Verificationism

Verificationism, also known as the verification principle or the verifiability criterion of meaning, is the philosophical doctrine which asserts that a statement is meaningful only if it is either empirically verifiable (i.e. confirmed through the senses) or a truth of logic (e.g., tautologies). Verificationism rejects statements of metaphysics, theology, ethics, and aesthetics, as cognitively meaningless. Such statements may be meaningful in influencing emotions or behavior, but not in terms of conveying truth value, information, or factual content. Verificationism was a central theme of logical positivism, a movement in analytic philosophy that emerged in the 1920s by philosophers who sought to unify philosophy and science under a common naturalistic theory of knowledge. Although earlier philosophical principles which aim to ground scientific theory in some verifiable experience are found within the work of American pragmatist C.S. Peirce and that of French conventionalist Pierre Duhem, who fostered instrumentalism, the project of verificationism was launched by the logical positivists who, emerging from the Berlin Circle and the Vienna Circle in the 1920s, sought an epistemology whereby philosophical discourse would be, in their perception, as authoritative and meaningful as an empirical science. Logical positivists garnered the verifiability criterion of cognitive meaningfulness from Ludwig Wittgenstein's philosophy of language posed in his 1921 book Tractatus, and, led by Bertrand Russell, sought to reformulate the analytic–synthetic distinction in a way that would reduce mathematics and logic to semantical conventions. This would be pivotal to verificationism, in that logic and mathematics would otherwise be classified as synthetic a priori knowledge and defined as "meaningless" under verificationism. Seeking grounding in such empiricism as of David Hume, Auguste Comte, and Ernst Mach—along with the positivism of the latter two—they borrowed some perspectives from Immanuel Kant, and found the exemplar of science to be Albert Einstein's general theory of relativity.