28 ideas
| 12036 | Xenophanes began the concern with knowledge [Annas] |
| Full Idea: Xenophanes begins a long concern with knowledge and its grounds. | |
| From: Julia Annas (Ancient Philosophy: very short introduction [2000], Intro) | |
| A reaction: Having that on his cv ought to make Xenophanes more famous than he is. |
| 12046 | Plato was the first philosopher who was concerned to systematize his ideas [Annas] |
| Full Idea: In the ancient world Plato was seen as a pivotal figure, the first philosopher who was concerned to systematize his ideas. | |
| From: Julia Annas (Ancient Philosophy: very short introduction [2000], Ch.6) |
| 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. |
| 8525 | Relations need terms, so they must be second-order entities based on first-order tropes [Campbell,K] |
| Full Idea: Because there cannot be relations without terms, in a meta-physic that makes first-order tropes the terms of all relations, relational tropes must belong to a second, derivative order. | |
| From: Keith Campbell (The Metaphysic of Abstract Particulars [1981], §8) | |
| A reaction: The admission that there could be a 'derivative order' may lead to trouble for trope theory. Ostrich Nominalists could say that properties themselves are derivative second-order abstractions from indivisible particulars. Russell makes them first-order. |
| 8518 | Events are trope-sequences, in which tropes replace one another [Campbell,K] |
| Full Idea: Events are widely acknowledged to be particulars, but they are plainly not ordinary concrete particulars. They are best viewed as trope-sequences, in which one condition gives way to another. They are changes in which tropes replace one another. | |
| From: Keith Campbell (The Metaphysic of Abstract Particulars [1981], §3) | |
| A reaction: If nothing exists except bundles of tropes, it is worth asking WHY one trope would replace another. Some tropes are active (i.e. they are best described as 'powers'). |
| 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. |
| 8513 | Two red cloths are separate instances of redness, because you can dye one of them blue [Campbell,K] |
| Full Idea: If we have two cloths of the very same shade of redness, we can show there are two cloths by burning one and leaving the other unaffected; we show there are two cases of redness in the same way: dye one blue, leaving the other unaffected. | |
| From: Keith Campbell (The Metaphysic of Abstract Particulars [1981], §1) | |
| A reaction: This has to be one of the basic facts of the problem accepted by everyone. If you dye half of one of the pieces, was the original red therefore one instance or two? Has it become two? How many red tropes are there in a red cloth? |
| 8514 | Red could only recur in a variety of objects if it was many, which makes them particulars [Campbell,K] |
| Full Idea: If there are a varied group of red objects, the only element that recurs is the colour. But it must be the colour as a particular (a 'trope') that is involved in the recurrence, for only particulars can be many in the way required for recurrence. | |
| From: Keith Campbell (The Metaphysic of Abstract Particulars [1981], §1) | |
| A reaction: This claim seems to depend on the presupposition that rednesses are countable things, but it is tricky trying to count the number of blue tropes in the sky. |
| 8522 | Tropes solve the Companionship Difficulty, since the resemblance is only between abstract particulars [Campbell,K] |
| Full Idea: The 'companionship difficulty' cannot arise if the members of the resemblance class are tropes rather than whole concrete particulars. The instances of having a heart, as abstract particulars, are quite different from instances of having a kidney. | |
| From: Keith Campbell (The Metaphysic of Abstract Particulars [1981], §6) | |
| A reaction: The companionship difficulty seems worst if you base your account of properties just on being members of a class. Any talk of resemblance eventually has to talk about 'respects' of resemblance. Is a trope a respect? Is a mode an object? |
| 8523 | Tropes solve the Imperfect Community problem, as they can only resemble in one respect [Campbell,K] |
| Full Idea: The 'problem of imperfect community' cannot arise where our resemblance sets are sets of tropes. Tropes, by their very nature and mode of differentiation can only resemble in one respect. | |
| From: Keith Campbell (The Metaphysic of Abstract Particulars [1981], §6) | |
| A reaction: You arrive at very different accounts of what resemblance means according to how you express the problem verbally. We can only find a solution through thinking which transcends language. Heresy! |
| 8524 | Trope theory makes space central to reality, as tropes must have a shape and size [Campbell,K] |
| Full Idea: The metaphysics of abstract particulars gives a central place to space, or space-time, as the frame of the world. ...Tropes are, of their essence, regional, which carries with it the essential presence of shape and size in any trope occurrence. | |
| From: Keith Campbell (The Metaphysic of Abstract Particulars [1981], §7) | |
| A reaction: Trope theory has a problem with Aristotle's example (Idea 557) of what happens when white is mixed with white. Do two tropes become one trope if you paint on a second coat of white? How can particulars merge? How can abstractions merge? |
| 8521 | Nominalism has the problem that without humans nothing would resemble anything else [Campbell,K] |
| Full Idea: The objection to nominalism is its consequence that if there were no human race (or other living things), nothing would be like anything else. | |
| From: Keith Campbell (The Metaphysic of Abstract Particulars [1981], §6) | |
| A reaction: Anti-realists will be unflustered by this difficulty. Personally it strikes me as obvious that some aspects of resemblance are part of reality which we did not contribute. This I take to be a contingent fact, founded on the existence of natural kinds. |
| 8515 | Tropes are basic particulars, so concrete particulars are collections of co-located tropes [Campbell,K] |
| Full Idea: If tropes are basic particulars, then concrete particulars count as dependent realities. They are collections of co-located tropes, depending on these tropes as a fleet does upon its component ships. | |
| From: Keith Campbell (The Metaphysic of Abstract Particulars [1981], §2) | |
| A reaction: If I sail my yacht through a fleet, do I become part of it? Presumably trope theory could avoid a bundle view of objects. A bare substratum could be a magnet which attracts tropes. |
| 8519 | Bundles must be unique, so the Identity of Indiscernibles is a necessity - which it isn't! [Campbell,K] |
| Full Idea: Each individual is distinct from each other individual, so the bundle account of objects requires each bundle to be different from every other bundle. So the Identity of Indiscernibles must be a necessary truth, which, unfortunately, it is not. | |
| From: Keith Campbell (The Metaphysic of Abstract Particulars [1981], §5) | |
| A reaction: Clearly the Identity of Indiscernibles is not a necessary truth (consider just two identical spheres). Location and time must enter into it. Could we not add a further individuation requirement to the necessary existence of a bundle? (Quinton) |
| 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. |
| 4033 | Two pure spheres in non-absolute space are identical but indiscernible [Campbell,K] |
| Full Idea: The Identity of Indiscernibles is not a necessary truth. It fails in possible worlds where there are two identical spheres in a non-absolute space, or worlds without beginning or end where events are exactly cyclically repeated. | |
| From: Keith Campbell (The Metaphysic of Abstract Particulars [1981], §5) | |
| A reaction: The principle was always very suspect, and these seem nice counterexamples. As so often, epistemology and ontology had become muddled. |
| 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. |
| 8512 | Abstractions come before the mind by concentrating on a part of what is presented [Campbell,K] |
| Full Idea: An item is abstract if it is got before the mind by an act of abstraction, that is, by concentrating attention on some, but not all, of what is presented. | |
| From: Keith Campbell (The Metaphysic of Abstract Particulars [1981], §1) | |
| A reaction: I think this point is incredibly important. Pure Fregean semantics tries to leave out the psychological component, and yet all the problems in semantics concern various sorts of abstraction. Imagination is the focus of the whole operation. |
| 12037 | Euripides's Medea is a key case of reason versus the passions [Annas] |
| Full Idea: Euripides's Medea has remained a key case for discussion of reason and the passions. | |
| From: Julia Annas (Ancient Philosophy: very short introduction [2000], Ch.1) |
| 12040 | Virtue is a kind of understanding of moral value [Annas] |
| Full Idea: There is a widespread view in ancient ethics that virtue is a kind of understanding of moral value. | |
| From: Julia Annas (Ancient Philosophy: very short introduction [2000], Ch.3) | |
| A reaction: In Aristotle's case, this coincides with his apparent view that 'understanding' is the aim of all areas of human thought. See Idea 12038. |
| 8517 | Causal conditions are particular abstract instances of properties, which makes them tropes [Campbell,K] |
| Full Idea: The conditions in causal statements are usually particular cases of properties. A collapse results from the weakness of this cable (not any other). This is specific to a time and place; it is an abstract particular. It is, in short, a trope. | |
| From: Keith Campbell (The Metaphysic of Abstract Particulars [1981], §3) | |
| A reaction: The fan of universals could counter this by saying that the collapse results from this unique combination of universals. Resemblance nominalist can equally build an account on the coincidence of certain types of concrete particulars. |
| 8516 | Davidson can't explain causation entirely by events, because conditions are also involved [Campbell,K] |
| Full Idea: Not all singular causal statements are of Davidson's event-event type. Many involve conditions, so there are condition-event (weakness/collapse), event-condition (explosion/movement), and condition-condition (hot/warming) causal connections. | |
| From: Keith Campbell (The Metaphysic of Abstract Particulars [1981], §3) | |
| A reaction: Fans of Davidson need to reduce conditions to events. The problem of individuation keeps raising its head. Davidson makes it depend on description. Kim looks good, because events, and presumably conditions, reduce to something small and precise. |