Time Travel and the Limits of Logic: Why the Grandfather Paradox Continues to Resist Solution

Strany: 196 - 217

Jazyk: eng

David Lewis’s influential solution to the grandfather paradox treats time traveler Tim’s failure to kill his infant grandfather as an ordinary case of unsuccessful action. Relative to the facts at the time of the attempt, Tim can succeed, and his failure is no more mysterious than missing a basketball shot. I argue that Lewis’s solution is mistaken, and that a more recent alternative—the “strategy by analogy with the impossible,” which likens Tim’s failure to other failures to achieve logically or mathematically impossible tasks (e.g., crossing each of Königsberg’s seven bridges exactly once)—also fails. Drawing a distinction between self-explicable and self-enforcing failures on the one hand, and Tim’s failure on the other, it is shown that Tim’s failure differs from ordinary failures to achieve the impossible insofar as the latter require no causal intervention: the impossibility itself fully explains and brings about the failure. Tim’s case is structurally different. While it is impossible for his grandfather to both survive and not survive, nothing in the impossibility itself explains why his grandfather must survive rather than die—a selection between two contingent-seeming alternatives that ordinarily falls outside logic's purview and within causation’s. The grandfather paradox therefore occupies an unrecognized middle ground: a necessary failure (relative to any facts) that nonetheless seems to demand causal enforcement, leaving the puzzle’s deepest difficulty unresolved by either of the two leading strategies.

ISO 690:

Loewenstein, Y. 2026. Time Travel and the Limits of Logic: Why the Grandfather Paradox Continues to Resist Solution. In Organon F, vol. 33, no.2, pp. 196-217. 2585-7150. DOI: https://doi.org/10.31577/orgf.2026.33205

APA:

Loewenstein, Y. (2026). Time Travel and the Limits of Logic: Why the Grandfather Paradox Continues to Resist Solution. Organon F, 33(2), 196-217. 2585-7150. DOI: https://doi.org/10.31577/orgf.2026.33205

Vydavateľ: Filozofický ústav SAV, v.v.i, Filosofický ústav AVČR

the Creative Commons Attribution-NonCommercial 4.0 International Public License (CC BY-NC 4.0)