What Jewish belief means behave properly even if others don't?

Answer 1

politeness

Answer:

The following quote from Pirkei Avot (ch.2):

ובמקום שאין אנשים, השתדל להיות איש

(Where there are no men, make an effort to be a man).

It is interpreted to mean that even where other people are acting in such a bestial way, so as not to be considered "proper men", the Jew should try to elevate himself beyond that and be a "proper man".

Answer 2

Yes, it most certainly does. In fact, one of the main focuses of the Tanach (Jewish Bible) is to provide Jews with the guidelines for living a good and righteous life. Judaism is about what's called 'tikkun olam' - repairing the world and making it better.

Additionally, Judaism is somewhat unique amongst religions as it teaches to do good simply for the sake of doing good. There are no punishment (hell/damnation)/reward (heaven) incentives in Judaism.

Answer 3

Yes.