An interesting example of the constraints placed on inquiry by stories that make some things difficult to conceive came up in Neurobiology and Behavior last week, during a discussion of the ability of the nervous system to generate outputs by itself rather than simply in response to external stimuli.
"Perhaps I've just had the idea that 'cause equals effect' engrained in my mind for so long that it's just difficult to sway me, but I still feel that there must be some input to trigger reactions in our body"