Ian O'Doherty: Comedian or cynic? Why I've fallen out of love with Sarah Silverman . . .
A good comedian knows exactly where the line is. And then crosses it. When you come across a performer who is prepared to do a metaphorical long jump across that line and, crucially, still be funny, then you know you have found one to cherish.
That's why I love Joan Rivers with a passion that is rather inappropriate when you consider she's in her 70s.
But, by God, does she hunt down sacred cows and slay them with abandon.