, Volume 40, Issue 3, pp 617–631 | Cite as

In Defence of Ockhamism



Ockhamism implies that future contingents may be true, their historical contingency notwithstanding. It is thus opposed to both the Peircean view according to which all future contingents are false, and Supervaluationist Indeterminism according to which all future contingents are neither true nor false. The paper seeks to defend Ockhamism against two charges: the charge that it cannot meet the requirement that truths be grounded in reality, and the charge that it proves incompatible with objective indeterminism about the future. In each case, the defence draws on the idea that certain truths are truths only courtesy of others and of what makes the latter true. After introduction of the Ockhamist view, its competitors and implications, a suitable definition of grounded truth is being devised that both is faithful to the spirit of the grounding-requirement and allows the Ockhamist to heed that requirement quite comfortably. Then two senses in which the future might be open are being introduced, indeterminacy as failure of predetermination by past and present facts, and indeterminacy as failure of entailment by past and present truths. It is argued that while openness in the former sense, but not in the latter sense, coheres with the Ockhamist view, it is only openness in the former sense that matters for objective indeterminism.


Time Open future Indeterminism Future contingents Grounding 



I am grateful to the following colleagues, students and friends for their critical comments that helped to improve the paper significantly: Fabrice Correia, Manuel García-Carpintero, Carl Hoefer, Dan López de Sa, Giovanni Merlo, Ivan Milic, Nathan Oaklander, Pablo Rychter, Albert Solé, Stephan Torre, and Richard Woodward. The research leading to these results has received funding from the European Community’s 7th Framework Programme under grant agreement PITN-GA-2009-238128, and was also partially funded by the Consolider-Ingenio project CSD2009-0056 and the project FFI-2008-06153, both financed by the Spanish Ministry of Science and Innovation (MICINN).


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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.ICREA and Department of Logic, History and Philosophy of ScienceUniversity of BarcelonaBarcelonaSpain

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