He once discussed NULL pointers. He made a well-reasoned argument about how a proper language should use some other method to properly distinguish between NULL and "I really do have a pointer here", such as ML's option types or Haskell's Maybe types or something. Basically the "million dollar mistake" argument.

He then went on to say something basically like, "Thus, there is no such thing as a NULL pointer. It is a myth. It simply doesn't exist." Which is patently false, and I find rather funny. Languages do have NULL pointers whether they should or not. I can assign a value of NULL to my pointer in C -- they exist. They are not a myth.

A friend of mine, who is a TA for our operating systems class, whispered to me, "Hm, NULL pointers don't exist?! I guess I'll go tell my students that."

Can you link to the context of that statement?

I think maybe he was trying to say something else, but said it in a misleading/funny way?

He said it in a lecture, but I'm pretty sure he was dead serious.