[The following book excerpt is about introverts and extroverts. I posted it here because many chess players are introverts and often perceived as social perverts, undeservedly.]

In the early 1900s, psychoanalyst Carl Jung was working with Sigmund Freud and Alfred Adler, two other pioneering psychoanalytic theorists, when he noticed something puzzling. When Freud and Adler discussed the same case histories of patients, they focused on very different information. They also had developed almost opposite theories. Jung thought they had both captured something valuable. Jung gave it some thought (guess which Jung was, an introvert or an extrovert?) and developed his own theory.

Jung thought Freud was extroverted because his personal orientation was outward toward the world of people, places, and things. Many of Freud's theories were developed in conjunction with extensive correspondence and discussions with numerous colleagues. Freud believed that the goal of psychological development was to find gratification in the world of external reality. Jung thought Adler was introverted, since his theory and focus were inward toward one's own thoughts and feelings. Adler's theories were based on the internal struggle to overcome the feelings of helplessness expressed in his term "inferiority complex." He saw people as creative artists shaping their own lives.

Freud's theoretical differences with Adler and Jung ended in bitterness. The three parted company and each went his own way. At that point, Freud began to use the concept of introversion as a negative, implying a turning inward away from the world, in his writings about narcissism. This shifted the evolution of the concept of introversion away from healthy and toward the unhealthy, a misconception that remains to this day.

Jung continued to develop his theory, and he surmised that we are born with a temperament endowment that locates us somewhere on a continuum between very introverted and very extroverted. He believed that there was a physiological foundation for these dispositions. Science is now finding his intuition was right! He realized we could adapt best in the world if we could move easily on the continuum, introverting and extroverting when needed. However, he recognized that humans don't seem to work that way: We are oriented or pulled in one direction more than the other. He concluded that we all have a "natural niche" where we function best. Jung also thought that, apart from either extreme, any place on the continuum is healthy. Jung believed that it is harmful to push a child outside of the natural range of his or her temperament, thinking this would "violate the individual's innate disposition." In fact, he thought this was the cause of some mental illness.

However, he pointed out that the other aspects of the continuum are still available to us. Our ability to move on the continuum can improve with our awareness of the process. For example, you can learn to store up energy, and thereby have a reserve to enable you to use your less natural side. Think about writing all day with your less dominant hand. You could do it, but you would use more exertion and concentration to focus. Jung thought this was what it is like to function outside your natural niche. You can do it, but it will consume extra energy without creating any new energy.

...The current explosion in gene and brain mapping is creating a scientific window into the mysteries of human nature. Some of Charles Darwin's theories are being combined with those of psychology to form a new perspective called evolutionary psychology. Researchers in this field wonder if certain behavioral strategies increase out chances for survival and reproduction. Darwin studied the finches on the Galapagos Islands. He found that in response to environmental demands, the birds had adapted and developed specialized beaks. The diversity of beaks allowed them access to different feeding niches. Instead of eating only insects, they could now eat a varied diet consisting of insects, berries, seeds, and nuts.This increased the entire species' chances for survival.

When Jung, an admirer of Darwin, first wrote about introversion and extroversion, it was clear that he was thinking about temperament from an evolutionary perspective. He saw each variation of temperament as requiring its own optimal environment, a natural niche it could flower. Having people who thrive in different optimal environments increases the chances of survival of the human race as a whole. It is nature's way to preserve her species.

Introverts, Jung wrote, conserve their energy, have fewer children,
have more ways of protecting themselves, and live longer. Because they appreciate a simpler life, make intimate attachments, and plan and reflect on new ways of doing things, they encourage others to be prudent, develop self-reflection, and think before acting.

Jung thought extroverts, on the other hand, expend their energy, propagate more often, have fewer ways of protecting themselves, and die off faster. Extroverts act quickly when danger threatens and have the ability to get along with large groups. Because they have a quest for venturing farther afield to locate new land, food, and other cultures, they encourage far-ranging exploration.

Source: Laney, M. O. (2002). The Introvert Advantage (pp. 26-28, 62-63). New York: Workman Publishing.

That was a great and interesting excerpt you got there, Ganglion. I would agree with the thesis that shifting between the intro-extro continuum is healthy. I kind of act that way myself.

From my point of view, though, introverts aren't bad, as long as they don't go emo and cut themselves in the wrist or something like that. In fact I think extroverts are worse because sometimes they tend of to overact and have loose tongues. Such people can be hazardous. A classmate of mine comes to mind...

Anyway, thanks for the excerpt ^^. I like stuff regarding psychology and the mind D: