, Volume 75, Issue 1, pp 45–60 | Cite as

Dream Skepticism and the Conditionality Problem

  • Kristoffer Ahlstrom
Original Article


Recently, Ernest Sosa (2007) has proposed two novel solutions to the problem of dream skepticism. In the present paper, I argue that Sosa’s first solution falls prey to what I will refer to as the conditionality problem, i.e., the problem of only establishing a conditional—in this case, “if x, then I am awake,” x being a placeholder for a condition incompatible with dreaming—in a context where it also needs to be established that we can know that the antecedent holds, and as such can infer the consequent, i.e., “I am awake.” Sosa’s second solution, in terms of so-called reflective knowledge, is shown to land him in the dilemma of either facing yet another conditionality problem, or violating an internalist constraint that he explicitly grants the skeptic with respect to what kind of factors can be legitimately invoked in our account of how we may know the relevant antecedent. For these reasons, I conclude that Sosa has not solved the problem of dream skepticism.


True Belief Imagination Model Perceptual Belief Animal Knowledge Internalist Constraint 
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The author would like to express his deep gratitude to Hilary Kornblith, Louise Antony, and two anonymous referees for this journal for valuable feedback on previous versions of this paper. Research underlying the present paper was conducted with generous support from the Fornander Foundation and the Hagendahl Commemoration Fund.


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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.Department of PhilosophyUniversity of CopenhagenCopenhagenDenmark

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