Is the Principle of Sufficient Reason Dispensable in a Cosmological Argument for an Ens Necessarium ? An Inquiry with Peirce

Abstract This essay examines the relationship between the principle of sufficient reason (PSR) and the claim of a necessarily existing being (NEB) within the context of cosmological arguments for the existence of God. While the contemporary philosopher of religion Friedrich Hermanni, following Leibniz, regards the PSR as implying – or even being equivalent to – the assumption of a NEB, Charles Sanders Peirce, who shares certain philosophical concerns with Leibniz but writes under the influence of 19th-century evolutionary theories, appears to treat the NEB either as having a projection function or merely as a conjunct. This article seeks to illuminate the distinct conceptual backgrounds – particularly regarding the theory of signs and the paradigms of logic – and to explain how Peirce, by taking into account vagueness and indeterminacy, arrives at a different understanding of inference, metaphysics, reality, and the idea of God as the Ens necessarium .