Jung on introversion:
"Everyone whose attitude is introverted thinks, feels, and acts in a way that clearly demonstrates that the subject is the prime motivating factor and that the object is of secondary importance."
"Always he has to prove that everything he does rests on his own decisions and convictions, and never because he is influenced by anyone, or desires to please or conciliate some person or opinion."
"In a large gathering he feels lonely and lost. The more crowded it is, the greater becomes his resistance. He is not in the least "with it," and has no love of enthusiastic get-togethers. He is not a good mixer. What he does, he does in his own way, barricading himself against influences from outside. . . . Under normal conditions he is pessimistic and worried, because the world and human beings are not in the least good but crush him. . . .His own world is a safe harbour, a carefully tended and walled-in garden, closed to the public and hidden from prying eyes. His own company is the best."
And extraversion:
"Extraversion is characterized by interest in the external object, responsiveness, and a ready acceptance of external happenings, a desire to influence and be influenced by events, a need to join in and get "with it," the capacity to endure bustle and noise of every kind, and actually find them enjoyable, constant attention to the surrounding world, the cultivation of friends and acquaintances, none too carefully selected, and finally by the great importance attached to the figure one cuts."
"The extravert's philosophy of life and his ethics are as a rule of a highly collective nature with a strong streak of altruism, and his conscience is in large measure dependent on public opinion."
"He has no secrets he has not long since shared with others. Should something unmentionable nevertheless befall him, he prefers to forget it. Anything that might tarnish the parade of optimism and positivism is avoided. Whatever he thinks, intends, and does is displayed with conviction and warmth."
The wording should be taken figurative as he tries to sum the terms up. As an example: Not all extraverts are dependent on public oppinion, but compared to the introverts they to great extends are. Also look at the words "in large measure", that mean some are more influenced by it than others.