I realize this question is contrived, but I figure it might provoke some fun discussion, so here goes:
If you could push a button and have your brain modified to precisely remove a cognitive bias (and have no other unnecessary effects—most convenient possible world), which would you choose? Why?
What if you were choosing for the whole human race?
So, because the circumstances of your upbringing made you much safer from AIDS, you think blaming those with AIDS for their own problems is justified? And this is your example of why the just world fallacy might actually be a useful and accurate heuristic?
"Blame" is a moral word, and hence contentious. Let's instead use words like "causation", "knowledge," and "foreseeability."
Consider someone who got AIDS via needle-sharing. Clearly, they took actions (sharing a needle) that caused the harm in a "but-for" sense. They knew (or can be deemed to have known ) that sharing needles risks spreading blood-borne pathogens, of which AIDS is one. The harm was clearly foreseeable. So it's quite correct to say that they caused themself to get AIDS. Indeed, if the addict... (read more)