Table Of ContentPROTOCOLS, TRUTH
AND CONVENTION
Thomas Oberdan
Amsterdam -Atlanta, GA 1993
" - - - - - - - - - - ---"'---- - -
-
Acknowledgements
The following essay is a revised version of the dissertation I defended
at Indiana University in the Fall of 1989. I especially wish to acknowledge
the members of my committee who helped see the project through to
completion: Linda Wessels, who encouraged an otherwise hopeless endeavor;
Rick Creath, who re-kindled my interest in the topics of this essay and has
since become an invaluable interlocutor; Michael Friedman, who oversaw my
efforts stage-by-stage and forced me to glimpse insights I would otherwise
have missed; and Michael Dunn, who patiently imparted logical corrections
whenever I bungled some crucial detail. Don Howard of the University of
Kentucky, Rudolf Haller and Werner Sauer of Graz provided detailed
comments of earlier drafts that vastly improved my understanding and --I
hope-- the final product. Most of the suggestions of all who commented
have been incorporated. The result is, nonetheless, my own responsibility.
At an earlier stage, Robert Cohen, Brian McGuinness, and Henk Mulder eased
my access to crucial research resources, without which this essay could not
have been written.
I would be remiss if I did not mention Angelina Oberdan, who tried to
understand that I was not just playing computer games (at least not all the
time).
And, finally, there was Alberto Coffa. I regard it as a rare privilege to have
once been his student, to have sipped coffee, relished Sa::hertorte, and argued
the fine points of Wiener Kreis philosophy with him. The current essay is the
tangible product of his efforts to teach me; to his memory I dedicate this
work.
Thomas Oberdan
Clemson, South Carolina
July 7, 1992
CONTENTS
I. PRELUDE TO PROTOCOLS
1. The Pre-History of Protocols 1
2. Anticipations of Protocols 9
II. PROTOCOLS IN EARLY PHYSICALISM
1. The Early History 15
2. The Pragmatics of Protocols 23
3. Neurath's Proposal 30
4. Conventionalism and Protocols 34
ill. FOUNDATIONS AND TRUTH
1. Truth in Physicalism 41
2. The Right Wing's Response 48
3. Neurath's Complaint 56
IV. METALOGIC AND TOLERANCE IN THE LOGICAL SYNTAX
1. The Problem of Elucidations 65
2. Pseudo-Object Sentences 76
3. Truth and the Antinomies 85
V. CONVENTIONALISM AND THE APPLICATION OF LANGUAGE
1. Conventionalism in the Right Wing 92
2. The Critique of Philosophical Pseudo-Theses 98
3. The Application of Language 104
4. Truth and Verification 112
VI. ANALYTICITY AND TRUTH
1. 'Analytic' in Language I 119
2. Semantic and Syntactic Conceptions of Truth 124
3. Paradoxes and Hierarchies 131
4. Confirmation and Correspondence 135
Bibliography 143
I. PRELUDE TO PROTOCOLS
1. The Pre-History of Protocols
The celebrated controversy over protocol sentences, that divided
the group of mathematicians, social scientists, and philosophers known
as 'The Vienna Circle', is as philosophically significant today as it was
fifty years ago. In part, this is due to the rich intellectual legacy
contemporary analytic philosophy inherited from the early Logical
Positivists. To a greater extent, however, continued interest in the
protocol debate is due to the fact that many of the philosophical
questions it raised have yet to be satisfactorily answered. The dispute
was triggered by a limited disagreement over the syntactic form and
epistemological function of 'protocol sentences': paradigms or
idealizations of the records and reports of scientific observations. But
soon the discussion exploded into a wide-ranging controversy expressly
involving fundamental issues in logic, methodology, and philosophy of
science, sundering the Circle into two theoretically opposed factions.
The group that initiated the discussion was led by Otto Neurath, the
originator of the most radical form of Physicalism, and Rudolf Carnap,
whose researches into the syntactical nature of language provided their
analysis with its logical foundations.1 Opposed to their view was the
conception of the Circle's Right-Wing, publicly represented by Moritz
Schlick, who was encouraged by his friends Ludwig Wittgenstein and
Friedrich Waismann. Since many of the issues they addressed appear
at the forefront of philosophical discussions today, it is no wonder that
contemporary philosophers still seek wisdom and insight in the writings
of the Circle members on the subject of protocols. But the lessons that
have been drawn from the controversy are of questionable value since
they are founded on shallow conceptions of the opinions and viewpoints
that figured decisively in the ensuing clash. Without denying the
1 Some would say that Neurath's 'Radical' Physicalism was centered on an
indeterminacy thesis similar to Duhem's and, much later, Quine's. (Neurath
1983, p. 105) In this respect, Neurath's form of Physicalism differs from
Carnap's in its emphasis on indeterminacy themes. For this reason, the term
'Physicalism' is used throughout this essay to denote what is common to both
Neurath's and Carnap's conceptions.
2 3
significance of the purely epistemological questions raised in the debate - to the age-old problem of the observational basis of scientific knowledge.
-especially concerning the epistemic warrant of scientific claims, the role Though largely forgotten today, it is worthwhile recalling that the
of observation in theory confirmation, the theoretical control of Metalogic Thesis was the first precept to emerge from Carnap's recently
experimentation, and so forth-- it is a major theme of this essay that inaugurated syntactical researches. According to this thesis,
much of their philosophical substance derives from the underlying philosophical problems are --in so far as they are meaningful at all-
conceptions of language. metalinguistic issues concerning the analysis of language and its logical
Instead, two chief issues are usually identified as the focus of the features. The immediate result was the transformation of the traditional
controversy. First, there is the epistemological one provoked by the problem of the epistemological basis into one dealing explicitly with
development of fallibilism at the hands of the Physicalists. Loosely linguistic forms, called 'protocol sentences', that express the results of
speaking, this is the thesis that all claims are corrigible and none are scientific observation.
immune to the possibility of revision. The Physicalists offered this view In a sense, the question of the syntactic analysis of protocol
in explicit opposition to the Circle's (and especially the Right-Wing's) sentences was a re-orientation --under the aegis of the Metalogic Thesis-
traditional foundationalism: roughly, the idea that the credibility of all of the discussion of the epistemological basis in Carnap's book, The
claims depends on their support by a select class of incorrigible ones that Logical Construction of the World. The point of Carnap's detailed
describe immediate experience. Attached to these epistemological constructions in the Aujbau --the more familiar name of the work-- was
antitheses were two equally opposed conceptions of truth. The to display the epistemological relations obtaining among various types
fallibilists, in their hurried flight from foundationalism, also deserted the of objects of knowledge. The question of the basis assumed the form of
correspondence notion of truth with which it had, in the minds of most an inquiry into the fundamental entities from which all possible objects
Circle members, always been associated and, at least for a short time, of knowledge could be constructed by purely logical means.2 Carnap
seemed to believe that truth is nothing but consistency with a given body distinguished three basic types of entities with which any constructional
of statements. When Schlick countered the Physicalists' proposals with system must deal: psychological, physical, and cultural objects. (1928,
the homely cliche that truth is correspondence with the facts, mediated Secs. 18, 23) The question of the basis, then, is the question of which
by indubitable reports of immediate experience ("Konstatierungen"), it of these types of objects is to serve as the starting-point from which the
appeared that correspondence was defensible only to the extent to which others are to be constructed. The chief motive behind Carnap's efforts
the basis of knowledge is certain. From this initial clash, there emerged was, of course, the epistemological one of displaying the relations of
two diametrically opposed positions: the Physicalists' combination of epistemic primacy obtaining among the various object types; thus a key
fallibilism and coherence, and the Right-Wing's, which founded desideratum of the basis was that it should be comprised of those entities
correspondence on the doctrine of certainty. (Feyerabend 1981, pp. 48- through which objects of the remaining types come to be known. (1928,
54; Scheffler 1982, pp. 92-124) Sec. 54) To begin with, Carnap argued, physical and psychological
If only things were this simple! But the fact of the matter is that the objects are mutually reducible. Physical objects are reducible to
issues in the protocol sentence controversy go far deeper than the psychological ones in so far as statements about physical things are
competition between fallibilist and foundationalist epistemologies. To verifiable in terms of sensory qualities. (1928, p. 92) Moreover,
treat the controversy merely as a rivalry between two opposed positions presuming the (yet to be proven) empirical hypothesis that to every
with contrasting ideas about acceptance, and similarly disagreeing psychological process there is a parallel process in the brain, conscious
notions of truth, is to overlook the substance of both the philosophical states are in principle reducible to states of the brain. (ibid.) Further
positions involved, and neglect the deep issues which motivated the
better-known moves made by the leading players in the debate.
To mention just one obvious point at which purely logical
2 The 'purely logical means' employed in the Aujbau for structuring the
considerations impinged on the epistemological issues in the dispute, the
elementary experiences consist primarily of the resources of logic and
very notion of protocols arose when Carnap applied one of the key
mathematics plus the basic relation of 'remembered similarity'. (1928, Secs.
precepts of his emerging analysis of language --the Thesis of Metalogic--
153-5)
4 5
granting that cultural objects (e.g., the concept of the Renaissance) are
The autopsychological basis is also called solipsistic. We do
reducible to psychological ones (though not conversely), it appeared that
not thereby subscribe to the solipsistic view that only one
the psychological and the physical domains of objects were equally well
subject and its experiences are real, while the other subjects
suited to serve as the basis. (1928, Sec. 57) Moreover, the choice of a
are nonreal. (1928, p. 101)
physical object basis would have the added advantage that it would be
founded on the only object domain "which is characterized by a clear
Thus, since Carnap's constructional system utilizes the method and form
regularity of its processes". (1928, p. 95)
of solipsism, while abjuring its central thesis, it is properly described as
Yet the adoption of a physical basis would obscure the system's goal
methodological solipsism. (1928, p. 102)
of revealing the relative epistemic primacy of the constructed objects.
These considerations lead quite naturally to the question of
If the psychological domain is subdivided into the autopsychological,
whether a constructional system based on the autopsychological would
consisting of 'for-me' entities, and the heteropsychological, comprised
not be subjective, for how can a system constructed on such a basis
of the mental contents of other subjects, then there are two reasons why
account for the objectivity or, (equivalently) intersubjectivity of scientific
the epistemic aims of the constructional system are best served by the
knowledge? Carnap thought the solution to this problem was to be
choice of an autopsychological basis. First, the heteropsychological
found in the difference between the form and content of experience.
objects can only be constructed with the mediation of physical ones.
Although the material or content of the experiences of distinct
Secondly, the decision to employ an autopsychological basis results in
indi~id~als is inc?mparable, for it is simply absurd to suppose that the
a considerably smaller initial domain. (1928, Sec. 64) Accordingly,
qualitative sensations present to two different consciousnesses could be
Carnap adopted an autopsychological basis for the construction system,
compared, their structural properties are nonetheless analogous.
taking momentary cross-sections of sensations, unanalyzed into distinct
sense modalities, as the 'elementary experiences' of which all objects of
Now, if science is to be objective, then it must restrict itself to
knowledge are to be constituted. (1928, Secs. 67-8)
statements about such structural properties, and, as we have
Although Carnap's choice gives the impression that his construction
seen earlier, it can restrict itself to statements about structures
system follows the lines of classic postivist or sensationalist
since all objects of knowledge are not content, but form, and
philosophies, he explicitly disavowed this characterization on the since they can be represented as structural entities. (1928, p.
grounds that it is purely extra-systematic, belonging not to the 107)4
construction system proper but to the domain of metaphysics. (1928,
Sec. 60) Moreover, since no distinction between the real and the Nor was Carnap the first Circle member attracted to the enticing duality
fictional, or even between the different subjects of sensation can be of f~rm and_ co.ntent_. In particular, this distinction was already tacit in
drawn prior to the construction of the system, no commitment to Montz Schlick s epistemological writings and was soon to become the
solipsism can be inferred from the choice of an autopsychological basis. focus of his thought during the early years of the Circle.
(1928, Sec. 64) While constructional systems founded on As early as 1918, Schlick had introduced his doctrine of implicit
autopsychological bases share the method of solipsism, they need not definitions in his General Theory of Knowledge to counter both
represent a commitment to its philosophical thesis. 3
I use its name as a convenient abbreviation to speak about my own
3 Coffa has shown that Carnap's neutrality in the Aujbau is seriously experience." (Carnap 1928, (German ed.), p. 220)
mitigated by his claim that his distinction between basic elements and
1constructed objects corresponds to Frege's dichotomy between 'saturated' and
'unsaturated' expressions, with the implication that "unsaturated expressions 4 Since 'form' is interpreted in the Aujbau in terms of the empirical relation
of 'remembered similarity', the form/content distinction does not coincide with
'designate nothing in and of themselves'". (1991, p. 227) Moreover, Carnap
the dichotomy between analytic and synthetic. (Friedman 1987, pp. 531-3)
claimed that "each object that is not one of my experiences is a quasi-object ...
6 7
traditional empiricist and Kantian accounts of the origins of scientific purely theoretical work in science. 5 By then describing a method of
concepts. The basic idea behind Schlick's treatment of implicit concept-formation that attains the twin goals of generality and precision,
definition was that scientific concepts are constituted by the network of he has denied any need for intuitions in scientific knowledge. It is thus
relations they bear to other concepts. To define concepts for a particular that he undermines the central notion of Kant's epistemology, pure
scientific field, one simply axiomatizes their relations to one another; the intuition, on which the doctrine of the synthetic a priori was founded.
resulting axiomatization, then, is just an implicit definition of the (Friedman 1983, p. 508) The result was a stark contrast between two
. concepts expressed by the terms occurring in the axioms. Instead of the distinct levels of cognitive activity. This dichotomy, expressed in
usual empiricist explanation of scientific concept-formation as an Schlick's General Theory of Knowledge as the difference between
abstraction from experience, or the traditional Kantian view of concepts concepts and intuition, would, in one guise or another, remain a central
derived from intuition, Schlick borrowed the notion of implicit definition feature of Schlick's thinking throughout his philosophical career. It
from Hilbert's work in geometry to argue that the system of scientific became especially prominent as the distinction between 'form' and
concepts is an autonomous network, consisting of elements that are 'content' in his philosophical writings in the late Twenties and early
simultaneously inter-defined. Thirties.
In the years 1926 to 1932 Schlick developed a comprehensive
The principle itself is amazingly simple. The task was to conception of language based on his earlier doctrine of implicit
introduce the basic concepts, which are in the usual sense definitions, suitably expanded and modified by means of notions
indefinable, in such a fashion that the validity of the axioms borrowed from Wittgenstein's Tracrarus. First he adapted Wittgenstein's
that treat of these concepts is strictly guaranteed. And doctrine of internal relations to the concepts of everyday discourse to
Hilbert's solution was simply to stipulate that the basic or show that these concepts are formally related in much the same way as
primitive concepts are to be defined just by the fact that they ones introduced by implicit definitions. Then the Tractarian account of
satisfy the axioms. (Schlick 1925, p. 33)
tautologies and contradictions was appropriated to establish that all the
meaning relations among expressions of a language are purely formal
Strictly speaking, a concept is said to be implicitly defined if it is a
and devoid of material content. The immediate result was a 'structural'
primitive introduced in an axiom-set. And ordinary nominal definitions,
or 'formal' conception of language, according to which the significance
which specify individually necessary and jointly sufficient conditions for
of any expression is founded on its logical relations to others. Not too
the application of the definiendum, are just a special case of implicit
surprisingly, Schlick thought the results gained from the structural
definitions. Thus introduced, scientific terms "acquire meaning only by
analysis of language could be readily applied in the theory of knowledge,
virtue of the axiom-system, and possess only the content it bestows on
them. They stand for entities whose whole being is to be bearers of the
relations laid down by the system." (1925, p. 34)
Schlick's critique of Kant rests on the rejection of general intuitions,
Of course, the reason Hilbert introduced implicit definition in the $
representations abstracted from all the objects falling under them. Schlick
first place was the same reason that Schlick used it in his discussion of
argued that it is simply impossible to conjure up an image, say, of a triangle
concepts: to display a method of concept-formation that guarantees
that is neither isosceles, nor scalene, nor equilateral. Rather, when we think
concepts are completely empty of intuitive content. In the context of
of an object in general --be it mankind or triangles or dogs-- what is present
geometry, Hilbert's goal was to assure a ground of absolute certainty for to our minds is a specific member of the general class that stands as a
geometric proofs; in the context of epistemology, Schlick's aim was to representative of the members of that class and, "linked with it, the
show how science develops abstract tools of sufficient generality and consciousness that the individual image is to count solely as a representative
adequate precision to account for scientific knowledge. It was here that of that class". ( 1925, p. 18) It is difficult to resist the criticism that Schlick' s
Schlick made his break with Kant. By showing that intuitions can never rejection of Kantian intuition conflates it with the purely psychological notion
be completely general or fully precise, he displayed their uselessness for of a mental image.
8
9
too.6
method. (1983, p. 309) Despite apparent differences in subject-matter,
In his 1930 essay "The Turning Point in Philosophy", Schlick
sciences as diverse as sociology and biology must rely on the same
proclaimed the beginning of a new era for the journal Erkenntnis, noting
epistemological means as physics. Thus there are no privileged modes
that the possibility of the philosophical outlook to be developed on its
of epistemological access for different domains of scientific
pages rested on the insight that "all knowledge is such only by virtue of
investigation. All assertions, from whatever field of inquiry, are
its form". (Schlick 1979b, p. 156) Of course, the contrast between form
verified by the methods of observation and experiment. These results
(or structure) and the content it informs was a familiar epistemological
were communicated to Carnap in conversations, and the stimulation they
theme in Positivist circles. And so appealing was the marriage of the
provided had immediate results on his own thinking. Carnap
structural analyses of language and knowledge, that its first offspring,
immediately endorsed both the thesis of Physicalism and that of the
the idea that "Only structure is knowable; only structure may be
Unity of Science, and incorporated them as leading themes in his own
expressed", was heralded in the pages of Erkenntnis as "the central
philosophy. Sometime around the middle of 1930, Carnap first began
thesis of the new epistemology" of the Logical Positivists. (Zilsel 1932-
to formulate the Physicalist conception of scientific knowledge, in the
33, p. 143) At about this time, news of the Vienna Circle was reaching
paper that would eventually be published as "Die physikalische Sprache
America, and in the Journal of Philosophy Herbert Feigl and Albert
als Universalsprache der Wissenschaft". After working on the essay for
Blumberg declared that the form-content distinction }s "one of the most
a half-year, he discovered the insight that would fundamentally alter the
important contributions of recent theory of knowledge." (Blumberg and
character of his thinking about philosophical topics, requiring a thorough
Feigl 1931, p. 287) Schlick's ultimate goal, then, was to show that any
overhaul of his essay. (Carnap 1963a, p. 52) This delayed the
possible cognition, any bit of information we might seek about the completion of his essay for about another year. 7 During this time,
world, can be communicated or expressed. Then the logical analysis of
Carnap formulated his insight as the Thesis of Metalogic: the contention
language would become the proper method of epistemology: to clarify
that, loosely speaking, all philosophical issues are metalinguistic,
meanings would be to illuminate the structure of a possible system of
concerning the nature of language and its logical structure. Applied to
knowledge! (Schlick 1979b, p. 156)
the problem of the basis, the Metalogic Thesis effectively transformed
During the same period, around the tum of the decade, Otto Neurath
the traditional issue into a question of the syntactic nature and
first articulated his ideas about Physicalism. At this stage, Physicalism
epistemological function of protocol sentences. It is at this point in the
was founded on the idea that statements belonging to every science
historical development of the Circle's thought that the story of protocols
referred only to physical events in space-time. (Neurath 1983, p. 54)
really begins.
This implies that all sciences are a unity in the sense that they share a
single language, that of physics. ( 1983, p. 52) This consequence, which
was already known as the Thesis of the Unity of Science, had been
2. Anticipations of Protocols
associated with the further contention that all sciences share a common
In the next chapter, the re-telling of the tale of protocols is begun
6 Schlick also thought atomic synthetic propositions possessed a 'material'
by describing the initial developments in the physicalistic account
structure in virtue of which they can say something, true or false, about the
world. (Schlick 1979b, pp. 287-93) This view of Schlick's has been taken as
evidence that he subscribed to all the details of the Tractatus' picture theory of
elementary proposition. It would be more accurate, however, to attribute 7 Thus, on January 16, 1932 Carnap wrote Neurath that he had completely
Schlick an endorsement of only the rudiments of Wittgenstein's theory,
re-written his manuscript of "Die physikalische Sprache ... ", on which he had
essentially those parts that explicate Frege's function-argument analysis of
been working for one and a half years. (Incidentally, he mentions that much
propositions.
of the progress on the paper was made during December of 1931, while Carl
Hempel was visiting him in Prague). (ASP, 029-12-70)
10 11
developed by C~a~ and Neurath. Working from the assumption that objective, cogni~ve gr~unds . .b ut must rest only on pragmatic
the results of scientific observation should be regarded as statements considerations of its relative utihty.
~hey were soon led to the conclusion that observations are not significan~ These developments lead to the episodes related in Chapter III,
m~ependent~y of theory, a point that has since been argued on strictly which are concerned with the reaction from the Circle's Right Wing,
e~istemological grounds. 8 But in Carnap's early writings on protocols, specially its leader Moritz Schlick. Schlick wholly rejected the
thi~ result was a consequence of the two leading precepts of his ;hysicalists' approach to protocols, for in his eyes it led inexorably
phtloso?hy, the principle of Physicalism and the Metalogic Thesis. towards a conception of truth as the coherence of the body of accepted
According to the latter precept, philosophical conceptions about the statements. Thus his essay "On the Foundations of Knowledge". began
nature . of observation are, properly expressed, opinions about the with a scathing critique of coherentism, and then developed his own
syntactic analysis of the statements describing observations. And conception of how protocols themselves are justified. S~hlick proposed
according to the thesis of Physicalism, all protocols, even first person to treat protocols as physicalistic statements that are mediately wa:ranted
reports of pe.rception, are meaningful only to the extent that they are by reports of immediate expe?ence .<"Konstatierungen"), whi~h ~e
translatable mto the physicalistic language of systematic science. themselves directly compared with reality. In response, the Physicalists
Consequently, Carnap argued that any objections to this conclusion were charged that Schlick's defense of the correspondence conception of truth
based on a failure to grasp the difference between the material and flew in the face of the leading tenets of their philosophy of language.
form~ mode~ of speech or, equivalently, a denial of the Metalogic For the notion of truth, conceived as correspondence, denied the Thesis
TheSIS on which the dichotomy was founded.
of Metalogic in attempting to go beyond the resources available in the
Neurath disparaged Carnap's conception of protocols as elements syntactic analysis of language. And the correspondence conception was
of a language separate from the physical language of systematic science, further thought to rely on a fundamentally metaphysical notion of the
and proposed to characterize protocols as physicalistic statements relationship between language and reality that was explicitly opposed to
describing t~e reports of observers. Neurath further argued that the conception of the Principle of Tolerance. And so the debate was on.
protoc~ls, hke all statements of physical science, are subject to Thus the history of the controversy recounted in Chapters II and
co~ection and hence fallible. In response, Carnap admitted Neurath's III shows that the issues arising in the discussion of protocols led
pomt that proto_cols are bes~ conceived as elP,ments of the physical directly to the underlying conceptions of language of the various
language of science, and hke all other scientific statements are disputants. Consequently, to understand the episten.10logi~al iss~es
corrigible. Nevertheless, Carnap himself endorsed the view of' Karl involved requires a thorough investigation of the respective philosophies
Popper, w~ich allowed that any scientific statement may, depending of language that founded the alternative approaches that figured in the
upon the cucumstances, be considered a protocol, in the sense that it debate. One central misconception that prevented not only the Vienna
represents at least a tentative stopping-point in the search for evidence Circle members but subsequent students of Positivism from appreciating
whi~h confirms or refutes the hypothesis under test. Then Carnap the logical issues in the controversy concerns the indubitability of
a~p~1ed another tenet of his philosophy of language to the question foundational statements. Throughout the protocol sentence controversy
an.sm~ among competing analyses of protocols. Thus, according to his it was presumed that, unless the statements at the base of the edifice of
Pnnciple of Tolerance, the selection of a particular treatment of knowledge were absolutely certain, they could not provide the evidential
protocols or, equivalently, the decision to adopt one 'protocol language' support required to say that the remaining statements of the structur~
rather than another, is conventional. It cannot itself be justified on were true in virtue of a correspondence with the facts. Conversely, 1t
was assumed that the fallibilism endorsed by the Physicalists, which
explicitly eschewed the doctrine of certainty, naturally imp~ied a
8 coherence account of truth. Yet it was not only the attraction of
By Paul Feyerabend, who likened the Physicalists' views on protocols to
•
fallibilism, or the rejection of the doctrine of certainty, that operated
hts own theory of observation in "Explanation, Reduction, and Empiricism".
(Feyerabend 1981, p. 49) But more on this in Chapter II. against the concept of truth in the Physicalist p~ilo~p?y. . R~ther,
according to the argument of Chapter IV, the Phys1cal1sts reJectlon of
13
12
the correspondence conception of truth was actually founded on the Circle's earlier days, sort of an empiricist construal of the Tractatus'
theory of meaning. In opposition to this widespread opinion, it is
deepest philosophical considerations underlying Carnap's Logical Syntax
of Language. Indeed, the whole syntacticist program, as conceived by argued in Chapter V that, at the time of the ~rotocol sentence
Carnap, was anathema to the correspondence conception of truth. controversy, Moritz Schlick endorsed a conception of language
In the light of the account given in Chapter IV, the original surprisingly like Carnap's. Thus, where the Physicalists (and subsequent
motivation for Carnap's development of his Syntax philosophy was commentators) have seen a fundamental divergence in the philosophies
provided by a central, unsettled problem in the understanding of of language of the opposing factions, there were significant areas of
language associated with the logicist philosophy of mathematics. This agreement. Indeed, Schlick's endorsement ~f correspond.ence was the
problem required a solution compatible with recent results in logic, to centerpiece of a conception of language which, tho~g~ it shared key
preserve the core of the theory of meaning implicit in the work of earlier precepts of Carnap's Syntax views, depart~ from. i~ m fundamental
logicists, particularly Frege and Wittgenstein. Carnap's solution respects. Thus it will be argued that Schhck exphcitly endor~ the
consisted of his development of logical syntax to provide the means for conventionalist theme of Carnap's Principle of Tolerance, as testified by
expressing metalinguistic discourse in the object-language. As such, the his essays and lectures at the time of the protocol sentence contro~ersy.
solution Carnap discovered required a strictly syntactical analysis of And it will be further contended that his approach to the analysis and
language, one which divided meaningful statements into object-language dissolution of pseudo-problems was guided by a metalinguistic
(or 'real-object') sentences dealing strictly with extra-linguistic things, conception of philosophy like the one emb~i~ in Carnap's 1:hesis of
and metalinguistic (or 'syntactical') statements referring only to linguistic Metalogic. Significantly, Schlick's characten~tion of l~guage mcl~ded
expressions and their logically specifiable properties. This bifurcation logical rules never countenanced by Carnap s syntactic conceptions.
provided the grounds for Carnap's further contrast between the formal These rules go beyond syntactical ones, fo~ the~ are c~ncer:n~
and material modes of speech. The former category includes only exclusively with the application of expressions in non-linguistic
syntactical, metalinguistic statements, while the latter captures statements environments. And it was on the basis of Schlick's account of these so
which, by their phrasing, appear to be real-object sentences but which called 'application rules' that he founded his arguments for the
are revealed, by logical analysis, to be syntactical sentences. Carnap intelligibility of the correspondence conception of truth. Yet'. as ar~ued
also called these material mode statements 'pseudo-object sentences' and at the end of Chapter V, Schlick's arguments contain senous
argued that philosophical pseudo-theses, the claims at the center of shortcomings that raise questions about the very possibility of vindicating
fruitless philosophical controversies, are one and all pseudo-object his conception of truth.
sentences of the material mode of speech. Prominent among these are In the final installment, Chapter VI, the inquiry returns to
statements that purport to analyze language in terms of the relations Carnap's Logical Syntax, with the goal of showing that the syn~cticist
borne by expressions to non-linguistic things, including statements about enterprise of the book is internally flawed. Th~ first rea~on is that
the truth and falsehood of other statements. And some of the most Carnap's definition of analyticity for Lan~uage II is, f~r all intents and
troubling passages in the Logical Syntax are those where Carnap argued purposes, a definition of truth for th~ logico-mathematical fragment ?f
that the notions 'true' and 'false' must be excluded from the analysis of the language. This is shown by tracing the analogy borne by Carnap s
language because they are not proper syntactical concepts. Examining treatment of 'analytic in II' to Tarski's semantic definition of ~th. In
these arguments leads to the conclusion that the correspondence notion this context it is argued that Carnap's definition is essentially a
of truth violates the most fundamental philosophical insights of Carnap's substitutional explication of truth, differing from Tarski's semantical
Logical Syntax philosophy of language. conception only notationally. Yet, in C~ap's con~ption, these
Nor would it be correct to conclude, from the force of Carnap's notational deviations bear the burden of the entire syntactic1st program.
syntactic arguments against truth, that the alternative conception of Here the inherent weaknesses in Carnap's constructions are most
Moritz Schlick was either fallacious or founded on false premises. obvious. And these weaknesses might, in themselves, be tolerable were
Nonetheless, it is widely thought that Schlick and the rest of the Right it not for the fact that the final infirmity of the Syntax uncovered in this
Wing clung to an outmoded view of language characteristic of the investigation afflicts its very heart and soul.
