People who shy away from public gatherings, who by nature do not seek out the company of others, or who prefer their own company to that of others are often considered inferior to those who are more sociable.
The argument might even be made etymologically: the English word “idiot” is derived from the Greek word ἰδιώτης (idiōtēs). Liddell and Scott give this for the first entry of ἰδιώτης (idiōtēs): “a private person, one in a private station, an individual, opp. to stratēgos, a private soldier: also an individual, opp. to polis.” Therefore, so the argument goes, the “idiot” was the one who shied away from public life.
Furthermore, Aristotle argued that “Man, by nature, is a political animal.” “Political” in this sense means “the ordering and structuring of society—living in community.” The polis was the city, the community. Note that Liddell and Scott contrast idiōtēs with polis.
So, are introverts inferior? If only etymologies were arguments. Simply because the English word “idiot” derives from the Greek word that meant “a private person”—it does not follow that “a private person” is an “idiot.” So, I’ll continue to screen my calls and not answer the door simply because there is a ring or a knock.
Most people would balk at the idea that I’m an introvert. I don’t know myself. I think it really just depends on the day.