This is an interesting philosophy. After hearing this, I searched the web and came up on a youtube video of a cutscene in the game Assassins Creed. I've never played this game, but it does look interesting.

http://www.youtube.com/watch?v=y_sEyky7NlY

I like the idea behind this.

Nothing is true = Nothing is in solid black and white, right and wrong standards. standards are set by society. and we have the illusion that we must follow these standards. we can either conform or transcend to them.

Everything is permitted = along with nothing being black and white, everything is permitted in certain circumstances. Murder is wrong but killing in self defense is understandable.