At first glance it looks like a paradox
, but it isn't.
"This is my favourite truth" can be a lie or a truth. It is a contingency. If it's true, it's true, if it's false, it's false.
"This is my favourite lie" is a falsehood. It is not a paradox. It is most certainly not true. No matter how you look at it, the sentence can only be false. (Of course I am talking about the sentence in its self-referential form; any other form is irrelevant to the argument).
The problem is, I like that sentence so much, that it has become my favourite lie. But it can't be. I want it to be. I want it terribly to be my favourite lie. But it won't. It can never be.
It is the one thing I know I can never have.