20 ideas
| 18365 | If truths are just identical with facts, then truths will make themselves true [David] |
| Full Idea: According to the identity theory of truth, a proposition is true if and only if it is identical with a fact. ...This leads to the unacceptable claim that every true proposition makes itself true (because it is identical to its fact). | |
| From: Marian David (Truth-making and Correspondence [2009], n 14) |
| 18362 | Examples show that truth-making is just non-symmetric, not asymmetric [David] |
| Full Idea: That 'there is at least one proposition' ...is a case where something makes itself true, which generates a counterexample to the natural assumption that truth-making is asymmetric; truth-making, it seems, is merely non-symmetric. | |
| From: Marian David (Truth-making and Correspondence [2009], 4) |
| 18360 | It is assumed that a proposition is necessarily true if its truth-maker exists [David] |
| Full Idea: Friends of the truth-maker principle usually hold that the following states a crucial necessary condition on truth-making: if x makes y true, then, necessarily, if x exists then y is true. | |
| From: Marian David (Truth-making and Correspondence [2009], 2) | |
| A reaction: My objection is that the proposition y is taken to pre-exist, primly awaiting the facts that will award it 'truth'. An ontology that contains an infinity of propositions, most of which so far lack a truth-value, is incoherent. You can have x, but no y! |
| 18358 | Two different propositions can have the same fact as truth-maker [David] |
| Full Idea: Two different propositions can have the same fact as truth-maker. For example, 'L is happy or L is hungry', and 'L is happy or L is thirsty', which are both made true by the fact that L is happy. | |
| From: Marian David (Truth-making and Correspondence [2009], 1) |
| 18355 | What matters is truth-making (not truth-makers) [David] |
| Full Idea: The term 'truthmaker' just labels whatever stands in the truth-making relation to a truth. The truth-making relation is crucial. It would have been just as well to refer to the truth-'maker' principle as the truth-'making' principle. | |
| From: Marian David (Truth-making and Correspondence [2009], 1) | |
| A reaction: This is well said. The commitment of this theory is to something which makes each proposition true. There is no initial commitment to any theories about what sorts of things do the job. |
| 18354 | Correspondence is symmetric, while truth-making is taken to be asymmetric [David] |
| Full Idea: Correspondence appears to be a symmetric relation while truth-making appears to be, or is supposed to be, an asymmetric relation. | |
| From: Marian David (Truth-making and Correspondence [2009], Intro) |
| 18356 | Correspondence is an over-ambitious attempt to explain truth-making [David] |
| Full Idea: Truth-maker theory says that the attempt by correspondence to fill in the generic truth-maker principle with something more informative fails. It is too ambitious, offering a whole zoo of funny facts that are not needed. | |
| From: Marian David (Truth-making and Correspondence [2009], 1) | |
| A reaction: A typical funny fact is a disjunctive fact, which makes 'he is hungry or thirsty' true (when it can just be made true by the simple fact that he is thirsty). |
| 18363 | Correspondence theorists see facts as the only truth-makers [David] |
| Full Idea: Correspondence theorists are committed to the view that, since truth is correspondence with a fact, only facts can make true propositions true. | |
| From: Marian David (Truth-making and Correspondence [2009], 4) |
| 18364 | Correspondence theory likes ideal languages, that reveal the structure of propositions [David] |
| Full Idea: Correspondence theorists tend to promote ideal languages, ...which is intended to mirror perfectly the structure of the propositions it expresses. | |
| From: Marian David (Truth-making and Correspondence [2009], n 03) |
| 18357 | What makes a disjunction true is simpler than the disjunctive fact it names [David] |
| Full Idea: The proposition that 'L is happy or hungry' can be made true by the fact that L is happy. This does not have the same complexity or constituent structure as the proposition it makes true. | |
| From: Marian David (Truth-making and Correspondence [2009], 1) |
| 18359 | One proposition can be made true by many different facts [David] |
| Full Idea: One proposition can be made true by many different facts (such as 'there are some happy dogs'). | |
| From: Marian David (Truth-making and Correspondence [2009], 1) |
| 13338 | '"It is snowing" is true if and only if it is snowing' is a partial definition of the concept of truth [Tarski] |
| Full Idea: Statements of the form '"it is snowing" is true if and only if it is snowing' and '"the world war will begin in 1963" is true if and only if the world war will being in 1963' can be regarded as partial definitions of the concept of truth. | |
| From: Alfred Tarski (The Establishment of Scientific Semantics [1936], p.404) | |
| A reaction: The key word here is 'partial'. Truth is defined, presumably, when every such translation from the object language has been articulated, which is presumably impossible, given the infinity of concatenated phrases possible in a sentence. |
| 13337 | A language: primitive terms, then definition rules, then sentences, then axioms, and finally inference rules [Tarski] |
| Full Idea: For a language, we must enumerate the primitive terms, and the rules of definition for new terms. Then we must distinguish the sentences, and separate out the axioms from amng them, and finally add rules of inference. | |
| From: Alfred Tarski (The Establishment of Scientific Semantics [1936], p.402) | |
| A reaction: [compressed] This lays down the standard modern procedure for defining a logical language. Once all of this is in place, we then add a semantics and we are in business. Natural deduction tries to do without the axioms. |
| 13335 | Semantics is the concepts of connections of language to reality, such as denotation, definition and truth [Tarski] |
| Full Idea: Semantics is the totality of considerations concerning concepts which express connections between expressions of a language and objects and states of affairs referred to by these expressions. Examples are denotation, satisfaction, definition and truth. | |
| From: Alfred Tarski (The Establishment of Scientific Semantics [1936], p.401) | |
| A reaction: Interestingly, he notes that it 'is not commonly recognised' that truth is part of semantics. Nowadays truth seems to be the central concept in most semantics. |
| 13336 | A language containing its own semantics is inconsistent - but we can use a second language [Tarski] |
| Full Idea: People have not been aware that the language about which we speak need by no means coincide with the language in which we speak. ..But the language which contains its own semantics must inevitably be inconsistent. | |
| From: Alfred Tarski (The Establishment of Scientific Semantics [1936], p.402) | |
| A reaction: It seems that Tarski was driven to propose the metalanguage approach mainly by the Liar Paradox. |
| 13339 | A sentence is satisfied when we can assert the sentence when the variables are assigned [Tarski] |
| Full Idea: Here is a partial definition of the concept of satisfaction: John and Peter satisfy the sentential function 'X and Y are brothers' if and only if John and Peter are brothers. | |
| From: Alfred Tarski (The Establishment of Scientific Semantics [1936], p.405) | |
| A reaction: Satisfaction applies to open sentences and truth to closed sentences (with named objects). He uses the notion of total satisfaction to define truth. The example is a partial definition, not just an illustration. |
| 13340 | Satisfaction is the easiest semantical concept to define, and the others will reduce to it [Tarski] |
| Full Idea: It has been found useful in defining semantical concepts to deal first with the concept of satisfaction; both because the definition of this concept presents relatively few difficulties, and because the other semantical concepts are easily reduced to it. | |
| From: Alfred Tarski (The Establishment of Scientific Semantics [1936], p.406) | |
| A reaction: See Idea 13339 for his explanation of satisfaction. We just say that a open sentence is 'acceptable' or 'assertible' (or even 'true') when particular values are assigned to the variables. Then sentence is then 'satisfied'. |
| 13341 | Using the definition of truth, we can prove theories consistent within sound logics [Tarski] |
| Full Idea: Using the definition of truth we are in a position to carry out the proof of consistency for deductive theories in which only (materially) true sentences are (formally) provable. | |
| From: Alfred Tarski (The Establishment of Scientific Semantics [1936], p.407) | |
| A reaction: This is evidently what Tarski saw as the most important first fruit of his new semantic theory of truth. |
| 18361 | A reflexive relation entails that the relation can't be asymmetric [David] |
| Full Idea: An asymmetric relation must be irreflexive: any case of aRa will yield a reductio of the assumption that R is asymmetric. | |
| From: Marian David (Truth-making and Correspondence [2009], 4) |
| 14014 | Space alone, and time alone, will fade away, and only their union has an independent reality [Minkowski] |
| Full Idea: Henceforth, space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union of the two will preserve an independent reality. | |
| From: Hermann Minkowski (Space and Time [1908], Intro) | |
| A reaction: Notice the qualification that it is a 'kind of' union. Deep confusion arises from exaggerating the analogy between space and time. Craig Bourne remarks (2006:157) that this shows independence of measurement, not of reality |