Very interesting, but according to this well-referenced paragraph on Wikipedia, the use of that word was a bit more complex:
> It is certainly true that the Greeks valued civic participation and criticized non-participation. Thucydides quotes Pericles' Funeral Oration as saying: "[we] regard... him who takes no part in these [public] duties not as unambitious but as useless" ... However, neither he nor any other ancient author uses the word "idiot" to describe non-participants, or in a derogatory sense; its most common use was simply a private citizen or amateur as opposed to a government official, professional, or expert. The derogatory sense came centuries later, and was unrelated to the political meaning.
> It is certainly true that the Greeks valued civic participation and criticized non-participation. Thucydides quotes Pericles' Funeral Oration as saying: "[we] regard... him who takes no part in these [public] duties not as unambitious but as useless" ... However, neither he nor any other ancient author uses the word "idiot" to describe non-participants, or in a derogatory sense; its most common use was simply a private citizen or amateur as opposed to a government official, professional, or expert. The derogatory sense came centuries later, and was unrelated to the political meaning.
https://en.wikipedia.org/wiki/Idiot