Tales of the Unexpected was a long-running DC scifi/horror series that specialized in stories about stuff nobody anticipated would happen. Its covers were also unexpectedly unexpected, and we can learn a lot about expectations just by looking at them. Unexpected.
When you're a brain in a tank, you've got a lot of time to think about stuff. And one of the things you ponder is: how many kinds of disembodied brains does science fiction have? The answer: six!