8 ideas
| 21597 | Logical connectives have the highest precision, yet are infected by the vagueness of true and false [Russell, by Williamson] |
| Full Idea: Russell says the best chance of avoiding vagueness are the logical connectives. ...But the vagueness of 'true' and 'false' infects the logical connectives too. All words are vague. Russell concludes that all language is vague. | |
| From: report of Bertrand Russell (Vagueness [1923]) by Timothy Williamson - Vagueness 2.4 | |
| A reaction: This relies on the logical connectives being defined semantically, in terms of T and F, but that is standard. Presumably the formal uninterpreted syntax is not vague. |
| 9051 | Since natural language is not precise it cannot be in the province of logic [Russell, by Keefe/Smith] |
| Full Idea: Russell takes it that logic assumes precision, and since natural language is not precise it cannot be in the province of logic at all. | |
| From: report of Bertrand Russell (Vagueness [1923]) by R Keefe / P Smith - Intro: Theories of Vagueness §1 | |
| A reaction: I find this view congenial. It seems to me that the necessary prelude to logic is to do everything you can to eliminate ambiguity and vagueness from the sentences at issue. We want the proposition, or logical form. If there isn't one, forget it? |
| 9054 | Vagueness is only a characteristic of representations, such as language [Russell] |
| Full Idea: Vagueness and precision alike are characteristics which can only belong to a representation, of which language is an example. | |
| From: Bertrand Russell (Vagueness [1923], p.62) | |
| A reaction: Russell was the first to tackle the question of vagueness, and he may have got it right. If we are unable to decide which set an object belongs in (red or orange) that is a problem for our conceptual/linguistic scheme. The object still has a colour! |
| 10558 | Abstract objects are actually constituted by the properties by which we conceive them [Zalta] |
| Full Idea: Where for ordinary objects one can discover the properties they exemplify, abstract objects are actually constituted or determined by the properties by which we conceive them. I use the technical term 'x encodes F' for this idea. | |
| From: Edward N. Zalta (Deriving Kripkean Claims with Abstract Objects [2006], 2 n2) | |
| A reaction: One might say that whereas concrete objects can be dubbed (in the Kripke manner), abstract objects can only be referred to by descriptions. See 10557 for more technicalities about Zalta's idea. |
| 8793 | If observation is knowledge, it is not just an experience; it is a justification in the space of reasons [Sellars] |
| Full Idea: In characterizing an observational episode or state as 'knowing', we are not giving an empirical description of it; we are placing it in the logical space of reasons, of justifying and being able to justify what one says. | |
| From: Wilfrid Sellars (Does Emp.Knowledge have Foundation? [1956], p.123) | |
| A reaction: McDowell has made the Kantian phrase 'the logical space of reasons' very popular. This is a very nice statement of the internalist view of justification, with which I sympathise more and more. It is a rationalist coherentist view. It needn't be mystical! |
| 8792 | Observations like 'this is green' presuppose truths about what is a reliable symptom of what [Sellars] |
| Full Idea: Observational knowledge of any particular fact, e.g. that this is green, presupposes that one knows general facts of the form 'X is a reliable symptom of Y'. | |
| From: Wilfrid Sellars (Does Emp.Knowledge have Foundation? [1956], p.123) | |
| A reaction: This is a nicely observed version of the regress problem with justification. I would guess that foundationalists would simply deny that this further knowledge is required; 'this is green' arises out of the experience, but it is not an inference. |
| 8791 | The concept of 'green' involves a battery of other concepts [Sellars] |
| Full Idea: One can only have the concept of green by having a whole battery of concepts of which it is one element. | |
| From: Wilfrid Sellars (Does Emp.Knowledge have Foundation? [1956], p.120) | |
| A reaction: This points in the direction of holism about language and thought, but need not imply it. It might be that concepts have to be learned in small families. It is not clear, though, what is absolutely essential to 'green', except that it indicates colour. |
| 10557 | Abstract objects are captured by second-order modal logic, plus 'encoding' formulas [Zalta] |
| Full Idea: My object theory is formulated in a 'syntactically second-order' modal predicate calculus modified only so as to admit a second kind of atomic formula ('xF'), which asserts that object x 'encodes' property F. | |
| From: Edward N. Zalta (Deriving Kripkean Claims with Abstract Objects [2006], p.2) | |
| A reaction: This is summarising Zalta's 1983 theory of abstract objects. See Idea 10558 for Zalta's idea in plain English. |