Editing Otto Neurath (section)

===Philosophy of science and language===
Neurath's work on [[protocol statement]]s tried to reconcile an [[Empiricism|empiricist]] concern for the grounding of knowledge in experience with the essential publicity of science. Neurath suggested that reports of experience should be understood to have a [[Grammatical person|third-person]] and hence public and impersonal character, rather than as being first person subjective pronouncements.<ref name=SEP/> [[Bertrand Russell]] took issue with Neurath's account of protocol statements in his book ''An Inquiry Into Meaning and Truth'' (p.&nbsp;139ff), on the grounds that it severed the connection to experience that is essential to an empiricist account of truth, facts and knowledge.

One of Neurath's later works, ''Physicalism'', completely transformed the nature of the logical positivist discussion of the program of unifying the sciences. Neurath delineates and explains his points of agreement with the general principles of the positivist program and its conceptual bases:
* the construction of a universal system which would comprehend all of the knowledge furnished by the various sciences, and
* the absolute rejection of [[metaphysics]], in the sense of any propositions not translatable into verifiable scientific sentences.
He then rejects the positivist treatment of language in general and, in particular, some of [[Wittgenstein]]'s early fundamental ideas.

First, Neurath rejects the isomorphism between language and reality as useless metaphysical speculation, which would call for explaining how words and sentences could represent things in the external world. Instead, Neurath proposed that language and reality coincide—that reality consists simply of the totality of previously verified sentences in the language, and the "truth" of a sentence is about its relationship to the totality of already verified sentences. If a sentence fails to "concord" (or cohere) with the totality of already verified sentences, then either it should be considered false, or some of that totality's propositions must be modified somehow. He thus views truth as internal [[coherence theory of truth|coherence]] of linguistic assertions, rather than anything to do with facts or other entities in the world. Moreover, the criterion of verification is to be applied to the system as a whole (see [[semantic holism]]) and not to single sentences. Such ideas profoundly shaped the ''holistic [[verificationism]]'' of [[Willard Van Orman Quine]]. Quine's book ''[[Word and Object]]'' (p.&nbsp;3f) made famous Neurath's analogy, which compares the holistic nature of language and consequently scientific verification with the construction of a boat which is already at sea (cf. [[Ship of Theseus]]):

{{Quote|We are like sailors who on the open sea must reconstruct their ship but are never able to start afresh from the bottom. Where a beam is taken away a new one must at once be put there, and for this, the rest of the ship is used as support. In this way, by using the old beams and driftwood, the ship can be shaped entirely anew, but only by gradual reconstruction.}}

[[Keith Stanovich]] discusses this metaphor in context of [[memes]] and [[memeplexes]] and refers to this metaphor as a "[[Neurathian bootstrap]]".<ref>Stanovich, Keith E. (2004-05-15). The Robot's Rebellion: Finding Meaning in the Age of Darwin (1 ed.). University Of Chicago Press. {{ISBN|0-226-77089-3}}.</ref>

Neurath also rejected the notion that science should be reconstructed in terms of sense data, because perceptual experiences are too subjective to constitute a valid foundation for the formal reconstruction of science. Thus, the [[Phenomenology (philosophy)|phenomenological]] language that most positivists were still emphasizing was to be replaced by the language of mathematical physics. This would allow for the required objective formulations because it is based on spatio-temporal coordinates. Such a ''physicalistic'' approach to the sciences would facilitate the elimination of every residual element of metaphysics because it would permit them to be reduced to a system of assertions relative to physical facts.