One more thing, then to bed go I: I'm rather surprised at the number of stories by Brown and Sturgeon from the '40s in which a male protagonist is about to propose to his girlfriend, but then something weird happens and he decides that he can't because he might be insane, and it would be horribly unfair of him to ask a girl (I use the term because they do) to marry him if he is insane.
Was this a common situation in the '40s? Or just a common fear?
Or maybe it was just a common trope. If all else fails, call it a genre convention.