"Everyone says ..." - how to deal with emotional argument like this.

When you confront someone about something they did (assuming something bad), and when they blasted back saying something obscure like:
-Well people have been saying about you ...
-Everyone says you ...
-The administrators say you ..
-The teachers say you ...

etc., how would you respond? The above are of course obscure since we don't know who these "mentioned people" are and the person who's mentioning this could be lying or just trying to provoke you.

Put the internet to work for you.

via Personal Recipe 2629979