It is to believe the mind to be non-functionally pure[1] in the programmatic sense. Output based somehow other than purely on input.
And if that's the case, the question is where does that irrationality come from? A random number generator? Any developer knows there's no such thing as actual random. It's all either list based or based environmental aspects.
I don't see room for an argument to be made that the human mind isn't just mixing ideas/the environment that doesn't rely on some form of magical thinking.