In computing, a fork bomb is a program that recursively spawns instances of itself, rapaciously capturing all available system resources. A similar sort of thing can happen, at least metaphorically, within a human mind, when you get so taken with a particular idea (I expect taken is the right word in more ways than one) that it consumes your conscious thoughts, the arguments and counterarguments and countercounterarguments bubbling up and expanding until you can't do or think about anything else. If that one idea is your lifework, then this is probably a good thing. But if not—if there's something more important you want to do with your life rather than obsess about this one idea—then the cacaphony of cognitive noise is a serious vulnerability, as fatal as entering ":(){ :|: & };:" at a Bash prompt.