Carnap (1891-1970), like other members of the Vienna Circle, was influenced both by the positivism of people like the physicist Ernst Mach (1838-1916) and by Wittgenstein. Wittgenstein’s influence came first from the Tractatus, but also from the somewhat different views he held after his return to philosophy in the late 1920s and that he conveyed in meetings with the Vienna Circle when he returned to Vienna for visits after he’d taken up a fellowship at Cambridge.
Carnap published his second major work, Logische Syntax der Sprache (Logical Syntax of Language), in 1934, and his contribution to the first volume of the American journal Philosophy of Science presents ideas found in it. Around the time his book was published, Carnap delivered a series of lectures in London, which were later published as Philosophy and Logical Syntax (London: Keagan Paul, Trench, Trubner & Co., 1935). The second part of your assignment is a short account of these lectures and of discussions around the same time. The account of Carnap’s lectures by Maund and Reeves covers much of the same ground as Carnap’s article—and does so in a very terse way—but it incorporates an important difference in terminology. Where Carnap’s American translator had used “connotative” to render the German inhaltlich, Carnap’s lectures use “material” instead—and it is the latter translation that has become standard.
• The most characteristic view of positivists is the rejection of metaphysics. Carnap presents his form of this on pp. 5-8. It can be traced through positivists like Mach and Auguste Comte (1798-1857), the inventor of sociology, back to Hume. But, by contrast with earlier positivists, Carnap, like Wittgenstein, rejected metaphysics not as speculative but as meaningless. He suggests a difference between his views and Wittgenstein’s in his comments on the quotations from the Tractatus (4.112 and 6.54) on pp. 7f of “On the Character …,” but the difference is less when what Carnap says is compared to Wittgenstein’s views of the late 1920s and early 1930s. At that time, Wittgenstein, too, saw philosophy as concerned with syntax, and it’s easy to think of the views Carnap presents here as his own way of developing ideas he learned from Wittgenstein.
• He probably was influenced by Wittgenstein in another respect. The standard grounds for holding metaphysics to be meaningless on the part of the Vienna Circle and others at the same time with similar views—the term “logical positivist” tends to be used for such people—is the “principle of verification” according to which the meaning of a claim is to be found in its “mode of verification.” Metaphysics was meaningless because it claimed to go beyond experience and its claims could, in principle, have no verification in experience. This idea can be traced back to the British empiricists, and especially Hume, but in the form advanced by the logical positivists, it seems to have been due to Wittgenstein around 1930. The idea is not explicitly stated in Carnap’s article but appears prominently in the report of the lectures (pp. 42f).
• One of Carnap’s own contributions lies in his distinction between the formal and material modes of speech. Getting a sense of this distinction and its significance is your chief task in digesting Carnap’s article, and a substantial part of our discussion will be devoted to the double-column tables on pp. 13-16. The distinction makes only a brief appearance in the report of the lectures (pp. 44f), but has a more prominent place in the lectures as published, with the example in the report appearing in the following table (Philosophy and Logical Syntax, p. 61):
| 1. Real object-sentences. |
2. Pseudo-object-sentences. Material mode of speech. |
3. Syntactical sentences. Formal mode of speech. |
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| (Empirical Science) | (Philo | sophy) | |||
| 1a. | The rose is red. | 1b. | The rose is a thing. | 1c. | The word ‘rose’ is a thing-word. |
| Q1(a) | Q2(‘a’) | ||||
| 2b. | The first lecture treated of metaphysics. | 2c. | The first lecture contamed the word ‘metaphysics.’ | ||
| 3a. | Mr. A visited Africa. | 3b. | This book treats of Africa. | 3c. | This book contains the word ‘Africa.’ |
| 4a. | The evening-star and the earth are about equal in size. | 4b. | The evening-star and the morning-star are identical. | 4c. | The words ‘evening-star’ and ‘morning-star’ are synonymous. |
• You should also notice how Carnap uses the distinction of formal and material modes as a way of overcoming or undermining philosophical controversies. This aim is characteristic of Carnap and appears also in the other chief distinction of the article, that between “assertions” and “proposals.” The latter distinction is closely related to the ideas in 6.341 of the Tractatus. That is, assertions can be made only within a given framework but one might propose one framework or another on what the logical positivists called “pragmatic” grounds—i.e., as a simpler or more convenient framework within which to make assertions about a given subject matter.