17 ideas
| 9766 | Study vagueness first by its logic, then by its truth-conditions, and then its metaphysics [Fine,K] |
| Full Idea: My investigation of vagueness began with the question 'What is the correct logic of vagueness?', which led to the further question 'What are the correct truth-conditions for a vague language?', which led to questions of meaning and existence. | |
| From: Kit Fine (Vagueness, Truth and Logic [1975], Intro) | |
| A reaction: This is the most perfect embodiment of the strategy of analytical philosophy which I have ever read. It is the strategy invented by Frege in the 'Grundlagen'. Is this still the way to go, or has this pathway slowly sunk into the swamp? |
| 9775 | Excluded Middle, and classical logic, may fail for vague predicates [Fine,K] |
| Full Idea: Maybe classical logic fails for vagueness in Excluded Middle. If 'H bald ∨ ¬(H bald)' is true, then one disjunct is true. But if the second is true the first is false, and the sentence is either true or false, contrary to the borderline assumption. | |
| From: Kit Fine (Vagueness, Truth and Logic [1975], 4) | |
| A reaction: Fine goes on to argue against the implication that we need a special logic for vague predicates. |
| 16489 | Is it possible to state every possible truth about the whole course of nature without using 'not'? [Russell] |
| Full Idea: Imagine a person who knew everything that can be stated without using the word 'not' or some equivalent; would such a person know the whole course of nature, or would he not? | |
| From: Bertrand Russell (Human Knowledge: its scope and limits [1948], 9) | |
| A reaction: Nowadays we might express Russell's thought as 'Does God need the word 'not'?'. Russell's thesis is that such words concern psychology, and not physics. God would need 'not' to describe how human minds work. |
| 9771 | Logic holding between indefinite sentences is the core of all language [Fine,K] |
| Full Idea: If language is like a tree, then penumbral connection (logic holding among indefinite sentences) is the seed from which the tree grows, for it provides an initial repository of truths that are to be retained throughout all growth. | |
| From: Kit Fine (Vagueness, Truth and Logic [1975], 2) | |
| A reaction: A nice incidental insight arising from his investigation of vagueness. People accept one another's reasons even when they are confused, or hopeless at expressing themselves. Nice. |
| 9768 | Vagueness is semantic, a deficiency of meaning [Fine,K] |
| Full Idea: I take vagueness to be a semantic feature, a deficiency of meaning. It is to be distinguished from generality, undecidability, and ambiguity. | |
| From: Kit Fine (Vagueness, Truth and Logic [1975], Intro) | |
| A reaction: Sounds good. If we cut nature at the joints with our language, then nature is going to be too subtle and vast for our finite and gerrymandered language, and so it will break down in tricky situations. But maybe epistemology precedes semantics? |
| 9776 | A thing might be vaguely vague, giving us higher-order vagueness [Fine,K] |
| Full Idea: There is a possibility of 'higher-order vagueness'. The vague may be vague, or vaguely vague, and so on. If J has few hairs on his head than H, then he may be a borderline case of a borderline case. | |
| From: Kit Fine (Vagueness, Truth and Logic [1975], 5) | |
| A reaction: Such slim grey areas can also be characterised as those where you think he is definitely bald, but I am not so sure. |
| 9767 | A vague sentence is only true for all ways of making it completely precise [Fine,K] |
| Full Idea: A vague sentence is (roughly stated) true if and only if it is true for all ways of making it completely precise (the 'super-truth theory'). | |
| From: Kit Fine (Vagueness, Truth and Logic [1975], Intro) | |
| A reaction: Intuitively this sounds quite promising. Personally I think we should focus on the 'proposition' rather than the 'sentence' (where fifteen sentences might be needed before we can agree on the one proposition). |
| 9770 | Logical connectives cease to be truth-functional if vagueness is treated with three values [Fine,K] |
| Full Idea: With a three-value approach, if P is 'blob is pink' and R is 'blob is red', then P&P is indefinite, but P&R is false, and P∨P is indefinite, but P∨R is true. This means the connectives & and ∨ are not truth-functional. | |
| From: Kit Fine (Vagueness, Truth and Logic [1975], 1) | |
| A reaction: The point is that there could then be no logic in any way classical for vague sentences and three truth values. A powerful point. |
| 9772 | Meaning is both actual (determining instances) and potential (possibility of greater precision) [Fine,K] |
| Full Idea: The meaning of an expression is the product of both its actual meaning (what helps determine its instances and counter-instances), and its potential meaning (the possibilities for making it more precise). | |
| From: Kit Fine (Vagueness, Truth and Logic [1975], 2) | |
| A reaction: A modal approach to meaning is gloriously original. Being quite a fan of real modalities (the possibilities latent in actuality), I find this intuitively appealing. |
| 9773 | With the super-truth approach, the classical connectives continue to work [Fine,K] |
| Full Idea: With the super-truth approach, if P is 'blob is pink' and R is 'blob is red', then P&R is false, and P∨R is true, since one of P and R is true and one is false in any complete and admissible specification. It encompasses all 'penumbral truths'. | |
| From: Kit Fine (Vagueness, Truth and Logic [1975], 3) | |
| A reaction: [See Idea 9767 for the super-truth approach, and Idea 9770 for a contrasting view] The approach, which seems quite appealing, is that we will in no circumstances give up basic classical logic, but we will make maximum concessions to vagueness. |
| 9774 | Borderline cases must be under our control, as capable of greater precision [Fine,K] |
| Full Idea: Any borderline case must be under our control, in the sense that it can be settled by making the predicates more precise. | |
| From: Kit Fine (Vagueness, Truth and Logic [1975], 3) | |
| A reaction: Sounds good. Consider an abstract concept like the equator. It is precise on a map of the world, but vague when you are in the middle of the tropics. But we can always form a committee to draw a (widish) line on the ground delineating it. |
| 9769 | Vagueness can be in predicates, names or quantifiers [Fine,K] |
| Full Idea: There are three possible sources of vagueness: the predicates, the names, and the quantifiers. | |
| From: Kit Fine (Vagueness, Truth and Logic [1975], 1) | |
| A reaction: Presumably a vagueness about the domain of discussion would be a vagueness in the quantifier. This is a helpful preliminary division, in the semantic approach to vagueness. |
| 16490 | Some facts about experience feel like logical necessities [Russell] |
| Full Idea: The impossibility of seeing two colours simultaneously in a given direction feels like a logical impossibility. | |
| From: Bertrand Russell (Human Knowledge: its scope and limits [1948], 9) | |
| A reaction: I presume all necessities feel equally necessary. If we distinguish necessities by what gives rise to them (a view I favour) then how strong they 'feel' will be irrelevant. We can see why Russell is puzzled by the phenomenon, though. |
| 16488 | It is hard to explain how a sentence like 'it is not raining' can be found true by observation [Russell] |
| Full Idea: If 'it is not raining' means 'the sentence "it is raining" is false', that makes it almost impossible to understand how a sentence containing the word 'not' can be found true by observation. | |
| From: Bertrand Russell (Human Knowledge: its scope and limits [1948], 9) | |
| A reaction: Russell goes on to explore the general difficulty of deciding negative truths by observation. The same problem arises for truthmaker theory. Obviously I can observe that it isn't raining, but it seems parasitic on observing when it is raining. |
| 19216 | Propositions (such as 'that dog is barking') only exist if their items exist [Williamson] |
| Full Idea: A proposition about an item exists only if that item exists... how could something be the proposition that that dog is barking in circumstances in which that dog does not exist? | |
| From: Timothy Williamson (Necessary Existents [2002], p.240), quoted by Trenton Merricks - Propositions | |
| A reaction: This is a view of propositions I can't make sense of. If I'm under an illusion that there is a dog barking nearby, when there isn't one, can I not say 'that dog is barking'? If I haven't expressed a proposition, what have I done? |
| 16491 | If we define 'this is not blue' as disbelief in 'this is blue', we eliminate 'not' as an ingredient of facts [Russell] |
| Full Idea: We can reintroduce 'not' by a definition: the words 'this is not blue' are defined as expressing disbelief in what is expressed by the words 'this is blue'. In this way the need of 'not' as an indefinable constituent of facts is avoided. | |
| From: Bertrand Russell (Human Knowledge: its scope and limits [1948], 9) | |
| A reaction: This is part of Russell's programme of giving a psychological account of logical connectives. See other ideas from his 1940 and 1948 works. He observes that disbelief is a state just as positive as belief. I love it. |
| 4786 | Russell's 'at-at' theory says motion is to be at the intervening points at the intervening instants [Russell, by Psillos] |
| Full Idea: To reply to Zeno's Arrow Paradox, Russell developed his 'at-at' theory of motion, which says that to move from A to B is to be at the intervening points at the intervening instants. | |
| From: report of Bertrand Russell (Human Knowledge: its scope and limits [1948]) by Stathis Psillos - Causation and Explanation §4.2 | |
| A reaction: I wonder whether Russell's target was actually Zeno, or was it a simplified ontology of points and instants? The ontology will also need identity, to ensure it is the same thing which arrives at each point. |