Arthur D. Hlavaty

I suppose it depends on how you look at it. Sure, cold fusion would either work or it wouldn't. But the more you look at chaotic systems where you can't control the variables or the starting conditions, the more likely you are to find more complicated results. So the effects of drugs or of eating or not eating certain foods will be far more difficult to tease out. It's not necessarily psychology per se.

The perfect results will be replicable anywhere - but, for example, I've tasted some Japanese "snacks" that were so odd to me that even if they took will for most Japanese folks to resist, they'd be easy for me to resist. Similarly, if you just randomly set up shop where a wave of Atkins/Paleo dieting took hold, resisting cookies might be easier or much harder. Or, hell, if you didn't close the cookies tightly enough so they got cardboard-like and now *everyone* can resist them, but you might see a scientifically significant uptick in cookie sales.

I don't want to explicitly bless the notion of willpower depletion; "difficult to replicate" doesn't mean "still probably true". But it does make sense to me, and I'd like to think it exists on some level, even if it's too small to be generally worth measuring.