17 ideas
| 8952 | We reach 'reflective equilibrium' when intuitions and theory completely align [Fisher] |
| Full Idea: A state of 'reflective equilibrium' is when our theory and our intuitions become completely aligned | |
| From: Jennifer Fisher (On the Philosophy of Logic [2008], 12.IV) | |
| A reaction: [Rawls made this concept famous] This is a helpful concept in trying to spell out the ideal which is the dream of believers in 'pure reason' - that there is a goal in which everything comes right. The problem is when people have different intuitions! |
| 8943 | Three-valued logic says excluded middle and non-contradition are not tautologies [Fisher] |
| Full Idea: In three-valued logic (L3), neither the law of excluded middle (p or not-p), nor the law of non-contradiction (not(p and not-p)) will be tautologies. If p has the value 'indeterminate' then so will not-p. | |
| From: Jennifer Fisher (On the Philosophy of Logic [2008], 07.I) | |
| A reaction: I quite accept that the world is full of indeterminate propositions, and that excluded middle and non-contradiction can sometimes be uncertain, but I am reluctant to accept that what is being offered here should be called 'logic'. |
| 8945 | Fuzzy logic has many truth values, ranging in fractions from 0 to 1 [Fisher] |
| Full Idea: In fuzzy logic objects have properties to a greater or lesser degree, and truth values are given as fractions or decimals, ranging from 0 to 1. Not-p is defined as 1-p, and other formula are defined in terms of maxima and minima for sets. | |
| From: Jennifer Fisher (On the Philosophy of Logic [2008], 07.II) | |
| A reaction: The question seems to be whether this is actually logic, or a recasting of probability theory. Susan Haack attacks it. If logic is the study of how truth is preserved as we move between propositions, then 0 and 1 need a special status. |
| 8951 | Classical logic is: excluded middle, non-contradiction, contradictions imply all, disjunctive syllogism [Fisher] |
| Full Idea: For simplicity, we can say that 'classical logic' amounts to the truth of four sentences: 1) either p or not-p; 2) it is not the case that both p and not-p; 3) from p and not-p, infer q; 4) from p or q and not-p, infer q. | |
| From: Jennifer Fisher (On the Philosophy of Logic [2008], 12.I) | |
| A reaction: [She says there are many ways of specifying classical logic] Intuition suggests that 2 and 4 are rather hard to dispute, while 1 is ignoring some grey areas, and 3 is totally ridiculous. There is, of course, plenty of support for 3! |
| 8950 | Logic formalizes how we should reason, but it shouldn't determine whether we are realists [Fisher] |
| Full Idea: Even if one is inclined to be a realist about everything, it is hard to see why our logic should be the determiner. Logic is supposed to formalize how we ought to reason, but whether or not we should be realists is a matter of philosophy, not logic. | |
| From: Jennifer Fisher (On the Philosophy of Logic [2008], 09.I) | |
| A reaction: Nice to hear a logician saying this. I do not see why talk in terms of an object is a commitment to its existence. We can discuss the philosopher's stone, or Arthur's sword, or the Loch Ness monster, or gravitinos, with degrees of commitment. |
| 10369 | How fine-grained Kim's events are depends on how finely properties are individuated [Kim, by Schaffer,J] |
| Full Idea: How fine-grained Kim's events are depends on how finely properties are individuated. | |
| From: report of Jaegwon Kim (Events as property exemplifications [1976]) by Jonathan Schaffer - The Metaphysics of Causation 1.2 | |
| A reaction: I don't actually buy the idea that an event could just be an 'exemplification'. Change seems to be required, and processes, or something like them, must be mentioned. Degrees of fine-graining sound good, though, for processes too. |
| 8976 | If events are ordered triples of items, such things seem to be sets, and hence abstract [Simons on Kim] |
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Full Idea:
If Kim's events are just the ordered triple of |
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| From: comment on Jaegwon Kim (Events as property exemplifications [1976]) by Peter Simons - Events 2.1 | |
| A reaction: You might reply that the object, and maybe the attribute, are concrete, and the time is natural, but the combination really is an abstraction, even though it is located (like the equator). Where is the set of my books located? |
| 8975 | Events cannot be merely ordered triples, but must specify the link between the elements [Kim, by Simons] |
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Full Idea:
Kim's events cannot just be the ordered triple of |
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| From: report of Jaegwon Kim (Events as property exemplifications [1976]) by Peter Simons - Events 2.1 | |
| A reaction: Why should they even be in that particular order? This requirement rather messes up Kim's plan for a very streamlined, Ockhamised ontology. Circles have symmetry at all times. Is 'near Trafalgar Square' a property? |
| 8974 | Events are composed of an object with an attribute at a time [Kim, by Simons] |
| Full Idea: Kim's events are exemplifications by an object of an attribute at a time...It does not make events basic entities, as the three constituents are more basic, but it gives identity conditions (two events are the same if object, attribute and time the same). | |
| From: report of Jaegwon Kim (Events as property exemplifications [1976]) by Peter Simons - Events 2.1 | |
| A reaction: [Aristotle is said to be behind this] I am more sympathetic to this view than the claim that events are primitive. If a pebble is ellipsoid for a million years, is that an event? I think the concept of a 'process' is the most fruitful one to investigate. |
| 8977 | Since properties like self-identity and being 2+2=4 are timeless, Kim must restrict his properties [Simons on Kim] |
| Full Idea: Since some tautologously universal properties such as self-identity or being such that 2+2=4 apply to all things at all times, that is stretching Kim's events too far. Candidate properties need to be realistically restricted, and it is unclear how. | |
| From: comment on Jaegwon Kim (Events as property exemplifications [1976]) by Peter Simons - Events 2.1 | |
| A reaction: You could deploy Schoemaker's concept of natural properties in terms of the source of causal powers, but the problem would be that you were probably hoping to then use Kim's events to define causation. Answer: treat causation as the primitive. |
| 8980 | Kim's theory results in too many events [Simons on Kim] |
| Full Idea: The criticism most frequently levelled against Kim's theory is that it results in an unacceptable plurality of finely differentiated events, because of the requirement for identity of the constituent property. | |
| From: comment on Jaegwon Kim (Events as property exemplifications [1976]) by Peter Simons - Events 4.4 | |
| A reaction: This may mean that the Battle of Waterloo was several trillion events, which seems daft to the historian, but it doesn't to the physicist. A cannon firing is indeed an accumulation of lots of little events. |
| 8946 | We could make our intuitions about heaps precise with a million-valued logic [Fisher] |
| Full Idea: We could construct a 1,000,000-valued logic that would allow our intuitions concerning a heap to vary exactly with the amount of sand in the heap. | |
| From: Jennifer Fisher (On the Philosophy of Logic [2008]) | |
| A reaction: Presumably only an infinite number of grains of sand would then produce a true heap, and even one grain would count as a bit of a heap, which must both be wrong, so I can't see this helping much. |
| 8944 | Vagueness can involve components (like baldness), or not (like boredom) [Fisher] |
| Full Idea: Vague terms come in at least two different kinds: those whose constituent parts come in discrete packets (bald, rich, red) and those that don't (beauty, boredom, niceness). | |
| From: Jennifer Fisher (On the Philosophy of Logic [2008], 07.II) | |
| A reaction: The first group seem to be features of the external world, and the second all occur in the mind. Baldness may be vague, but presumably hairs are (on the whole) not. Nature doesn't care whether someone is actually 'bald' or not. |
| 8941 | We can't explain 'possibility' in terms of 'possible' worlds [Fisher] |
| Full Idea: Explaining 'it is possible that p' by saying p is true in at least one possible world doesn't get me very far. If I don't understand what possibility is, then appealing to possible worlds is not going to do me much good. | |
| From: Jennifer Fisher (On the Philosophy of Logic [2008], 06.III) | |
| A reaction: This seems so blatant that I assume friends of possible worlds will have addressed the problem. Note that you will also need to understand 'possible' to define necessity as 'true in all possible worlds'. Necessarily-p is not-possibly-not-p. |
| 8947 | If all truths are implied by a falsehood, then not-p might imply both q and not-q [Fisher] |
| Full Idea: If all truths are implied by a falsehood, then 'if there are no trees in the park then there is no shade' and 'if there are no trees in the park there is plenty of shade' both come out as true. Intuitively, though, the second one is false. | |
| From: Jennifer Fisher (On the Philosophy of Logic [2008], 08.I) | |
| A reaction: The rule that a falsehood implies all truths must be the weakest idea in classical logic, if it actually implies a contradiction. This means we must take an interest in relevance logics. |
| 8949 | In relevance logic, conditionals help information to flow from antecedent to consequent [Fisher] |
| Full Idea: A good account of relevance logic suggests that a conditional will be true when the flow of information is such that a conditional is the device that helps information to flow from the antecedent to the consequent. | |
| From: Jennifer Fisher (On the Philosophy of Logic [2008], 08.III) | |
| A reaction: Hm. 'If you are going out, you'll need an umbrella'. This passes on information about 'out', but also brings in new information. 'If you are going out, I'm leaving you'. What flows is an interpretation of the antecedent. Tricky. |
| 19708 | Rational internal belief is conviction that a proposition enhances a belief system [Foley, by Vahid] |
| Full Idea: In Foley's subjective internalist account it is egocentrically rational for an agent to believe a proposition only if he would think on deep reflection that believing it is conducive to having an accurate and comprehensive belief system. | |
| From: report of Richard Foley (The Theory of Epistemic Rationality [1987], 2.1 B) by Hamid Vahid - Externalism/Internalism | |
| A reaction: I like this idea, because it indicates the link between internalism and coherence about justification. I don't think you can be an externalist coherence theorist for justification. [Reminder: Paul Thagard is the best writer on coherence]. |