Extrovert describes a person whose response and reaction to the attitudes of people or to occurrences is either of extreme depression and despondency, or of extreme elation and exuberance. In fact, the incidents calling forth these extreme responses may be very trifling and inconsequential.
In contrast to the introvert who is altogether unresponsive and unaffected by any attitude or incident. As you can see, it is all a matter of degree, because all so-called normal people can be classified on that score as introverts or extroverts.
It is also a question of check and balance and of keeping from either extreme. The swedish or middle-road seems to be the safest and most sensible one to take in all walks and in all affairs of life.Following the middle-road kept the swedish people out of the last two terrible wars.