Title: Compositionality in Transparent Intensional Logic
1Compositionality in Transparent Intensional Logic
- Pavel Materna
- Institute of Philosophy,
- Academy of Sciences of Czech Republic
- Prague
- materna_at_lorien.site.cas.cz
2Compositionality Definitions
- Compositionality is a condition. It is
- a condition on semantics for languages. A
common statement of it is that the meaning of a
complex expression is a function of the meanings
of its immediate constituents and the
grammatical rule which is used to combine them - (Hodges 2001, 7)
- In other words, the meaning of a complex
expression - is determined by the meanings of the component
expressions plus the way they are combined into
the complex expression. - (Sandu, Hintikka 2001, 49)
3Formal definition of compositionality
- Consider now F, a k-ary syntactic operation on
E. m is F-compositional just in case there is a
k-ary partial function G on M such that whenever
F(e1,,ek) is defined, then - m(F(e1,,ek)) G(m(e1),,m(ek)).
- (Szabó 2005, 5)
- E set of expressions, m a meaning-assignment,
- M set of available meanings
- (Cf. also Stechow, Wunderlich 1991, 107.)
4Two problems
- A.
- In which way does the syntactic function F break
the given expression into (immediate)
constituents (component expressions)? - B.
- What do we mean by meaning?
5Component expressions syntactic task?
- Autonomous syntax
- It would bein vain to ask an autonomous
syntactician what the term constituent means.
He certainly cannot say that a constituent is an
expression which is complete in that it refers
all by itself to a definite entity, in contrast
to an incomplete expression which refers only in
combination with some other expressions. For
that would amount to leaving the domain of
autonomous syntax. The term constituent (or
phrase) is apparently not to be burdened with
any pre-theoretical meaning at all a constituent
is simply whatever the grammarians theory brands
as such in any particular case. - (Tichý 2004, 807)
- logical grammar, with its principle of
compositionality of meaning, goes straight
against the autonomy of syntax so cherished in
the generative tradition. And that means, at
least in principle, that semantic considerations
may influence the syntax, thus breaching the
supposed autonomy of syntax. - (Gamut 1991, 141)
6Compositionality logical languages vs. natural
language
- The principle of compositionality of meaning has
important consequences for the relationship
between syntax and semantics. Usually in a
logical system the definition of the semantic
interpretation of expressions closely follows the
lead of their syntactic construction. The
obvious way to proceed is to let the definition
of the semantics parallel the finite, recursive
definition of the syntax. Succinctly put, logical
languages satisfy the following principle the
interpretation of a complex expression is a
function of the interpretations of its parts.
every syntactic rule should have a semantic
interpretation and on the other hand, every
aspect of the semantics which is not related to
the interpretation of basic expressions should be
linked to a syntactic operation. - But a natural language is not something we
construct it comes as given. (Gamut
1991, 140) - Thus it seems that the Tarskian semantics of
formal languages has got compositionality gratis.
Whatever can be called meaning in such
languages is stipulated in such a way that the
syntactic rules (determining, e.g., which
concatenation of symbols counts as well-formed
formula) select just those components of an
expression that get due to the interpretation
unambiguously a meaning, and derive
unambiguously the meaning of the whole
expression from the meanings of the components.
7Two consequences of compositionality
- Two simple consequences of compositionality are
- a compositional semantics is Husserlian (see
below), - synonyms are substitutable
- Ad i) The term Husserlian has been introduced
by Hodges in his (2001). Roughly, a semantics S
is Husserlian if for every expressions E, E it
holds that if E is synonymous with E in S then E
belongs in S to the same (Tarskian) category as
E i.e., the expression containing E as its
subexpression is S-meaningful just if the
expression containing E in the place of E is
S-meaningful. - Ad ii) If E is synonymous with E in S then so
is any expression A containing E as its
subexpression with the expression B that arises
from A by substituting E for E
8Natural language ambiguities
- Simple examples show that both i) and ii) cannot
be satisfied if applied to expressions of a
natural language. The reason is that natural
languages, which come as given, are replenished
by ambiguities. - One kind of ambiguities comprises lexical
ambiguities. These are rather simple and can be
thought of as corrigible. They make it
impossible to satisfy even the Husserlian
condition. For example, consider the word means.
To be Husserlian the semantics would have to
admit that since What Charles means is that is
meaningful and we can (roughly) claim that means
and resources are synonymous then What Charles
resources is that were likewise meaningful.
9Natural language non-lexical ambiguities
- The non-lexical ambiguities are especially
insidious. Here is an example of a sentence that
seems not to contain any lexical ambiguity but
does not admit an unambiguous interpretation
(cf. also the famous Montagues example with
seeking unicorns) - Charles wants to marry a princess.
- An expression may be ambiguous without having
two distinct constituent structures. But
compositionality simply requires that there be
different parts whenever there is non-lexical
ambiguity, and if none of the known notions will
do, the parts have to be invented.
compositionality demands a disambiguated level of
representation in the syntax. (Gamut 1991,
218)
10Logical analysis of natural language
- Summarising
- Identifying the component expressions of a
complex NL expression presupposes a logical
analysis of the natural language (LANL). This is
because of the fact that natural expressions
develop spontaneously so that the logical
structure underlying the natural encoding given
by the language (NB at the given stage of its
development) remains hidden and has to be
discovered. The degree of the adequateness of
such discovery should be dependent on the degree
in which the respective LANL could ensure that
compositionality holds. - As for the disambiguation necessary according to
the above quotation, LANL should be capable to
offer to each reading (i.e., to each analysis
tree) of an ambiguous expression a separate
logical construction (indeed, under the
assumption that the component expressions
occurring in the tree have been determined as
meaningful expressions and the dependencies
between the particular terminals are mediated via
rules admitting semantic interpretation).
11Horwich compositionality independent of the
definition of meaning?
- No great problems with compositionality are
admitted from a deflationary viewpoint. Horwich
formulates the problem as follows - The issue of how the meanings of sentences are
built out of the meanings of their constituents
words - (Horwich 1997, 503)
- Further he claims that
- the compositionality of meaning imposes no
constraint at all on how the meaning properties
of words are constituted. (Ibidem) - If this Horwichs claim means that
compositionality holds independently on how the
notion meaning is defined then it can be easily
demonstrated that this claim is wrong.
12Reference, denotation, meaning I TIL
- The main principles of TIL can be found in the
work of the founder of TIL Pavel Tichý (see his
Collected papers (2004), and his monograph
(1988)) further information is offered, e.g., by
Materna, P., Duží, M. (2005) and the important
definitions in Duží, M., Materna, P. (2005).
Since the apparatus is available in the
literature just mentioned I will try to get along
without formal definitions, and since the
principles have been sufficiently defended in
that literature I will only mention them and show
how they help to elucidate the problems of
compositionality. - Let us return to various definitions of
compositionality. In all of them what is said to
be a function of or determined by is called
meaning. We can therefore ask what sort of stuff
meaning is (Horwich) or simply state that
meaning is in such definitions a generic rather
than specific term (Sandu, Hintikka). In the
latter text the authors propose to speak of the
different semantic attributes of an expression.
Now we will examine three such semantic
attributes and show that only one of them can
guarantee such a disambiguation of a natural
language which makes it possible to let
compositionality hold.
13Reference, denotation, meaning II Freges sense
- Tichýs criticism of Freges semantic schema
- a) Sense
- Frege has characterized his sense as a mode of
presentation of the object denoted (die Art des
Gegebenseins), which is, of course, no
definition. No wonder that, e. g., Bertrand
Russell refused to accept such an indefinite
notion. In any case, the lack of a satisfactory
definition led to never ending discussions
concerning necessity and character of sense, or,
as we use to say nowadays, meaning.
Alternatively, meaning is conceived of as having
at least two components the sense and the
reference (Kirkham 1992/1997, 4). - Since the term sense is no more frequently used
we will use the term meaning as one of the levels
that are connected with semantics and let it play
the role that corresponds to Freges
characterization of sense as a mode of
presentation.
14Reference, denotation, meaning III Freges
denotation
- b) Denotation
- If the object denoted were unambiguously
determined by the sense then Freges notion of
denotation (Bedeutung) as illustrated by his
famous example with morning star vs. evening star
does not satisfy this requirement. - For Frege the expression morning star as well as
evening star denotes Venus, the particular
celestial body. Imagine however a well thinkable
(in any case possible) situation when the role
played by the morning star (being the brightest
celestial body in the morning sky and suchlike)
begins to be played by another body, say, Mars. A
natural way to state this change is to say Now
Mars became the morning star. The sense be it
anything connected with the term morning star
did not change but the Fregean denotation did.
This is a consequence of what Tichý calls e.
g., in (2004, 825) - Freges Thesis, viz. that an expression is
not a name of the determiner itself but rather of
the object, if any, determined by it.
15Reference, denotation, meaning IV Criticism
of Freges Thesis
- The relation of denoting, if conceived of as a
semantic relation (as it should be, at least if
semantics of NL is construed as LANL), is, of
course, a necessary relation. - Thus what is denoted by an empirical expression
is always just a condition to be fulfilled by an
object of the given type. Such conditions (called
determiners in the above quotation) are best
modeled as intensions in the sense of P(ossible)
W(orld) S(emantics). Intensions are in this sense
functions mapping possible worlds to objects of
the given type, mostly to chronologies of such
objects, i.e., to functions from time moments. - Objects that are not intensions are extensions.
- Empirical expressions denote intensions due to a
linguistic convention (which is given and which,
therefore, enables us to say that from the
viewpoint of LANL the denotation of an empirical
expression is given a priori). - Now whereas empirical expressions denote
intensions independently of their instantaneous
actual population and are so immune to
empirical facts (so that the relation of denoting
is necessary) we can consider the value of any
such intension in the actual world-time. This is
our opportunity to distinguish - denoting as a necessary, independent of empirical
facts relation, and referring (or reference) as a
contingent relation that is irrelevant as being
contingent for LANL.
16Reference, denotation, meaning Examples
- the capital city of Poland denotes the
intension called individual role (Church has
called it individual concept), which returns as
its value in W at T at most one individual its
reference in the actual world-time is Warsaw, the
town - The capital city of Poland is Warsaw denotes
the proposition (a function from possible worlds
to chronologies of truth values) its reference
in the actual world-time is the truth-value True - star denotes a property its reference in the
actual world-time is the set of all actual stars
- etc. etc.
17Actual world. Non-empirical expressions
- One misunderstanding should be avoided we can
speak about the actual world but logically it is
inaccessible. Saying, e.g., I am actually
hungry we do not say anything more than I am
hungry. A systematic explanation of this
frequently ignored fact can be found in Jespersen
(2005). - As for the non-empirical, in particular
mathematical expressions, to distinguish between
denotation and reference is inoperative - semantics of mathematical expressions does not
need any possible worlds or times, and - non-empirical (analytic) expressions containing
empirical subexpressions denote constant
intensions, i.e., functions whose value in all
worlds-times is the same.
18Sense is not an intension
- A frequent interpretation of Freges sense in the
post-Fregean literature consists in construing it
as intension - At least two essential objections to this
identification of senses with intensions are - Let the sense of an (empirical) expression be the
intension of the given type. Then the only object
that would correspond to the denotation could be
the value of the intension in the actual world.
Then the link between the sense defined in this
way and the denotation would be contingent, not
unambiguous. For example, if the sense of the
sentence There are exoplanets where there live
mammals were its truth-condition, i.e., the
respective proposition, then what would be
denoted would be a truth-value. But the
proposition itself does not possess the force of
determining the truth-value. We need empirical
methods to verify/falsify empirical sentences. - Mathematical expressions would not possess any
sense, since they are independent of intensions.
19Meaning (sense) as an abstract procedure
- Let us consider some mathematical expression,
say, - 3 2 ? 0.
- The most natural answer to the question what this
expression denotes is probably that it is the
truth-value True. What would be the way that
links the expression with this truth-value,
playing thus the role of the Fregean sense? - The general form of the answer has been given by
Tichý as early as in (1968) and (1969). The
Fregean sense is best construed as an abstract
procedure. Later during developing the system
of TIL Tichý has formulated exact definitions
of such procedures they are what is called in
TIL constructions and formally are influenced by
the ingenious Churchs idea that two
operations/procedures are the core of handling
functions creating functions via abstraction and
applying functions to arguments, which led to
?-calculi. What the typed ?-calculus formulates
on the level of formal languages TIL interprets
objectually
20Constructions I.
- Variables, compositions (?-applications),
closures (?-abstractions), trivializations (0X
constructs X without any change) and double
executions (where C is a construction that
constructs a construction D the double execution
2C constructs what constructs D) are
extra-linguistic procedures, and the language of
constructions is no formal language in the
standard sense but only a direct code that
enables us to deal with the abstract procedures. - Writing X X1Xm for applying what is
constructed (maybe dependently on valuations v)
by X to what is constructed by X1,,Xm, and
?x1xm X for constructing a function
(technically just as it is done in ?-calculus)
we can logically handle procedures working in
the area of (partial) functions over some simple
types and even in the area of constructions
themselves, which get their types and become thus
a kind of objects to be mentioned (not only used)
within a ramified hierarchy of types.
21Constructions II.
- Constructions as abstract procedures embody an
important property which a meaning of an
expression should possess they are
(algorithmically) structured. Tichýs and
Cresswells (see his (1985) ) idea of structured
meanings (see also the more recent Moschovakis
(1994)) has been realized in TIL in a systematic
way - meaning of an expression is a construction, and
LANL tries to find such a construction that would
obey compositionality. (See Materna, Duží
(2005).) - A special kind of construction can be defined
roughly, a closed construction, i.e., a
construction not involving free variables. Such
a construction has been called concept (see
Materna (1998, 2004)). - The meaning of any non-indexical expression is
accordingly a concept.
22Denotation, reference, meaning
- Summarising
- Fregean levels (sense, denotation/reference) have
been revised in TIL as follows - i) Empirical expressions of a natural language
denote intensions, never their values in the
actual world-time. - ii) Reference, as the value of the denotation in
the actual world-time, is logically (and thus for
LANL) inaccessible, hence it cannot be dealt with
within LANL. - iii) Meaning of an expression E is a
construction if E is a non-indexical expression
its meaning is a concept. Meaning in this sense
constructs what the expression denotes, which is
as it should be.
23Constructions Example I.
- Returning to our example we can write down the
concept that is the meaning of this mathematical
sentence (whose denotation is True) - 0? 0 03 02 00
- i.e. the function ? constructed by
trivialization is applied to the pair M, N of
procedures, where M is application of the
subtraction function (constructed by
trivialization) to the pair of numbers 3, 2
(constructed by trivialization) and N is
trivialization of 0.
24Constructions Example II.
- To show an example of an empirical sentence let
us consider the sentence - Charles believes that the Moon is bigger than the
Earth. - Reading Charles has the property of believing
that the Moon is bigger than the Earth. - Charles, Moon and Earth ? names of definite
individuals (a simplification, of course), - bigger than ? name of a binary
relation-in-intension between individuals, - believe that ? a relation-in-intension between
an individual and a proposition. - w is a variable ranging over the type of possible
worlds, - t ranges over the type of time moments ( real
numbers), - x ranges over the type of individuals.
- Abbreviating Xwt as Xwt and omitting brackets
where there is no danger of confusion we analyze
our sentence as follows - ?w?t ?w?t ?x 0Belwt x ?w?t 0Biggerwt 0Moon
0Earthwt 0Charles
25Compositionality w.r.t. reference, denotation
and meaning I.
- Once more, let compositionality be defined like
in Szabó - m(F(e1,,ek)) G(m(e1),,m(ek)).
- We will try to examine what happens if m is
interpreted as - a) reference, b) denotation, c) meaning (defined
as above) - Let us recollect that synonymy is defined as
follows - The expression E is synonymous with the
expression E iff - m(E) m(E).
- Finally, an easily derivable consequence of
compositionality is - If e is a constituent of E, and if E is like E
with the only distinction that e is replaced by
e, then - m(e) m(e) implies m(E) m(E).
- (Principle of substitutability, PS)
26Compositionality w.r.t. reference, denotation and
meaning II a) m is reference
- Obviously, if reference is defined as above then
we cannot expect that the m in definition of
compositionality were reference. Indeed, we can
easily prove that the PS does not hold for
reference. - Let our Charles believe that the following
sentence is true - The Moon is bigger than the Earth.
- Now the truth-value of the proposition denoted by
this sentence in the actual world-time? and so
the reference of the sentence ? is False. Hence
the sentence is synonymous (w.r.t. reference)
with the sentence - Every woman has two wings.
- If PS held for reference Charles would have to
believe that this sentence too were true. But he
does not have to, of course. - In the semantics for which the meaning of E
equals the reference of E the PS does not hold so
that compositionality does not hold either.
27Compositionality w.r.t. reference, denotation and
meaning III b) m is denotation.
- We can immediately show that in this case
doxastic or epistemic contexts make PS fail.
Indeed, consider the sentences - A. Some dogs are dangerous.
- B. Some dogs are dangerous and the only even
prime is two. - The sentence A. is synonymous with the sentence
B. w.r.t. denotation The point is that the
proposition denoted by The only even prime is
two is true in all worlds-times. Thus the
conjunction of the sentence A. with the sentence
B. denotes one and the same proposition. If PS
held for m denotation then the following two
sentences would be synonymous - Charles believes that some dogs are dangerous.
- Charles believes that some dogs are dangerous
and (that) the only even prime is two. - This is however evidently not the case.
- In the semantics for which the meaning of E
equals the denotation of E PS does not hold so
that compositionality does not hold either.
28Compositionality w.r.t. reference, denotation and
meaning IV c) m is a concept
- First of all, this case is immune to
counterexamples like those ones that were adduced
in a) or b). - For example, the sentences A. and B. above are
not synonymous w.r.t. meaning the construction
(concept) underlying A. differs from the
construction (concept) underlying B. - This does not mean, however, that other
counterexamples cannot be found. Consider the
following ones - 0yellowness constructs the same property as
0yellow. - (Properly speaking, these are two ways of
encoding in TIL one and the same construction.) - Yet we cannot say This house is yellowness
it seems that our semantics is not even
Husserlian! - Solution The distinction between yellowness and
yellow is in fact no distinction of meaning. Yet
a distinction is present the ness in the first
expression signalizes that this name of a
property can be used only if the property is
mentioned (i.e., is in the supposition de dicto)
rather than used to be predicated of something.
(Thus there is a constraint to compositionality,
which could be classified as compositionality in
the sense iii) in Sandu, Hintikka (2001, 50).)
There are more such signals in natural languages,
cf. bravery vs. brave, in German Tugend vs.
tugendhaft, schön vs. Schönheit etc. As soon as
such a signal occurs in the respective analysis
tree compositionality is no more jeopardized in
this respect.
29Compositionality w.r.t. reference, denotation and
meaning IV c) m is a concept
- ii) Without any lexical change the sentence
Charles wants to marry a princess. allows for two
readings - a) There is a princess and Charles wants to
marry he - b) Charles wants that there were a princess whom
he would marry. - So the expression to want to marry a princess
as if denoted two properties. - Indeed, let Charles have the property according
the reading a). - Peter might have the property according to
reading b). - A simple substitution of the expression wants to
marry a princess into both the statements that
claim the possessing of a property by Charles and
Peter would not result in the claim that Peter
has the same property as Charles. - Solution The possible readings a) and b) show
that - 1. disambiguation is possible,
- 2. the ambiguous sentence is something like an
abbreviation (where semantic distinctions are
lost). There are two meanings (concepts)
belonging to the sentence, each of them is the
meaning of one of the two readings. (See
Appendix.) - No problem with compositionality arises after the
disambiguation has been realized.
30Compositionality w.r.t. reference, denotation and
meaning V c) m is a concept
- iii) Suppose that Charles seeks the murderer of
his father. - Analyzing simple words as expressing
trivialized objects (simple concepts, Materna
(2004)) can we really say that in any context
0seek is sufficient? - Consider the situation when Charles says
Success, it is Peter X! and another situation
when he says Success, he was in his flat! - Solution This is again a problem of
disambiguation. - In a disambiguated language we would have
- seek1 as look for the place where X occursand
- seek2 as investigate who plays the role of or
so. - The resulting ambiguity is, as a matter of fact,
a lexical ambiguity and should be signalized in
the linguistic resources on which the analysis
trees are based.
31Appendix
- We will show the two meanings that correspond to
the two readings of the sentence - Charles wants to marry a princess.
- Simple types atomic ? True, False
- ? individuals
- ? time moments / real numbers
- ? possible worlds (logical space)
- functional (??1?m)
partial functions from ?1 ? ? ?m to ? - Types of objects Charles ?
- Want (((??((??)?)?)?)?) abbr. (? ?
(??)??)?? - (relates an individual X with a property, viz.
which X wants to possess) - Marry (???)??
- Princess (??)?? in general ???
abbreviates ((??)?) - Types of logical functions ? (???)
- ?
(?(??)) - Variables w ? ?, t ? ?, x, y ? ?
- First reading There is a princess and Charles
wants to marry her. - ?w?t 0??x 0? 0Princesswt x 0Wantwt0Charles
?w?t ?y0Marrywty x - Second reading Charles wants that there were a
princess and he would marry her. - ?w?t 0Wantwt0Charles ?w?t?y 0? ?x 0?
0Princesswt x 0Marrywty x
32References I.
- Cresswell, M.J. (1985) Structured Meanings, MIT
Press, Mass. - Duží, M., Materna, P. (2005) Logical Form. In
Sica, G., ed. Essays on the Foundations Of
Mathematics and Logic, Polimetrica International
Scientific Publisher Monza/Italy - Gamut, L.T.F. (1991) Logic, Language and Meaning
II., Intensional Logic and Logical Grammar.
Chicago University Press. - Hodges, W. (2001) Formal Features of
Compositionality. Journal of Logic, Language,
and Information 10, 7-28 - Horwich, P. (1997) The Composition of
Meanings, The Philosophical Review, Vol 106 No
4, 503-532 - Jespersen, B. (2005) Explicit
Intensionalization, Anti-Actualism, and How
Smiths Murderer Might Not Have Murdered Smith
Dialectica 59/3, 285-314 - Kirkham, Richard L. (1992/1997) Theories of
Truth. The MIT Press, Cambridge, Mass., London
1992, 4th printing 1997. - Materna, P. (1998) Concepts and Objects. Acta
Philosophica Fennica 63, Helsinki
33References II.
- Materna, P. (2004) Conceptual Systems. Logos
Verlag, Berlin - Materna, P., Duží, M. (2005) Parmenides
Principle (The analysis of aboutness)
Philosophia 32, Nos 1-4, 155-180 - Moschovakis, Y. N.(1994) Sense and denotation as
algorithm and value, Postscript file, 39 pages
Published in Lecture Notes in Logic, 2 (1994),
Springer J. Oikkonen and J. Vaananen, eds. pages
210-249. - Sandu, G., Hintikka, J. (2001) Aspects of
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Stanford Encyclopedia of Philosophy
lthttp//plato.stanford.edu/archives/spr2005/entrie
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Prague University of Otago Press, Dunedin
34Appendix II.
- Let us return to the sentence Charles believes
that the Moon is bigger than the Earth. - In any analysis tree the following components
(constituents) will occur - a) Charles believes that the Moon is bigger
than the Earth. .t - b) Charles..t1
- c) believe..... t21
- d) the Moon.t221
- e) (is) bigger than..t222
- f) the Earth.t223
- g) that the Moon is bigger than the
Eartht22 - h) believe that the Moon is bigger than the
Eartht2 - A probable structure of the respective analysis
tree can be suggested as follows - a) t(t1, t2(t21, t22 (t221, t222,
t223))) - We can see that the particular steps
(subconstructions, subconcepts) of the meaning of
the sentence correspond to the constituents of
the suggested tree above and that the syntactic
dependencies that make up this tree correspond to
the objectual functions constructed by the
particular subconstructions. - ?w ?t ?w ?t ?x 0Belwt x
?w ?t 0Biggerwt 0Moon 0Earthwt
0Charles - C3(e) t222 C4(d) t221
C5(f) t223 -
- C1(c)t21 C6(g) t22
-
C8(h) t2 C2(b) t1