From Neil Gaiman’s Conversation with Michael Chabon:
In the years that followed, we would have the kind of conversations where Terry would say to me things like, “So I’m done with the Discworld and now I’m going to do this big science fiction series, I’ve come up with it, and this is the plot of the science fiction series.”, and would tell me all about it and get to the end, and I’d say, “Well, that’s all very well, but you should do a book about Death.” And then a week later my phone would ring and I’d pick it up, and a voice would say, “You bastard, it’s called Mort.” and he’d put the phone down.