The Trolley Problem is a staple of ethics courses and has even made its way into prime-time television. It’s a “problem” because it forces people to decide between two options that are both considered highly ethical: not choosing to kill someone and minimizing the total number of deaths. 

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Since testosterone influences both emotions and decision-making, many people had ideas about how it might alter the decisions made by people weighing these moral issues. But when a team of researchers from the University of Texas, Austin, decided to test those ideas, it turned out none of them was right.

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“The results of the current study yielded no evidence in support of any of the four preregistered hypotheses,” write the authors. Those given testosterone were no more likely to prefer taking action than those given the placebo. It was predicted that they’d also be more prone to make utilitarian judgements that minimize total casualties; this wasn’t true, either.”

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[I]t’s fair to say that we don’t know if testosterone is involved in this sort of decision-making, much less what its impact is if it is. 

Read full, original post: When it comes to moral decisions, testosterone doesn’t seem to do much