Is Putnam’s Internal Realism Solipsistic?

Abstract

In this essay I claim that Hilary Putnam’s recent rejection of his former doctrine of internal realism as solipsistic is a misfired claim. Putnam’s rejection of his early doctrine is illustrated by the criticism of his own verificationist account of truth and justification, which is based on the counterfactual conditional: “S is true if and only if believing S is justified if epistemic conditions are good enough”. By accepting that whatever makes it rational to believe that S also makes it rational to believe that S would be justified were conditions good enough, Putnam concludes that the verificationist unavoidably steers between solipsism and metaphysical realism. As opposed to this, I claim that Putnam’s later criticism of his own internal realism fails to acknowledge the pragmatic side of this philosophical approach; namely, the idea that, regardless the close relation between truth and justification, not all sentences in a language game are to be understood in a verificationist fashion. Thus, the understanding of the counterfactual “S would be justified if epistemic conditions were good enough” doesn’t call for a verificationist reading, which, as Putnam claims, yields solipsism, but rather, for a pragmatic approach which emphasizes on the non-formality of language understanding.