¹ Studies in philology 27.553 (1930). The summary which follows above is stated so as to bring out the accord with the Viennese conclusions (see below).

² R. Carnap, 'Ueberwindung der Metaphysik,' Erkenntnis 2.219 (1931); also in a French translation, which I have not seen, La science et la métaphysique, Paris 1934 (= Actualités scientifiques, vol. 172); 'Die physikalische Sprache,' Erkenntnis 2.432 (1931); also in an English translation, which I have not seen, The unity of science, London 1934 (= Psyche miniatures, General series, No. 63); 'Psychologie in physikalischer Sprache,' Erkenntnis 3.107 (1932); 'Les concepts psychologiques,' Revue de synthèse 10.45 (1935); Logische Syntax der Sprache, Vienna 1934 (= Schriften zur wissenschaftlichen Weltauffassung, 8); Philosophy and logical syntax, London 1935 (= Psyche miniatures, General series, No. 70).

O. Neurath, 'Physikalismus,' Scientia 50.297 (1931); 'Physicalism,' The monist 41.618 (1931); 'Soziologie und Physikalismus,' Erkenntnis 2.393 (1931); Einheitswissenschaft und Psychologie, Vienna 1933 (= Einheitswissenschaft, Heft 1); Le développement du cercle de Vienne, Paris 1935 (= Actualités scientifiques, vol. 290).

³ This example is modeled on Carnap's examples in Philosophy and Logical Syntax, 16ff.; for a thoroughgoing analysis see Weiss's article on solipsism, Psychological Review 38.474 (1931).

⁴ Compare Carnap, 62, who uses thing-word for noun. The term noun (or thing-word), of course,—though Carnap does not mention this—must then be defined, for English grammar, and the term word for language in general, as technical terms of linguistics; this definition, moreover, must be made in terms of the postulates, undefined basic terms, and earlier definitions of linguistics—not by definitions of meaning and not in metaphysical terms. Thus, a word is the smallest meaningful unit that can be spoken alone. In English, a noun is a word which enters centrally into endocentric phrases with preceding adjective modifiers, serves as an actor with a finite verb, as the goal of a verb or preposition, and as a predicate complement, appears always in one of two sub-classes, singular and plural, and joins with the suffix [-ez, -z, -s] to form an adjective. Carnap, so far as I have found, nowhere mentions the fact that the discourse of logic presupposes descriptive linguistics and uses the technical terms of this empirical science. The complex linguistic background of logical and mathematical statement is generally ignored by philosophers and logicians; an informal outline of it will be found in Philosophy of Science 2.499 (1935); more formally in my Language, New York 1933, chapters 2 to 16.

⁵ Max F. Meyer, The Psychology of the Other One, second edition, Columbia, Missouri, 1922.

Albert Paul Weiss, A Theoretical Basis of Human Behavior, second edition, Columbus, 1929.

⁶ In Der logische Aufbau der Welt (Berlin 1928) 81, Carnap mentions Watson and, of all people, Dewey, as behaviorists; in Erkenntnis 3.124 (1932) he mentions a German translation (1930) of Watson's Behaviorism. Neurath, Einheitswissenschaft 20, analyzes a paragraph of this German translation and finds that Watson's use of the terms good and bad violates the rule of physicalism; from this, Neurath seems to draw the conclusion that Watson and all other American students fail to satisfy the demand of physicalism. As a matter of fact, Watson has in the original text (New York, 1924, page 41) the words ‘good’ and ‘bad’ in quotation marks plainly as citations from everyday speech. Moreover, without prejudice to Watson's merits as an investigator and as a popularizer, his Behaviorism has the familiar faults of popularization and cannot be seriously used as Neurath uses it. In order to compare the Vienna students' physicalism with serious American work, one must study the latter as well as the former.

Yet Neurath's point is not without interest. In correcting the passage from Watson, he can find only an ethnological translation for the words good and bad; meanwhile Weiss, Theoretical Basis 102ff., 446ff. has given a strictly physical translation of these words in terms of the variability of a system.

Neurath proposes (Einheitswissenschaft 17) to designate his group as Behavioristiker and their discipline as Behavioristik, in contrast with the American behaviorists (Behavioristen) and behaviorism (Behaviorismus). The distinction is illusory, since it is based upon lapses from exactitude, real or apparent, such as are to be found also in the writings of the Vienna circle. We shall do well not to insist upon such deviations, but rather to concentrate upon the necessary and sufficient rule: Every scientific statement is made in physical terms. The most perfect formulation of this, so far as I know, and the best exemplification, are to be found in Weiss's Theoretical Basis. As to the name behaviorism (which Weiss disliked), it is in many ways objectionable and has been adopted by writers who fail, not only in the way of lapses, but in actual operation, to fulfil the essential demand (Carnap, Erkenntnis 3.125, 'unechter Behaviorismus'). Physicalism is a much better word. We should stress our agreement as to the essential point and join in defending it from misinterpretation. Note, for instance, the striking accord between Neurath's 'zweites Menschlein' (Einheitswissenschaft 16) and Weiss's early essay, ‘The mind and the man within’, Psychological Review 26. 327 (1919).

⁷ I. P. Pavlov, Conditioned Reflexes, translated by G. V. Anrep, Oxford 1927.

⁸ L. Hogben, The Nature of Living Matter, London 1930.

⁹ P. W. Bridgman, The Logic of Modern Physics, New York 1932; profession of mentalism (x); operational principle (5); application (28, an excellent example, whose very wording agrees with Carnap); 56 (an important point); 94; 130; 139; 153; 166; 203.

¹⁰ Printed summary on a leaflet, Kiel 1921; the original dissertation is typewritten only, and I have not seen it.

¹¹ Here we must include the doctrine predominant among Russian scholars. For example, R. Shor's article on Linguistics in the Encyclopedia (Bol'shaja sovetskaja enciklopedija, 65.392, Moscow 1931) represents not ‘materialism’ in any strict sense, but rather the normal nineteenth-century dualism.

¹² Karl Pearson, The Grammar of Science³ 1.197 (London 1911).