How to Respond If Someone Calls You a Racist or Says "You Are Full of Shit"

How do you respond to someone who tells you "You are full of s--t" or to someone who calls you a racist, a sexist, a bigot, a hater, a fascist, a Nazi, a troll, a reactionary, a crank, or a clown?

Simple.

You thank them.

Profusely.

Very profusely.

Tell them:

I am touched by your words and I wish to thank you very much for calling me a racist/a hater/a sexist (and/or for saying that I am full of shit), in view of the fact that that shows that you have run out of arguments and that you now have no choice but to resort to ad hominems and insults.

If you wish to elaborate:

Of course, being liberals, people like you have no rational arguments to begin with, that is, none beyond your self-serving (and never-ceasing) statements of self-praise, such as that you are the most intelligent people that ever lived, that you are the most compassionate people who ever lived, that you are the most loving people who ever lived, that you are the most generous, most humanitarian, most peaceful, most tolerant people who ever lived, and that nobody before you has been as open as you are to debate and to discussion.

Related: Americans Anonymous