Peirce, Charles Sanders (1839–1914)
Authors: Hookway Christopher 
Published: September 2018

Peirce was an American philosopher, probably best known as the founder of pragmatism and for his influence upon later pragmatists such as William James and John Dewey. Personal and professional difficulties interfered with his attempts to publish a statement of his overall philosophical position, but, as the texts have become more accessible, it has become clear that he was a much more wide-ranging and important thinker than his popular reputation suggests.
He claimed that his pragmatism was the philosophical outlook of an experimentalist, of someone with experience of laboratory work. His account of science was vigorously anti-Cartesian: Descartes was criticized for requiring an unreal ‘pretend’ doubt, and for adopting an individualist approach to knowledge which was at odds with scientific practice. ‘Inquiry’ is a cooperative activity, whereby fallible investigators progress towards the truth, replacing real doubts by settled beliefs which may subsequently be revised. In ‘The Fixation of Belief’ (1877), he compared different methods for carrying out inquiries, arguing that only the ‘method of science’ can be self-consciously adopted. This method makes the ‘realist’ assumption that there are real objects, existing independently of us, whose nature will be discovered if we investigate them for long enough and well enough.
Peirce’s ‘pragmatist principle’ was a rule for clarifying concepts and hypotheses that guide scientific investigations. In the spirit of laboratory practice, we can completely clarify the content of a hypothesis by listing the experiential consequences we would expect our actions to have if it were true: if an object is fragile, and we were to drop it, we would probably see it break. If this is correct, propositions of a priori metaphysics are meaningless. Peirce applied his principle to explain truth in terms of the eventual agreement of responsible inquirers: a proposition is true if it would be accepted eventually by anyone who inquired into it. His detailed investigations of inductive reasoning and statistical inference attempted to explain how this convergence of opinion was achieved.
Taken together with his important contributions to formal logic and the foundations of mathematics, this verificationism encouraged early readers to interpret Peirce’s work as an anticipation of twentieth-century logical positivism. The interpretation is supported by the fact that he tried to ground his logic in a systematic account of meaning and reference. Much of his most original work concerned semiotic, the general theory of signs, which provided a novel framework for understanding of language, thought and all other kinds of representation. Peirce hoped to show that his views about science, truth and pragmatism were all consequences of his semiotic. Doubts about the positivistic reading emerge, however, when we note his insistence that pragmatism could be plausible only to someone who accepted a distinctive form of metaphysical realism. And his later attempts to defend his views of science and meaning bring to the surface views which would be unacceptable to an anti-metaphysical empiricist.
From the beginning, Peirce was a systematic philosopher whose work on logic was an attempt to correct and develop Kant’s philosophical vision. When his views were set out in systematic order, positions came to the surface which, he held, were required by his work on logic. These include the theory of categories which had long provided the foundations for his work on signs: all elements of reality, thought and experience can be classified into simple monadic phenomena, dyadic relations and triadic relations. Peirce called these Firstness, Secondness and Thirdness. He also spoke of them as quality, reaction and mediation, and he insisted that the error of various forms of empiricism and nominalism was the denial that mediation (or Thirdness) was an irreducible element of our experience. Peirce’s ‘synechism’ insisted on the importance for philosophy and science of hypotheses involving continuity, which he identified as ‘ultimate mediation’. This emphasis upon continuities in thought and nature was supposed to ground his realism. Furthermore, his epistemological work came to focus increasingly upon the requirements for rational self-control, for our ability to control our inquiries in accordance with norms whose validity we can acknowledge. This required a theory of norms which would explain our attachment to the search for truth and fill out the details of that concept. After 1900, Peirce began to develop such an account, claiming that logic must be grounded in ethics and aesthetics.
Although pragmatism eliminated a priori speculation about the nature of reality, it need not rule out metaphysics that uses the scientific method. From the 1880s, Peirce looked for a system of scientific metaphysics that would fill important gaps in his defence of the method of science. This led to the development of an evolutionary cosmology, an account of how the world of existent objects and scientific laws evolved out of a chaos of possibilities through an evolutionary process. His ‘tychism’ insisted that chance was an ineliminable component of reality, but he argued that the universe was becoming more governed by laws or habits through time. Rejecting both physicalism and dualism, he defended what he called a form of ‘Objective Idealism’: matter was said to be a form of ‘effete mind’.