Centuries of economic hypotheses have been based on the premise of rational actors: when given a choice between two items, people select the one they value more. But as with many simple premises, this one has a flaw in that it is demonstrably untrue.
Yet that was never really the case. Too many exceptions mean a rule was never a rule anyway - there are lots of examples where people act against their own apparent interests. One of these biases — the mere fact of possessing something raises its value to its owner — is known as the "endowment effect."
A new paper seeks to address whether this bias is truly universal and speculates that it may have been present in humanity's evolutionary past.