ITHACA—Democracy is inherently fraught. At its core lies the difficulty of translating individual preferences into a coherent social choice, a problem famously captured by Nobel laureate economist Kenneth Arrow’s impossibility theorem and later developed by another Nobel laureate, Amartya Sen, in his 1970 book Collective Choice and Social Welfare. Just as Euclid did for geometry long before them, Arrow and Sen gave political economy a rigorous axiomatic framework, in the process revealing the limits of collective decision-making.

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