20 ideas
13734 | Modern Quinean metaphysics is about what exists, but Aristotelian metaphysics asks about grounding [Schaffer,J] |
Full Idea: On the now dominant Quinean view, metaphysics is about what there is (such as properties, meanings and numbers). I will argue for the revival of a more traditional Aristotelian view, on which metaphysics is about what grounds what. | |
From: Jonathan Schaffer (On What Grounds What [2009], Intro) | |
A reaction: I find that an enormously helpful distinction, and support the Aristotelian view. Schaffer's general line is that what exists is fairly uncontroversial and dull, but the interesting truths about the world emerge when we grasp its structure. |
13751 | If you tore the metaphysics out of philosophy, the whole enterprise would collapse [Schaffer,J] |
Full Idea: Traditional metaphysics is so tightly woven into the fabric of philosophy that it cannot be torn out without the whole tapestry unravelling. | |
From: Jonathan Schaffer (On What Grounds What [2009], 2.3) | |
A reaction: I often wonder why the opponents of metaphysics still continue to do philosophy. I don't see how you address questions of ethics, or philosophy of mathematics (etc) without coming up against highly general and abstract over-questions. |
13743 | We should not multiply basic entities, but we can have as many derivative entities as we like [Schaffer,J] |
Full Idea: Occam's Razor should only be understood to concern substances: do not multiply basic entities without necessity. There is no problem with the multiplication of derivative entities - they are an 'ontological free lunch'. | |
From: Jonathan Schaffer (On What Grounds What [2009], 2.1) | |
A reaction: The phrase 'ontological free lunch' comes from Armstrong. This is probably what Occam meant. A few extra specks of dust, or even a few more numbers (thank you, Cantor!) don't seem to challenge the principle. |
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. |
13741 | If 'there are red roses' implies 'there are roses', then 'there are prime numbers' implies 'there are numbers' [Schaffer,J] |
Full Idea: We can automatically infer 'there are roses' from 'there are red roses' (with no shift in the meaning of 'roses'). Likewise one can automatically infer 'there are numbers' from 'there are prime numbers'. | |
From: Jonathan Schaffer (On What Grounds What [2009], 2.1) | |
A reaction: He similarly observes that the atheist's 'God is a fictional character' implies 'there are fictional characters'. Schaffer is not committing to a strong platonism with his claim - merely that the existence of numbers is hardly worth disputing. |
13748 | Grounding is unanalysable and primitive, and is the basic structuring concept in metaphysics [Schaffer,J] |
Full Idea: Grounding should be taken as primitive, as per the neo-Aristotelian approach. Grounding is an unanalyzable but needed notion - it is the primitive structuring conception of metaphysics. | |
From: Jonathan Schaffer (On What Grounds What [2009], 2.2) | |
A reaction: [he cites K.Fine 1991] I find that this simple claim clarifies the discussions of Kit Fine, where you are not always quite sure what the game is. I agree fully with it. It makes metaphysics interesting, where cataloguing entities is boring. |
13747 | Supervenience is just modal correlation [Schaffer,J] |
Full Idea: Supervenience is mere modal correlation. | |
From: Jonathan Schaffer (On What Grounds What [2009], 2.2) |
13744 | The cosmos is the only fundamental entity, from which all else exists by abstraction [Schaffer,J] |
Full Idea: My preferred view is that there is only one fundamental entity - the whole concrete cosmos - from which all else exists by abstraction. | |
From: Jonathan Schaffer (On What Grounds What [2009], 2.1) | |
A reaction: This looks to me like weak anti-realism - that there are no natural 'joints' in nature - but I don't think Schaffer intends that. I take the joints to be fundamentals, which necessitates that the cosmos has parts. His 'abstraction' is clearly a process. |
13739 | Maybe categories are just the different ways that things depend on basic substances [Schaffer,J] |
Full Idea: Maybe the categories are determined by the different grounding relations, ..so that categories just are the ways things depend on substances. ...Categories are places in the dependence ordering. | |
From: Jonathan Schaffer (On What Grounds What [2009], 1.3) |
13742 | There exist heaps with no integral unity, so we should accept arbitrary composites in the same way [Schaffer,J] |
Full Idea: I am happy to accept universal composition, on the grounds that there are heaps, piles etc with no integral unity, and that arbitrary composites are no less unified than heaps. | |
From: Jonathan Schaffer (On What Grounds What [2009], 2.1 n11) | |
A reaction: The metaphysical focus is then placed on what constitutes 'integral unity', which is precisely the question which most interested Aristotle. Clearly if there is nothing more to an entity than its components, scattering them isn't destruction. |
13752 | The notion of 'grounding' can explain integrated wholes in a way that mere aggregates can't [Schaffer,J] |
Full Idea: The notion of grounding my capture a crucial mereological distinction (missing from classical mereology) between an integrated whole with genuine unity, and a mere aggregate. x is an integrated whole if it grounds its proper parts. | |
From: Jonathan Schaffer (On What Grounds What [2009], 3.1) | |
A reaction: That gives a nice theoretical notion, but if you remove each of the proper parts, does x remain? Is it a bare particular? I take it that it will have to be an abstract principle, the one Aristotle was aiming at with his notion of 'form'. Schaffer agrees. |
13749 | Belief in impossible worlds may require dialetheism [Schaffer,J] |
Full Idea: One motivation for dialetheism is the view that there are impossible worlds. | |
From: Jonathan Schaffer (On What Grounds What [2009], 2.3) |
13740 | 'Moorean certainties' are more credible than any sceptical argument [Schaffer,J] |
Full Idea: A 'Moorean certainty' is when something is more credible than any philosopher's argument to the contrary. | |
From: Jonathan Schaffer (On What Grounds What [2009], 2.1) | |
A reaction: The reference is to G.E. Moore's famous claim that the existence of his hand is more certain than standard sceptical arguments. It sounds empiricist, but they might be parallel rational truths, of basic logic or arithmetic. |
23222 | A soul with physical extension is more likely than an immaterial soul that moves bodies [Elizabeth] |
Full Idea: I would find it easier to concede matter and extension to the soul than to concede that an immaterial thing could move and be moved by a body. | |
From: Elizabeth, Princess of Bohemia (Letters to Descartes [1643], p.42), quoted by Matthew Cobb - The Idea of the Brain 2 | |
A reaction: Very nicely expressed! I'm trying to imagine a ghost which finds itself stuck with a physical body which it has to drag around like a reluctant dog. She is stating the classic interaction problem which plagues all mind-body dualism. |