15 ideas
| 20728 | Metaphysics is hopeless with its present epistemology; common-sense realism is needed [Colvin] |
| Full Idea: Despair over metaphysics will not change until it has shaken off the incubus of a perverted epistemology, which has left thought in a hopeless tangle - until common-sense critical realism is made the starting point for investigating reality. | |
| From: Stephen S. Colvin (The Common-Sense View of Reality [1902], p.144) | |
| A reaction: It seems to me that this is what has happened to analytic metaphysics since Kripke. Careful discussions about the nature of an object, or a category, or a property, are relying on unquestioned robust realism. Quite right too. |
| 18344 | Truth and falsehood must track what does or doesn't exist [Bigelow] |
| Full Idea: If something is true, then it would not be possible for it to be false unless either certain things were to exist which don't, or else certain things had not existed which do. | |
| From: John Bigelow (The Reality of Numbers [1988], 19) | |
| A reaction: This is described by Rami as Bigelow's 'famous' formulation of the idea that 'truth supervenes on being' in a general way. An immediate question would be about fictions. Is Malvolio a stupid man, given that he doesn't exist? We must stretch 'exist'. |
| 15375 | If terms change their designations in different states, they are functions from states to objects [Fitting] |
| Full Idea: The common feature of every designating term is that designation may change from state to state - thus it can be formalized by a function from states to objects. | |
| From: Melvin Fitting (Intensional Logic [2007], 3) | |
| A reaction: Specifying the objects sounds OK, but specifying states sounds rather tough. |
| 15376 | Intensional logic adds a second type of quantification, over intensional objects, or individual concepts [Fitting] |
| Full Idea: To first order modal logic (with quantification over objects) we can add a second kind of quantification, over intensions. An intensional object, or individual concept, will be modelled by a function from states to objects. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.3) |
| 15378 | Awareness logic adds the restriction of an awareness function to epistemic logic [Fitting] |
| Full Idea: Awareness logic enriched Hintikka's epistemic models with an awareness function, mapping each state to the set of formulas we are aware of at that state. This reflects some bound on the resources we can bring to bear. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.6.1) | |
| A reaction: [He cites Fagin and Halpern 1988 for this] |
| 15379 | Justication logics make explicit the reasons for mathematical truth in proofs [Fitting] |
| Full Idea: In justification logics, the logics of knowledge are extended by making reasons explicit. A logic of proof terms was created, with a semantics. In this, mathematical truths are known for explicit reasons, and these provide a measure of complexity. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.6.1) |
| 11026 | Classical logic is deliberately extensional, in order to model mathematics [Fitting] |
| Full Idea: Mathematics is typically extensional throughout (we write 3+2=2+3 despite the two terms having different meanings). ..Classical first-order logic is extensional by design since it primarily evolved to model the reasoning of mathematics. | |
| From: Melvin Fitting (Intensional Logic [2007], §1) |
| 11028 | λ-abstraction disambiguates the scope of modal operators [Fitting] |
| Full Idea: λ-abstraction can be used to abstract and disambiguate a predicate. De re is [λx◊P(x)](f) - f has the possible-P property - and de dicto is ◊[λxP(x)](f) - possibly f has the P-property. Also applies to □. | |
| From: Melvin Fitting (Intensional Logic [2007], §3.3) | |
| A reaction: Compare the Barcan formula. Originated with Church in the 1930s, and Carnap 1947, but revived by Stalnaker and Thomason 1968. Because it refers to the predicate, it has a role in intensional versions of logic, especially modal logic. |
| 20726 | We can only distinguish self from non-self if there is an inflexible external reality [Colvin] |
| Full Idea: Were there no inflexible reality outside of the individual, opposing and limiting it, knowledge of the self and the non-self would never develop. | |
| From: Stephen S. Colvin (The Common-Sense View of Reality [1902], p.140) | |
| A reaction: Presumably opponents would have to say that such 'knowledge' is an illusion. This is in no way a conclusive argument, but I approach the problem of realism in quest of the best explanation, and this idea is important evidence. |
| 20727 | Common-sense realism rests on our interests and practical life [Colvin] |
| Full Idea: It is the determination of the external world from the practical standpoint, from the standpoint of interest, that may be defined as the common-sense view of reality. | |
| From: Stephen S. Colvin (The Common-Sense View of Reality [1902], p.141) | |
| A reaction: Probably more appropriately named the 'pragmatic' view of reality. Relying on what is 'practical' seems to offer some objectivity, but relying on 'interest' rather less so. Can I be an anti-realist when life goes badly, and a realist when it goes well? |
| 20729 | Arguments that objects are unknowable or non-existent assume the knower's existence [Colvin] |
| Full Idea: Arguments for the absolute unknowability or non-existence of an external object only works by assuming that another external object, an individual, is known completely in so far as that individual expresses a judgement about an external object. | |
| From: Stephen S. Colvin (The Common-Sense View of Reality [1902], p.145) | |
| A reaction: Anti-realism is a decay that eats into everything. You can't doubt all the externals without doubting all the internals as well. |
| 20730 | If objects are doubted because their appearances change, that presupposes one object [Colvin] |
| Full Idea: If objects are doubted because the same object appears differently at different times and circumstances, in order that this judgement shall have weight it must be assumed that the object under question is the same in its different presentations. | |
| From: Stephen S. Colvin (The Common-Sense View of Reality [1902], p.145) | |
| A reaction: [compressed] Scepticism could eat into the underlying object as well. Is the underlying object a 'substrate'? If so, what's that? Is the object just a bundle of a properties? If so, there is no underlying object. |
| 20731 | The idea that everything is relations is contradictory; relations are part of the concept of things [Colvin] |
| Full Idea: The doctrine [that all we can know is the relations between subject and object] is in its essence self-contradictory, since our very idea of thing implies that it is something in relation either actually or potentially. | |
| From: Stephen S. Colvin (The Common-Sense View of Reality [1902], p.150) | |
| A reaction: Ladyman and Ross try to defend an account of reality based entirely on relations. I'm with Colvin on this one. All accounts of reality based either on pure relations or pure functions have a huge hole in their theory. |
| 15377 | Definite descriptions pick out different objects in different possible worlds [Fitting] |
| Full Idea: Definite descriptions pick out different objects in different possible worlds quite naturally. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.4) | |
| A reaction: A definite description can pick out the same object in another possible world, or a very similar one, or an object which has almost nothing in common with the others. |
| 14409 | I am a presentist, and all language and common sense supports my view [Bigelow] |
| Full Idea: I am a presentist: nothing exists which is not present. Everyone believed this until the nineteenth century; it is writing into the grammar of natural languages; it is still assumed in everyday life, even by philosophers who deny it. | |
| From: John Bigelow (Presentism and Properties [1996], p.36), quoted by Trenton Merricks - Truth and Ontology | |
| A reaction: The most likely deniers of presentism seem to be physicists and cosmologists who have overdosed on Einstein. On the whole I vote for presentism, but what justifies truths about the past and future. Traces existing in the present? |