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All the ideas for 'Structures and Structuralism in Phil of Maths', 'Leibniz' and 'Truth and Predication'

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51 ideas

3. Truth / A. Truth Problems / 2. Defining Truth
A comprehensive theory of truth probably includes a theory of predication [Davidson]
     Full Idea: Theories of truth and theories of predication are closely related: it seems probable that any comprehensive theory of truth will include a theory of predication.
     From: Donald Davidson (Truth and Predication [2005], 6)
     A reaction: Davidson defends the view that it is this way round. It is tempting to label them both as 'primitive'. Davidson distinguishes a 'theory' about truth from a 'definition'.
3. Truth / A. Truth Problems / 3. Value of Truth
Antirealism about truth prevents its use as an intersubjective standard [Davidson]
     Full Idea: Antirealism, with its limitations of truth to what can be ascertained, deprives truth of its role as an intersubjective standard.
     From: Donald Davidson (Truth and Predication [2005], 2)
     A reaction: I like this, because it lifts truth out of individual minds. I take truth to be an ideal - a simple one with little content, which is thus fairly uncontroversial. Truth is the main general purpose of thinking.
3. Truth / A. Truth Problems / 8. Subjective Truth
'Epistemic' truth depends what rational creatures can verify [Davidson]
     Full Idea: The 'epistemic' view of truth asserts an essential tie to epistemology, and introduces a dependence of truth on what can somehow be verified by finite rational creatures.
     From: Donald Davidson (Truth and Predication [2005], 2)
     A reaction: This view, which seems to be widely held, strikes me as an elementary confusion. I take truth to be fully successful belief. If you say belief can never be fully successful, then we can't know the truth - but that doesn't destroy the concept of truth.
3. Truth / C. Correspondence Truth / 3. Correspondence Truth critique
There is nothing interesting or instructive for truths to correspond to [Davidson]
     Full Idea: The real objection to the correspondence theory of truth is that there is nothing interesting or instructive to which true sentences correspond. (C.I. Lewis challenged defenders to locate the fact or part of reality to which a truth corresponded).
     From: Donald Davidson (Truth and Predication [2005], 2)
     A reaction: Davidson defended a correspondence view in 'True to the Facts'. Davidson evidently also thinks the same objection applies to claims about truthmakers. If you say 'gold is shiny', the gold is very dispersed, but it is still there.
The Slingshot assumes substitutions give logical equivalence, and thus identical correspondence [Davidson]
     Full Idea: The Slingshot argument (of Frege, Church and Gödel) assumes that if two sentences are logically equivalent, they correspond to the same thing, and what a sentence corresponds to is not changed if a singular term is replaced by a coreferring term.
     From: Donald Davidson (Truth and Predication [2005], 6)
     A reaction: This obviously won't work for 'Oedipus thinks he ought to marry Jocasta'. Sentences correspond, I presume, to what they are about, which is often a matter of emphasis or phrasing. Hence the Slingshot sounds like nonsense to me.
Two sentences can be rephrased by equivalent substitutions to correspond to the same thing [Davidson]
     Full Idea: Slingshot: 'Scott is the author of Waverley' and 'The number of counties in Utah is twenty-nine' can be rephrased by substitution so that they are both about the number twenty-nine, and are thus correspond to the same thing.
     From: Donald Davidson (Truth and Predication [2005], 6)
     A reaction: [my paraphrase of Davidson's quote from Church 1956:24] These sentences clearly do not correspond to the same thing, so something has gone wrong with the idea that logically equivalent sentences have identical correspondents.
3. Truth / D. Coherence Truth / 1. Coherence Truth
Coherence truth says a consistent set of sentences is true - which ties truth to belief [Davidson]
     Full Idea: A pure coherence theory of truth says that all sentences in a consistent set of sentences are true. ...I class this with epistemic views, because it ties truth directly to what is believed.
     From: Donald Davidson (Truth and Predication [2005], 2)
     A reaction: [He cites Neurath] I would have thought that coherence is rather more than mere consistency. Truths which have nothing whatever in common can be consistent with one another. [but see his p.43 n14]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / b. Satisfaction and truth
We can explain truth in terms of satisfaction - but also explain satisfaction in terms of truth [Davidson]
     Full Idea: Truth is easily defined in terms of satisfaction (as Tarski showed), but, alternatively, satisfaction can be taken to be whatever relation yields a correct account of truth.
     From: Donald Davidson (Truth and Predication [2005], 2)
     A reaction: Davidson is assessing which is the prior 'primitive' concept, and he votes for truth. A perennial problem in philosophy, and very hard to find reasons for a preference. The axiomatic approach grows from taking truth as primitive. Axioms for satisfaction?
Satisfaction is a sort of reference, so maybe we can define truth in terms of reference? [Davidson]
     Full Idea: That the truth of sentences is defined by appeal to the semantic properties of words suggests that, if we could give an account of the semantic properties of words (essentially, of reference or satisfaction), we would understand the concept of truth.
     From: Donald Davidson (Truth and Predication [2005], 2)
     A reaction: If you thought that words were prior to sentences, this might be the route to go. Davidson gives priority to sentences, and so prefers to work from the other end, which treats truth as primitive, and then defines reference and meaning.
Axioms spell out sentence satisfaction. With no free variables, all sequences satisfy the truths [Davidson]
     Full Idea: Axioms specify how each unstructured predicate is satisfied by a particular sequence. Then recursive axioms characterise complex sentences built from simpler ones. Closed sentences have no free variables, so true sentences are satisfied by all sequences.
     From: Donald Davidson (Truth and Predication [2005], 7)
     A reaction: I take 'all sequences' to mean all combinations of objects in the domain. Thus nothing in domain contradicts the satisfied sentences. Hence Tarski's truth is said to be 'true in a model', where the whole system vouches for the sentence.
3. Truth / F. Semantic Truth / 2. Semantic Truth
Many say that Tarski's definitions fail to connect truth to meaning [Davidson]
     Full Idea: It is complained that Tarski's definitions do not establish the connection between truth and meaning that many philosophers hold to be essential.
     From: Donald Davidson (Truth and Predication [2005], 1)
     A reaction: This, of course, was Davidson's big mission - to build on Tarski's theory a view of truth which dovetailed it with theories of meaning and reference.
Tarski does not tell us what his various truth predicates have in common [Davidson]
     Full Idea: There is no indication in Tarski's formal work of what it is that his various truth predicates have in common, and this is part of the content of the concept.
     From: Donald Davidson (Truth and Predication [2005], 1)
     A reaction: This seems like a good question to raise. If I list all the 'red' things, I can still ask what qualifies them to all appear on the same list.
Truth is the basic concept, because Convention-T is agreed to fix the truths of a language [Davidson]
     Full Idea: The key role of Convention-T in determining that truth, as characterised by the theory, has the same extension as the intuitive concept of truth makes it seem that it is truth rather than reference that is the basic primitive.
     From: Donald Davidson (Truth and Predication [2005], 2)
     A reaction: The key strength of Tarski's account is that it specifies the extension of 'true' for a given language (as expressed in a richer meta-language).
To define a class of true sentences is to stipulate a possible language [Davidson]
     Full Idea: When we enquire whether a truth definition defines the class of true sentences in a particular language, we are thinking of the truth definition as stipulating a possible language.
     From: Donald Davidson (Truth and Predication [2005], 7)
     A reaction: Thus I might say "Nij wonk yang" is true if and only if snow is white, and make my first step towards a new language. An interesting way of looking at Tarski's project.
While true-in-a-model seems relative, true-in-all-models seems not to be [Reck/Price]
     Full Idea: While truth can be defined in a relative way, as truth in one particular model, a non-relative notion of truth is implied, as truth in all models.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §4)
     A reaction: [The article is actually discussing arithmetic] This idea strikes me as extremely important. True-in-all-models is usually taken to be tautological, but it does seem to give a more universal notion of truth. See semantic truth, Tarski, Davidson etc etc.
3. Truth / H. Deflationary Truth / 1. Redundant Truth
Truth is basic and clear, so don't try to replace it with something simpler [Davidson]
     Full Idea: Truth is one of the clearest and most basic concepts we have, so it is fruitless to dream of eliminating it in favor of something simpler or more fundamental.
     From: Donald Davidson (Truth and Predication [2005], 3)
     A reaction: For redundancy theorists, I suppose, truth would be eliminated in favour of 'assertion'. Replacing it with 'satisfaction' doesn't seem very illuminating. Davidson would say 'reference' is more tricky and elusive than truth.
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
Tarski is not a disquotationalist, because you can assign truth to a sentence you can't quote [Davidson]
     Full Idea: It is clearly a mistake to call Tarski a disquotationalist. ...We say of a sentence not at hand (such as 'You gave the right answer to this question last night, but I can't remember what you said') that it is true or false.
     From: Donald Davidson (Truth and Predication [2005], 7)
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
ZFC set theory has only 'pure' sets, without 'urelements' [Reck/Price]
     Full Idea: In standard ZFC ('Zermelo-Fraenkel with Choice') set theory we deal merely with pure sets, not with additional urelements.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §2)
     A reaction: The 'urelements' would the actual objects that are members of the sets, be they physical or abstract. This idea is crucial to understanding philosophy of mathematics, and especially logicism. Must the sets exist, just as the urelements do?
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
Three types of variable in second-order logic, for objects, functions, and predicates/sets [Reck/Price]
     Full Idea: In second-order logic there are three kinds of variables, for objects, for functions, and for predicates or sets.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §5)
     A reaction: It is interesting that a predicate seems to be the same as a set, which begs rather a lot of questions. For those who dislike second-order logic, there seems nothing instrinsically wicked in having variables ranging over innumerable multi-order types.
5. Theory of Logic / I. Semantics of Logic / 4. Satisfaction
'Satisfaction' is a generalised form of reference [Davidson]
     Full Idea: We can think of 'satisfaction' as a generalised form of reference.
     From: Donald Davidson (Truth and Predication [2005], 2)
     A reaction: Just the sort of simple point we novices need from the great minds, to help us see what is going on. One day someone is going to explain Tarski's account of truth in plain English, but probably not in my lifetime.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
'Analysis' is the theory of the real numbers [Reck/Price]
     Full Idea: 'Analysis' is the theory of the real numbers.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §2)
     A reaction: 'Analysis' began with the infinitesimal calculus, which later built on the concept of 'limit'. A continuum of numbers seems to be required to make that work.
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / a. Axioms for numbers
Mereological arithmetic needs infinite objects, and function definitions [Reck/Price]
     Full Idea: The difficulties for a nominalistic mereological approach to arithmetic is that an infinity of physical objects are needed (space-time points? strokes?), and it must define functions, such as 'successor'.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §4)
     A reaction: Many ontologically austere accounts of arithmetic are faced with the problem of infinity. The obvious non-platonist response seems to be a modal or if-then approach. To postulate infinite abstract or physical entities so that we can add 3 and 2 is mad.
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order
Peano Arithmetic can have three second-order axioms, plus '1' and 'successor' [Reck/Price]
     Full Idea: A common formulation of Peano Arithmetic uses 2nd-order logic, the constant '1', and a one-place function 's' ('successor'). Three axioms then give '1 is not a successor', 'different numbers have different successors', and induction.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §2)
     A reaction: This is 'second-order' Peano Arithmetic, though it is at least as common to formulate in first-order terms (only quantifying over objects, not over properties - as is done here in the induction axiom). I like the use of '1' as basic instead of '0'!
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Set-theory gives a unified and an explicit basis for mathematics [Reck/Price]
     Full Idea: The merits of basing an account of mathematics on set theory are that it allows for a comprehensive unified treatment of many otherwise separate branches of mathematics, and that all assumption, including existence, are explicit in the axioms.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §4)
     A reaction: I am forming the impression that set-theory provides one rather good model (maybe the best available) for mathematics, but that doesn't mean that mathematics is set-theory. The best map of a landscape isn't a landscape.
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
Structuralism emerged from abstract algebra, axioms, and set theory and its structures [Reck/Price]
     Full Idea: Structuralism has emerged from the development of abstract algebra (such as group theory), the creation of axiom systems, the introduction of set theory, and Bourbaki's encyclopaedic survey of set theoretic structures.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §2)
     A reaction: In other words, mathematics has gradually risen from one level of abstraction to the next, so that mathematical entities like points and numbers receive less and less attention, with relationships becoming more prominent.
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / b. Varieties of structuralism
Relativist Structuralism just stipulates one successful model as its arithmetic [Reck/Price]
     Full Idea: Relativist Structuralism simply picks one particular model of axiomatised arithmetic (i.e. one particular interpretation that satisfies the axioms), and then stipulates what the elements, functions and quantifiers refer to.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §4)
     A reaction: The point is that a successful model can be offered, and it doesn't matter which one, like having any sort of aeroplane, as long as it flies. I don't find this approach congenial, though having a model is good. What is the essence of flight?
There are 'particular' structures, and 'universal' structures (what the former have in common) [Reck/Price]
     Full Idea: The term 'structure' has two uses in the literature, what can be called 'particular structures' (which are particular relational systems), but also what can be called 'universal structures' - what particular systems share, or what they instantiate.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §6)
     A reaction: This is a very helpful distinction, because it clarifies why (rather to my surprise) some structuralists turn out to be platonists in a new guise. Personal my interest in structuralism has been anti-platonist from the start.
Pattern Structuralism studies what isomorphic arithmetic models have in common [Reck/Price]
     Full Idea: According to 'pattern' structuralism, what we study are not the various particular isomorphic models of arithmetic, but something in addition to them: a corresponding pattern.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §7)
     A reaction: Put like that, we have to feel a temptation to wield Ockham's Razor. It's bad enough trying to give the structure of all the isomorphic models, without seeking an even more abstract account of underlying patterns. But patterns connect to minds..
There are Formalist, Relativist, Universalist and Pattern structuralism [Reck/Price]
     Full Idea: There are four main variants of structuralism in the philosophy of mathematics - formalist structuralism, relativist structuralism, universalist structuralism (with modal variants), and pattern structuralism.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §9)
     A reaction: I'm not sure where Chihara's later book fits into this, though it is at the nominalist end of the spectrum. Shapiro and Resnik do patterns (the latter more loosely); Hellman does modal universalism; Quine does the relativist version. Dedekind?
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / c. Nominalist structuralism
Formalist Structuralism says the ontology is vacuous, or formal, or inference relations [Reck/Price]
     Full Idea: Formalist Structuralism endorses structural methodology in mathematics, but rejects semantic and metaphysical problems as either meaningless, or purely formal, or as inference relations.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §3)
     A reaction: [very compressed] I find the third option fairly congenial, certainly in preference to rather platonist accounts of structuralism. One still needs to distinguish the mathematical from the non-mathematical in the inference relations.
Maybe we should talk of an infinity of 'possible' objects, to avoid arithmetic being vacuous [Reck/Price]
     Full Idea: It is tempting to take a modal turn, and quantify over all possible objects, because if there are only a finite number of actual objects, then there are no models (of the right sort) for Peano Arithmetic, and arithmetic is vacuously true.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §5)
     A reaction: [compressed; Geoffrey Hellman is the chief champion of this view] The article asks whether we are not still left with the puzzle of whether infinitely many objects are possible, instead of existent.
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / d. Platonist structuralism
Universalist Structuralism is based on generalised if-then claims, not one particular model [Reck/Price]
     Full Idea: Universalist Structuralism is a semantic thesis, that an arithmetical statement asserts a universal if-then statement. We build an if-then statement (using quantifiers) into the structure, and we generalise away from any one particular model.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §5)
     A reaction: There remains the question of what is distinctively mathematical about the highly generalised network of inferences that is being described. Presumable the axioms capture that, but why those particular axioms? Russell is cited as an originator.
Universalist Structuralism eliminates the base element, as a variable, which is then quantified out [Reck/Price]
     Full Idea: Universalist Structuralism is eliminativist about abstract objects, in a distinctive form. Instead of treating the base element (say '1') as an ambiguous referring expression (the Relativist approach), it is a variable which is quantified out.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §5)
     A reaction: I am a temperamental eliminativist on this front (and most others) so this is tempting. I am also in love with the concept of a 'variable', which I take to be utterly fundamental to all conceptual thought, even in animals, and not just a trick of algebra.
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
The existence of an infinite set is assumed by Relativist Structuralism [Reck/Price]
     Full Idea: Relativist Structuralism must first assume the existence of an infinite set, otherwise there would be no model to pick, and arithmetical terms would have no reference.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §4)
     A reaction: See Idea 10169 for Relativist Structuralism. They point out that ZFC has an Axiom of Infinity.
8. Modes of Existence / B. Properties / 11. Properties as Sets
Treating predicates as sets drops the predicate for a new predicate 'is a member of', which is no help [Davidson]
     Full Idea: 'Theaetetus is a member of the set of seated objects' doesn't mention the predicate 'sits', but has a new predicate 'is a member of', with no given semantic role. We are back with Plato's problem with the predicate 'instantiates'.
     From: Donald Davidson (Truth and Predication [2005], 7)
     A reaction: Plato's problem is the 'third man' problem - a regress in the explanation. In other words, if we are trying to explain predication, treating predicates as sets gets us nowhere. Just as I always thought. But you have to want explanations.
8. Modes of Existence / E. Nominalism / 6. Mereological Nominalism
A nominalist might avoid abstract objects by just appealing to mereological sums [Reck/Price]
     Full Idea: One way for a nominalist to reject appeal to all abstract objects, including sets, is to only appeal to nominalistically acceptable objects, including mereological sums.
     From: E Reck / M Price (Structures and Structuralism in Phil of Maths [2000], §4)
     A reaction: I'm suddenly thinking that this looks very interesting and might be the way to go. The issue seems to be whether mereological sums should be seen as constrained by nature, or whether they are unrestricted. See Mereology in Ontology...|Intrinsic Identity.
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
The Identity of Indiscernibles is really the same as the verification principle [Jolley]
     Full Idea: Various writers have noted that the Identity of Indiscernibles is really tantamount to the verification principle.
     From: Nicholas Jolley (Leibniz [2005], Ch.3)
     A reaction: Both principles are false, because they are the classic confusion of epistemology and ontology. The fact that you cannot 'discern' a difference between two things doesn't mean that there is no difference. Things beyond verification can still be discussed.
10. Modality / B. Possibility / 6. Probability
Probability can be constrained by axioms, but that leaves open its truth nature [Davidson]
     Full Idea: Kolmogorov's axiomatisation of probability puts clear constraints on the concept of probability, but leaves open whether probability is further characterised as relative frequency, degree of belief, or something else.
     From: Donald Davidson (Truth and Predication [2005], 2)
     A reaction: Davidson cites this to show the limitations of axiomatic approaches to any topic (e.g. sets, truth, arithmetic). The item in question must be treated as a 'primitive'. This always has the feeling of second-best.
15. Nature of Minds / C. Capacities of Minds / 5. Generalisation by mind
Predicates are a source of generality in sentences [Davidson]
     Full Idea: Predicates introduce generality into sentences.
     From: Donald Davidson (Truth and Predication [2005], 7)
     A reaction: Not sure about this. Most words introduce generality. 'From' is a very general word about direction. 'Dogs bark' is as generally about dogs as it is generally about barking.
19. Language / A. Nature of Meaning / 2. Meaning as Mental
If we reject corresponding 'facts', we should also give up the linked idea of 'representations' [Davidson]
     Full Idea: If we give up facts that make entities true, we ought to give up representations at the same time, for the legitimacy of each depends on the legitimacy of the other.
     From: Donald Davidson (Truth and Predication [2005], 2)
     A reaction: Not sure about this, because I'm not sure I know what he means by 'representations'. Surely every sentence is 'about' something? Is that just the references within the sentence, but not the sentence as a whole?
19. Language / A. Nature of Meaning / 4. Meaning as Truth-Conditions
You only understand an order if you know what it is to obey it [Davidson]
     Full Idea: We understand an imperative if and only if we know under what conditions what it orders or commands is obeyed.
     From: Donald Davidson (Truth and Predication [2005], 6)
     A reaction: How could this be wrong? 'Do you understand the order?' 'Yes sir!' 'Well do it then!' 'Do what sir?'
Utterances have the truth conditions intended by the speaker [Davidson]
     Full Idea: An utterance has certain truth conditions only if the speaker intends it to be interpreted as having those truth conditions.
     From: Donald Davidson (Truth and Predication [2005], 3)
     A reaction: This seems to be a concession to the rather sensible things that Grice said about meaning. What about malapropisms? Surely there the speaker does not understand the truth conditions of her own utterance? Truth conditions are in the head?
19. Language / A. Nature of Meaning / 6. Meaning as Use
Meaning involves use, but a sentence has many uses, while meaning stays fixed [Davidson]
     Full Idea: Meaning depends on use, but it is not easy to say how, for uses to which we may put the utterance of a sentence are endless while its meaning remains fixed.
     From: Donald Davidson (Truth and Predication [2005], 6)
     A reaction: Quite so. The password is 'Swordfish' (or 'Sweet marjoram', if you prefer).
19. Language / A. Nature of Meaning / 7. Meaning Holism / a. Sentence meaning
We recognise sentences at once as linguistic units; we then figure out their parts [Davidson]
     Full Idea: Our interest in the parts of sentences is derivative; we recognise at once that sentences are effective linguistic units, while we must figure out or decide what constitutes the meaningful words and particles.
     From: Donald Davidson (Truth and Predication [2005], Intro)
     A reaction: It depends on whether linguistic priority goes to complete thoughts that require expression, or to naming and ostensive definition to relate to elements of the environment. I find it hard to have a strong view on this one. Just So stories?
19. Language / C. Assigning Meanings / 3. Predicates
Modern predicates have 'places', and are sentences with singular terms deleted from the places [Davidson]
     Full Idea: The notion of 'places' in a predicate is the key to the modern concept of a predicate. Any expression obtained from a sentence by deleting one or more singular terms from the sentence counts as a predicate.
     From: Donald Davidson (Truth and Predication [2005], 4)
The concept of truth can explain predication [Davidson]
     Full Idea: My strategy is to show how our grasp of the concept of truth can explain predication.
     From: Donald Davidson (Truth and Predication [2005], 7)
     A reaction: His account of the concept of truth centres on Tarski's theory, but he clearly thinks more is needed than the bare bones offered by Tarski. The point, I think, is that predication is what makes a sentence 'truth-apt'.
19. Language / C. Assigning Meanings / 4. Compositionality
If you assign semantics to sentence parts, the sentence fails to compose a whole [Davidson]
     Full Idea: The puzzle is that once plausible assignments of semantic roles have been made to parts of sentences, the parts do not seem to compose a united whole.
     From: Donald Davidson (Truth and Predication [2005], Intro)
     A reaction: It's not clear to me that a sentence does compose a 'whole', given that you can often add or remove bits from sentences, sometimes without changing the meaning. We often, in speech, assemble sentences before we have thought of their full meaning.
19. Language / C. Assigning Meanings / 6. Truth-Conditions Semantics
Top-down semantic analysis must begin with truth, as it is obvious, and explains linguistic usage [Davidson]
     Full Idea: Truth is the essential semantic concept with which to begin a top-down analysis of sentences, since truth, or lack of it, is the most obvious semantic property of sentences, and provides the clearest explanation of judging and conveying information.
     From: Donald Davidson (Truth and Predication [2005], Intro)
     A reaction: [a bit compressed] Presumably this goes with giving sentences semantic priority. The alternative approach is compositional, and is likely to give reference of terms priority over truth of the sentence. But accurate reference is a sort of truth.
19. Language / D. Propositions / 1. Propositions
'Humanity belongs to Socrates' is about humanity, so it's a different proposition from 'Socrates is human' [Davidson]
     Full Idea: The sentence 'Humanity belongs to Socrates' is about the concept of humanity, unlike the "equivalent" 'Socrates is human', so they express different propositions.
     From: Donald Davidson (Truth and Predication [2005], 5)
     A reaction: [compressed] I like this a lot, because it shows why we should focus on propositions rather than on sentences, or even utterances. And asking what the sentence is 'about' focuses us on the underlying proposition or thought.
19. Language / F. Communication / 6. Interpreting Language / c. Principle of charity
The principle of charity says an interpreter must assume the logical constants [Davidson]
     Full Idea: The principle of charity says that it is unavoidable that the pattern of sentences to which a speaker assents reflects the semantics of the logical constants.
     From: Donald Davidson (Truth and Predication [2005], 3)
     A reaction: That is not all the principle says, of course. Davidson seems to assume classical logic here, with a bivalent semantics. I wonder if all speakers use 'false' in the normal way, as well as 'true'? Do all languages even contain 'true'?
19. Language / F. Communication / 6. Interpreting Language / d. Metaphor
We indicate use of a metaphor by its obvious falseness, or trivial truth [Davidson]
     Full Idea: The sentences that contain metaphors are typically obviously false or trivially true, because these are typically indications that something is intended as a metaphor.
     From: Donald Davidson (Truth and Predication [2005], 6)
     A reaction: A nice point which sounds correct. Metaphors are famous being false, but the 'obvious' falseness signals the metaphor. If a metaphor is only obscurely false, that makes it difficult to read.