# Moore’s Paradox as an Argument Against Anti-realism

## Abstract

Moorean validities are any in-general invalid inferences such as: “*P*; therefore I believe that *P*”. While these are prima facie invalid, they have no counterexamples, since any assertion of the truth of the premise pragmatically forces the conclusion to be true. I first show that Dummettian anti-realists have a seemingly impossible time explaining why Moorean validities are not valid. Then I argue that the anti-realist could restrict applications of Moorean validities to inferential situations outside of the scope of things assumed hypothetically for further discharge. In conclusion, I show how Brogaard and Salerno’s argument against Neil Tennant runs afoul of this restriction and also suggest that famous arguments by Berkeley and Davidson do as well.

## Keywords

Realist Conception Natural Deduction System Correct Belief Proof Theoretic Semantic Double Negation Elimination## Notes

### Acknowledgments

I would like to thank Berit Brogaard, Emily Beck Cogburn, Jacques Dubucs, Jeff Roland, Joe Salerno, Mark Silcox, and Neil Tennant for conversation and inspiration. This paper arose out of sustained reflection on [2, 8]. I would have liked to further discuss the parts of Brogaard and Salerno’s piece that strike me as both non-trivial and true (i.e. the important restrictions on various options for an anti-realist account of modality), as well as to have explored a Dubucsian reaction to Moorean validities in more detail. However, space-time constraints, combined with the internal logic of the paper, prohibited this.

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