Non-epistemic Uncertainty and the Problem of Legal Line-Drawing

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Book Chapter

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This chapter seeks to identify one of the root causes of non-epistemic uncertainty. Many moral structures are inherently discontinuous, and some of the reasons for that will be laid bare. At the same time, the particular way in which these moral structures map onto the real world is loose and not strictly determinate. This results in bright-line rules whose discontinuous character is morally required but the location of whose continuities are not required to be in any particular place. To make this more concrete, consider Tversky and Kahneman’s famous prospect theory. The discontinuous treatment of gains and losses is arguably morally required, but the location of the inflection point is notoriously indeterminate. This produces a discontinuity that cannot be eliminated by making relevant legal and moral categories more scalar—resulting in non-epistemic uncertainty.


binary, decision making, law, prospect theory, repugnant conclusion, uncertainty, vagueness

Publication Title

Vagueness and the Law: Philosophical and Legal Perspectives