other with sticks, with one subject deliberately rapping the other's knuckles. Heart monitors revealed that the taller men were more likely to lose their tempers and hit back. University of Central Lancashire lecturer Mike Eslea commented that "when people see a short man being aggressive, they are likely to think it is due to his size, simply because that attribute is obvious and grabs their attention."
The Wessex Growth Study is a community-based longitudinal study conducted in the UK that monitored the psychological development of children from school entry to adulthood. The study was controlled for potential effects of gender and socioeconomic status, and found that "no significant differences in personality functioning or aspects of daily living were found which could be attributable to height"; this functioning included generalizations associated with the Napoleon complex, such as risk-taking behaviours.
Abraham Buunk, a professor at the University of Groningen in the Netherlands, has found evidence of the small man syndrome. Researchers at the University found that men who were 1.63 m (5 ft 4 in) were 50% more likely to show signs of jealousy than men who were 1.98 m (6 ft 6 in).
In evolutionary theory
The term "Napoleon complex" has been used in scientific research on the phenomenon of smaller organisms acting aggressively towards larger organisms. In contrast to the many examples of larger organisms acting aggressively towards smaller organisms in the animal kingdom, some studies of aggressive behaviour in organisms have detected cases where smaller individuals initiate aggression. A 1995 study of contests between males in the swordtail fish species Xiphophorus nigrensis and Xiphophorus multilineatus found that 78% of observed fights were initiated by the smaller fish, and in 70% of fights the fish that delivered the first bite lost the conflict. From an evolutionary perspective, this "Napoleon complex" behaviour seems irrational.
Posited explanations include an asymmetry in the value of the contested resource to the two combatants (the individual with lower resource holding potential may attack first if the value of the resource is greater for him), a misconception on the part of the weaker organism about his own strength, and the "Desperado Effect", where omega males attack because they have no other opportunities to gain resources.
Ohio University researchers have suggested another explanation, that the stronger contestant benefits from delaying escalating a display to a fight, "leaving the initiative to the opponent and hoping for him to retreat, either because of realistic perception of his chances to win the fight or by mistake. ... our proposed explanation for what is commonly considered the 'Napoleon Complex' might be appropriately identified as the 'Gentle Giant Syndrome.'"
In game theory
A University of Leeds study concluded that in game theory, a Napoleon complex is an evolutionarily stable strategy, where smaller individuals are more aggressive than larger opponents, is possible when smaller individuals display and larger individuals retreat; this may occur when the smaller individual has some chance to win a fight and resources are abundant and of relatively low value, or when the value of the resource is too small to the larger individual when compared to the injury risk.
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