Styles in Philosophy: the Case of Carnap
Gereon Wolters
University of Konstanz, Germany

1. Introduction
In order to get you in the right mood for what I am going to talk about in my paper I would like to start with two quotations everyone of you is familiar with. The texts were published only two years apart from each other. And both authors believe that what they are writing is philosophy. 
Erforscht werden soll nur das Seiende und sonst  – nichts; das Seiende allein und weiter  – nichts; das Seiende einzig und darüber hinaus  – nichts. Wie steht es um dieses Nichts? [...] Gibt es das Nichts nur, weil es das Nicht, d.h. die Verneinung gibt? Oder liegt es umgekehrt? Gibt es die Verneinung und das Nicht nur, weil es das Nichts gibt? [...] Wir behaupten: Das Nichts ist ursprünglicher als das Nicht und die Verneinung. [...] Wo suchen wir das Nichts? Wie finden wir das Nichts? [...] Wir kennen das Nichts. [...] Die Angst offenbart das Nichts. [...] Wovor und warum wir uns ängstigen, war ‘eigentlich’  – nichts. In der Tat: das Nichts selbst  – als solches  – war da. [...] Wie steht es um das Nichts? [...] Das Nichts selbst nichtet.
Or, you might do philosophy like this: 
A word which (within a definite language) has a meaning, is usually also said to designate a concept; [...] What, now, is the meaning of a word? What stipulations concerning a word must be made in order for it to be significant? [...] First, the syntax of the word must be fixed, i. e. the mode of its occurrence in the simplest sentence form in which it is capable of occurring, We call this sentence form its elementary sentence. The elementary sentence form for the word “stone” e.g. is “x is a stone”; in sentences of this form some designation from the category of things occupies the place of “x”, e.g. “this diamond,” “this apple”. Secondly [...].
Well, I think I can stop here. As I said, both texts are generally regarded as philosophical. At least they are read in philosophical seminars all over the world. They occur in the same text, the first as a quote, the second one serves to sharpen the intellectual tools to critically deal with the first. Although both texts are widely regarded as philosophical there are major differences that transcend in a substantial way the differences one may encounter between texts from the same period are found in textbooks of physics or psychology.
How do we account for these differences?  – My proposal in this paper is: they differ in style. 
I would like to go further and argue for the following three theses:(1) logical empiricism on the whole may aptly be characterized as a particular theoretical style of doing philosophy. (2) Carnap’s theoretical style differs, on the one hand, from that of other logical empiricists only with respect to the concrete implementations of that style. On the other hand, Carnap adds to his theoretical philosophical style a practical component not shared by all logical empiricists. It is Carnap’s style that remains unchanged in the flux of his philosophical positions. (3) I would like to argue that the theoretical style of logical empiricism is a suitable criterion for distinguishing between philosophy and non-philosophy. 

2. Philosophical Style 
The observation that the above quoted texts differ in style is true in a simple, almost superficial and trivial sense. The first text is a sort of dialogue, consisting of questions and answers. It carries an expressionist air with it. The second is written in a propositional, argumentative style and expresses a sensation of sober simplicity. It is not this kind of stylistic difference, however, that I am interested in. I am much more interested in something else: You may have noticed that I have quoted the first text in German. I did this not because I believe that every reader will be able to follow me. And certaily I do not want to embarrass those who don’t know much German or no German at all. I have read this text in German because the semantic content it conveys to the listener or reader remains essentially the same, whether he or she knows German or not. Indeed, as far as I am concerned personally, the first text has resisted so far all my attempts at understanding, whereas I am rather confident that I have grasped pretty well what the second is about. Whether this confidence is warranted or not may be left open here. 
You will have noticed immediately that I have in mind an understanding of the word “style” that ought to be distinguished from the usage we entertain in everyday educated conversation. So it seems to be suitable to first clarify the concept of style that I am proposing in this paper. I am not exploring the conceptual history here. Nor would I like to dwell on stylistic differences in a literary sense between the two texts. Such differences certainly exist and contribute to a certain degree to the concept of style I have in mind. But they do not do so in a decisive way. Instead of dealing with historical or literary aspects of the concept of style I would rather like to focus on two distinctions that seem relevant to me with respect to style in philosophy. 
In a general way I would like to characterize the word “style” as meaning the way or the form philosophical thoughts and attitudes are expressed linguistically. Now, the first distinction: we may distinguish between individual and collective style. Individual style may be ascribed to a text that cannot be reproduced by someone else in different words in the same sense. This distinction is, of course, derived from Kant’s concept of ‘genius’ in the Critique of Judgement. According to Kant “genius is the talent (the natural prodigy) which sets the rules for the arts.” And: “Genius is totally contrary to the spirit of imitation.” The genius himself is not aware of the rules he is setting. He is not able to think out rules of artistic activity and then apply them. Besides this, noone can learn the rules that render a work genial. This distinguishes the genius from the scientist and from the philosopher, for that matter. Even someone like Newton, whom he greatly admired is for Kant not a genius, because 
everything that he has presented in his immortal work on the principles of natural philosophy [...] can clearly be learned. [...] Newton could graphically show, and with the purpose of being follwed by others, not only to himself but to everyone else, all his steps that he had to make from the first elements of geometry to his great and deep inventions. (Kant, KU §47 (B184), my translation)
From this one can easily conclude that there can be no genius in philosophy, or, to put it differently, philosophy does not admit of individual style.
In German romanticism, e.g. with Novalis and Schleiermacher, we find again Kant’s conception that poetic style cannot be learned. But, much different from Kant, speculative philosophy now may be couched in an individual style (Frank 1992, ch. 1). The great speculative philosopher has now become someone who writes like the poet.
To the best of my knowledge it was Friedrich Albert Lange in his 1866 Geschichte des Materialismus who brought speculative philosophy and poetry together in coining the word “Begriffsdichtung” (conceptual poetry; Lange 1926, vol. 2, 429). It was no other than young Friedrich Nietzsche who took this concept from Lange, whom he much admired, and related Begriffsdichtung explicitly to metaphysics. In a letter from the end of April or the beginning of May 1868 that Nietzsche wrote to Paul Deussen he states that metaphysics is beyond the boundaries of knowledge. Those boundaries have been established 
in the course of the respective research since Kant, in particular physiologial research, [...] in such a certain and infallible way that apart from theologians, some professors of philosophy and the vulgus nobody has illusions about this any more. The realm of metyphysics, i.e. the province of „absolute“ truth, has been invariably alligned with poetry and religion. Whoever wants to know something contents himself with the consciousness of the relativity of knowing, as believed, for example, by all renowned scientists. Metaphysics thus belongs for some people [Nietzsche himself, of course, included] to the domain of emotional needs [Gemütsbedürfnisse], it is essentially edification [Erbauung]. On the other hand, metaphysics is art, namely the art of conceptual poetry [Begriffsdichtung]. It has to be remembered that metaphysics neither as religion nor as art has anything to do with the so called “True or being as such” [mit dem sogenannten „an sich Wahren und Seienden“].
Back to our two texts at the beginning. The one in German seems to me a good example of individual style. For reasons that might have already become clear, individuality of style cannot be a characteristic of the concept of style I am going to propose and to apply to logical empiricism. Rather, the concept of style in philosophy I am interested in is collective. This means that the concept of ‘style’ refers to the modus operandi of a collective of philosophers rather than refering to the supposedly unrepeatable expression that philosophical activity assumes or might assume with an individual philosopher. In other words: style is understood here as a set of explicit or implicit rules of which an individual philosophical work can be regarded as an application. 
The second distinction I would like to make is between subjective and objective style. Subjective philosophical style expresses conceptions of the world and of human existence in it, that are not intended to or, at least, are not justified in claiming general assent. A subjective philosophical style expresses what may be called a Lebensgefühl or “attitude toward life”, as Carnap translates this word (Carnap 1963, 4). You may share or, at least, understand a Lebensgefühl expressed in a philosophical work whose author entertains a subjective style  – and normally you are even invited to share or understand it  – but you may easily fail to do so. In case one fails, this failure is not necessarily due to one’s lack of intellectual resources. Rather a sort of required congenial emotional attitude is missing. A philosophical work written in an objective style, however, comes with the claim to be understood by anyone with the respective intellectual competence, i.e. a philosophical work in objective style claims to be  – in principle  – acessible to everyone ; and it claims also to be written in a manner to achieve that goal. 
It is clear that the distinctions made here about the concept of style are not independent of each other. Collectivity presupposes objectivity, and subjectivity precludes both objectivity and collectivity. In my view quite a few philosophers of the tradition subscribe to a more or less collective and objective style in philosophy.

2. Philosophical style in logical empiricism, particularly with Carnap
This holds in the most perspicuous way for logical empiricism. I am not aware of explicit declarations to this effect among logical empiricists, but it can be inferred easily from a host of respective contexts. There are several programmatic utterances that all refer to a collective and objective way of doing and writing philosophy, the most perspicuous, for some even notorious, is the manifesto “Wissenschaftliche Weltauffassung  – Der Wiener Kreis” of 1929, “essentially written by Neurath and toned down by Hahn and Carnap”, in order to make it more acceptable to Schlick to whom it was dedicated. Here one finds the outlines of a collective and objective style of doing philosophy. It is described in the following way
The scientific world conception is characterized not so much by theses of its own, but rather by its basic attitude, its points of view and direction of research. The goal ahead is unified science. The endeavour is to link and harmonize the acievements of individual investigators in their various fields of science. From this aim follows the emphasis on collective efforts, and also the emphasis on what can be grasped intersubjectively; from this springs the search for a neutral system of formulae, for a symbolism freed from the slag of historical languages; and also the search for a total system of concepts. Neatness and clarity are striven for, and dark distances and unfathomable depths rejected.
Although the word “objectivity” is not explicitly mentioned here, it is clear that the “emphasis on what can be grasped intersubjectively” and other things referred to in this quote point to the concept of objectivity. A closer look at early writings of Carnap reveals that the objectivity of knowledge is at the very heart of Carnap’s thinking. This has recently been shown convincingly, particularly with respect to the Der logische Aufbau der Welt by Alan Richardson. Apart from this point, it seems clear to me that the sort of collective work in philosophy, required according to the above quote, must take objectivity-based intersubjectivity as a necessary condition. I think that the whole of Carnap’s philosophy can be regarded as the continual and progressive effort to arrive at a form of philosophical language that garantees objectivity. 
After the Aufbau, conformity to the rules of logical syntax became a necessary condition for objecitvity and, thus, of sensibly doing philosophy. As we know Carnap later added semantics, and also thought  – at least after Kuhn’s Structure of Scientific Revolutions  – of the socio-historic pragmatics as something that should not be neglected. The details of all these later developments are not relevant to my argumentation, though; I am only interested in making clear that objectivity is at the very heart of Carnap’s philosophical thinking.
So, I am restricting myself to the finest example of applying the rules of logical syntax. One finds it in Carnap’s famous 1931 essay “Überwindung der Metaphysik durch logische Analyse der Sprache”. In this essay, whose historical background has been elucidated in Michael Friedman’s splendid paper on Carnap and Heidegger (Friedman 1996) and that has been clarified further by Gottfried Gabriel (2003), Carnap gives among other things a critical analysis of a little anthology of sentences taken from Heidegger’s Was ist Metaphysik?, a text that precisely lacks the sort of objecitivity that Carnap and the other logical empiricists require. The result of his analysis is that this text  – although grammatically correct  – is senseless metaphysics because it violates basic rules of the logical syntax of language. This violation of logical syntax includes (1) the mistake of taking “nothing” as a word denoting an object (Gegenstandsname) and (2) in introducing a senseless new word, i.e. the verb “nichten”. Although Heidegger’s text and metaphysics in general is thus senseless, it is in Carnap’s eyes not nonsense. Although it does not contain theoretical content, Carnap admits that it is a powerful, though inadequate, expression of Lebensgefühl (Carnap 1931, 238). The adequate expression of Lebensgefühl would be in the arts. Metaphysics pretends to have
the form [...] of a system of statements which are apparently related as premises and conclusions, that is, in form of a theory. [...] In reality, however he [i.e. the metaphysician] has not asserted anything, but only expressed something, like an artist. That the metaphysician is thus deluding himself cannot be inferred from the fact that he selects language as the medium of expression and declarative sentences as the form of expression; for lyrical poets do the same without succumbing to self-delusion. But the metaphysician supports his statements by arguments, he claims assent to their content, he polemicizes against metaphysicians of divergent persuasion by attempting to refute their assertions in his treatise. Lyrical poets, on the other hand do not try to refute in their poem the statements in a poem by some other lyrical poet; for they know they are in the domain of art and not in the domain of theory.
What strikes me here is the similarity with the quote from the young Nietzsche about Begriffsdichtung. And, in fact, Carnap sees Nietzsche as someone who thought along the same lines. He closes „Überwindung“ by saying that 
the metaphysician who perhaps had artistic talent to the highest degree, viz. Nietzsche, almost entirely avoided the error of that confusion [i.e. between art and philosophy]. A large part of his work has predominantly empirical content. We find there, for instance, historical analyses of specific artistic phenomena, or an historical-psychological analysis of morals. In the work however, in which he expresses most strongly that which others express through metaphysics or ethics, in Thus Spake Zarathustra he does not choose the misleading theoretical form, but openly the for of art, of poetry. 
So much for objectivity and collectivity as central features of the philosophical style of logical empiricism in general and of Carnap in particular.
At this point one may ask, why should it be adequate to call ‘style’ the distincitive feature of Carnap’s philosophy, and of logical empiricism in general. Why not just call it ‘method’? There are several reasons for this. The first one is that logical empircicism is all about language and not about the world. This is a result of strictly pursuing the objecitvity criterion. All its subsequent implementations, from the epistemological approach of the Aufbau to his later semantics can be understood as progressive implemetations on the part of Carnap of the two requirements of logico-empiricist philosophical style, i.e. collectivity and objectivity. Collectivity and objectivity are, secondly, the invariants of Carnap’s philosophical work at every stage of its development. These two requirements are the benchmark of judging everything that claims to be philosophy. In an earlier paper, I have referred to them as the requirements of clarity and critical cooperation (Wolters 1993, 10). So, the point is that, in judging whether something may rightly claim to be philosophy, it is not the content that counts, but rather the style. Philosophical content changes and must change in order to realize progress. What remains unchanged are the requirements of how to do philosophy, i.e. the requirements of clarity and critical cooperation, or the requirements of collective and objective style in philosophy. Looking back in his “Intellectual Autobiography” Carnap, then, states with respect to the Vienna Circle: “The common spirit was one of co-operation rather than competition. The common purpose was to work together in the struggle for clarification and insight” (Carnap 1963, 21).  – It is for these two reasons that it seems to be adequate to designate as “style” the unspecified requirements of objectivity and collectivity of philosophical language. Their changing implementations may be called “method”.
The third reason why I would like to designate Carnap’s approach as ‘style’ rather than ‘method’ is that Carnap as early as in the preface to the Aufbau, i.e. as early as 1928, characterized the general outlook of his philosophical enterprise as ‘style’. 
Therefore, it is no wonder that Carnap never changed his mind with respect to Heidegger’s philosophy, or at least with respect to his criticism in his “Überwindung”. Thirty-six years later, in an interview that he gave to Willy Hochkeppl in 1967, when asked whether he retained his strict criticism of metaphysics, he answered the following: 
Perhaps not with the same rigor. I believe, however, that the essentials (der Kern) of our earlier critique remain. I would, for example, with respect to Heidegger’s statements say, as I did earlier that we reject them as completely ununderstandable. It does not make an essential difference whether we call them senseless  – as we did in those days  – or, as we do today, use the more cautious denotation “without cognitive content”, or, as I said earlier in another context, whether we designate them as superfluous in the complete system (Gesamtsystem) of the postulates of science. We would also say similar things with respect to certain Neo-Hegelians these days.

4. Carnap’s Philosophical Style: the Practical Component
I hope to have convinced you by now that the approach of logical empiricism in general and of Carnap’s philosophy in particular might aptly be called ‘stylistic’. It is time now to add to the two features of objectivity and collectivity and their special implemenations that so far constitute the style of Carnap a third one. Whereas objectivity and collectivity express theoretical attitudes, this third feature is practical. 
Before dealing with this feature one has to look at Carnap’s concept of knowledge (Erkenntnis). As one can easily gather from many contexts but most explicitly from the last part of the Aufbau (“Tasks and Limits of Science”), knowledge is by definition what Carnap calls “conceptual knowledge” (begriffliche Erkenntnis). Knowledge is opposed to various forms of intuition. Science and philosophy can only deal with conceptual knowledge, that is characterized by being true or false. In modern terminology we might say: knowledge, by definition, is always propositional. For Carnap 
there is no way from the continent of rational knowledge to the island of intuition, whereas we have found a way from the country of empirical knowledge to the country of formal knowledge, which therefore demonstrate to belong both to the same continent. From this follows: [...] irrational intuition and religious belief cannot be called “knowledge” (Erkenntnis). 
This position seems very reasonable to me with respect to a discussion in current German philosophy about literary forms of philosophy. Here the question is, whether there can be “non-propositional knowledge in philosophy”. Or, to put it differently, whether philosophy is essentially an argumentative enterprise, expressed in propositions, or permits of other literary forms. To be sure, in the history of philosophy we see a great variety of literary forms. Carnap’s requirement that in the last analysis statements must have a claim to truth in order to qualify as philosophical knowledge seems adequate to me. If you admit everything as knowledge, then nothing is really knowledge. This does not mean that Carnap would belittle or reject intuitive, i.e. non-propositional, forms of acquaintance with the world. 
Let us now turn to the practical component of Carnap’ s philosophical style. The first thing we have to notice here is that Carnap does not restrict his concept of intuition to approaches to philosophy that are poetic in some way or other. Let us consider questions like this: Why should one philosophize in an objective and collective way? Or, why must one “banish the whole of metaphysics from philosophy” (Carnap 1928, XIX)? Or, why is one obligated to take “a common scientific basic attitude (Grundeinstellung)” (loc.cit., XVIII). Or, why should one “take a practical stand” (Carnap 1934, 257). In short, one may ask Carnap why one should strive for certain goals or values. Carnap’s answer is simple and unambiguous, or better: it is a non-answer: “Here no proofs are possible, there is only influence and education” (loc. cit., 258). Goals and values rest solely on intuition. Knowledge, i.e. conceptual, propositional knowldege or rational argument, is unattainable here. Or, as Carnap puts it as late as in the section on “Values and Practical Decisions” of the Intellectual Autobiography: “for factual questions arguments of factual evidence will be offered; whereas persuasion, educational influence, appeal, and the like will be brought to bear upon decisions concerning pure value questions” (Carnap 1963, 81). In short, as we all know, Carnap as well as most other logical empiricists, is a non-cognitivist with respect to value statements. Of course, this does not mean that Carnap was not interested in moral problems. Rather he emphasizes that he “always had an intense interest in moral problems, both those concerning the life of individuals and, since the First World War, those of politics” (loc. cit., 82). And from his biography we know furthermore that his moral interest was not only theoretical. As Hochkeppel rightly says: “In marked contrast to the great theoreticians of praxis and the rhetoricians of responsibility (without responsibility) [...] Carnap, throughout his life, unmediatedly acted where words could not help any more: in manifestos against the war in Vietnam, in working with an organization of American blacks, finally, with a visit to jail in Mexico in order to help three Mexican colleagues imprisoned for political reasons” (Hochkeppel 1993, 154f., my translation). This visit in Mexico, by the way, took place only a few months before his death. It is significant in this respect that  – according to Stegmüller  – the last picture taken of Carnap shows him in a group of civil rights activists.
So the question arises, why a man so conscious of the moral and political problems around him and so active in doing his part to alleviate suffering did not take into consideration an approach to problems of norms and values that does not exclude them completely from the realm of rational discourse, i.e. why does he not envisage an approach that uses argumentative means rather than just “persuasion, educatioal influence, appeal, and the like”. He never, ever  – as far as I can see  – confronts himself with the question, why the realization of certain norms or values ought to be furthered by those educational means and other norms and values do not deserve this. 
In the same vein he does not ask himself why 
nearly all of us [in the Vienna Circle] shared the following three views [..., heavily value laden views I would like to add]: The first is the view that man has no supernatural protectors or enemies and that therefore whatever can be done to im prove life is the task of man himself. Second, we had the conviction that mankind is able to change the conditions of life in such a way that many of the sufferings of today may be avoided and that the external and the internal situation of life for the individual, the community, and finally for humanity will be essentially improved. The third is the view that all deliberate action presupposes knowledge of the world, that the scientific method is the best method of acquiring knowledge and that therefore science must be regared as one of the most valuable instruments for the improvement of life.“ (Carnap 1963, 83)
For these three views for which there was no designation in Vienna, Carnap later in America used the term “scientific humanism”. I would like to call this humanistic attitute the practical component of Carnap’s philosophical style. So, in my view, the theoretical components of objectivity and collectivity, together with its subsequent implementations and the practical component of scientific humanism, form, what I would like to call, Carnap’s philosophical style. To Carnap’s case applies more than to most others, Buffon’s famous dictum before the French Académie de Sciences on August 25, 1753: “Le style est l’homme même”.
But contrary to Carnap I regard his non-cognitivism not as a virtue but rather as a vice. I think it has its roots in some sort of all-or-nothing radicality of Carnap’s character. Thomas Mormann in his fine popular biography of Carnap writes:
Carnap had little inclination to leave things open or indulge in compromises which were perhaps not heroic, but sometimes render life easier. In this respect he was a difficult person. His standards with respect to clarity and precision were often to high for real life. When Maria Reichenbach proposed to him once a little white lie (Notlüge) he responded with a smile: “Maria, you have a criminal character”.
Carnap’s worldview had a Cartesian air about it. He thought in clear and distinct concepts and distinctions: Everything was either the one or the other: either science or metaphysics. Sentences were either analytic or synthetic, questions either ‘extern’ or ‘intern’, judgments were either judgments about facts or value judgments. He opposed nuances (Zwischentöne), imponderabilities and unanalyzable transitions. The pragmatic idea of a ‘continuous’ transition between facts and values [as proposed by Putnam] Carnap would have certainly rejected. His unconditional and rigorous striving for clarity and objectivity in the realm of knowledge found its equivalent in the political sphere in his vision of a world without obscurantism, oppression and violence, a world in which human beings could reasonably work and live together.“ (Mormann 2000, 36)
This radicalism prevented Carnap from acknowledging what he himself almost certainly did when he thought about values. It prevented him from noticing that also he reasoned in some way or other about values, although such reasoning is most of the time not about truth or falsehood but rather about the more or less plausible, adequate or desirable. He failed to realize that there are modes of reasoning and argument which are not as stringent as the arguments in the domain of theory are expected to be. He ignored that there can be rational orientation in the domain of praxis even if one remains agnostic with respect to the existence of a transcendent realm of values. He did not notice that there are even large areas in the realm of theory where the results of reasoning and argument have only more ar less plausibility  – without the consequence that one has to give up propositionality. In short, Carnap did not realize that rationality, actually, is not restricted and, furthermore, should not be restricted to the domain of theory. 

References
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