29 ideas
| 21829 | Philosophy aims to understand how things (broadly understood) hang together (broadly understood) [Sellars] |
| Full Idea: The aim of philosophy, abstractly formulated, is to understand how things in the broadest possible sense of the term hang together in the broadest possible sense of the term. | |
| From: Wilfrid Sellars (Philosophy and Scientific Image of Man [1962], p.3), quoted by Owen Flanagan - The Really Hard Problem 1 'Vocation' | |
| A reaction: I'm happier with broad things than broad hanging together, but to me this sounds about right. |
| 1848 | We are coerced into assent to a truth by reason's violence [Aquinas] |
| Full Idea: We are coerced into assent to a truth by reason's violence. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.10) |
| 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! |
| 1858 | The mind is compelled by necessary truths, but not by contingent truths [Aquinas] |
| Full Idea: Mind is compelled by necessary truths that can't be regarded as false, but not by contingent ones that might be false. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.h to 12) |
| 1852 | For the mind Good is one truth among many, and Truth is one good among many [Aquinas] |
| Full Idea: Good itself as taken in by mind is one truth among others, and truth itself as goal of mind's activity is one good among others. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.reply) |
| 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. |
| 6550 | Reduction requires that an object's properties consist of its constituents' properties and relations [Sellars] |
| Full Idea: The 'Principle of Reducibility' says if an object is a system of objects, then every property of the object must consist in the fact that its constituents have such and such qualities and such and such relations | |
| From: Wilfrid Sellars (Philosophy and Scientific Image of Man [1962], p.27), quoted by William Lycan - Consciousness | |
| A reaction: This sounds to me a more promising attitude to reduction than all this talk of Ernest Nagel's 'Bridge Laws'. If we ask HOW a higher level property arises because of a lower level property, we can describe a mechanism rather than a law. |
| 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. |
| 1860 | Knowledge may be based on senses, but we needn't sense all our knowledge [Aquinas] |
| Full Idea: All our knowledge comes through our senses, but that doesn't mean that everything we know is sensed. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.h to 18) |
| 1855 | If we saw something as totally and utterly good, we would be compelled to will it [Aquinas] |
| Full Idea: Something apprehended to be good and appropriate in any and every circumstance that could be thought of would compel us to will it. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.reply) |
| 1861 | The will is not compelled to move, even if pleasant things are set before it [Aquinas] |
| Full Idea: The will is not compelled to move, for it doesn't have to want the pleasant things set before it. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.h to 21) |
| 1856 | Nothing can be willed except what is good, but good is very varied, and so choices are unpredictable [Aquinas] |
| Full Idea: Nothing can be willed except good, but many and various things are good, and you can't conclude from this that wills are compelled to choose this or that one. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.h to 05) |
| 1849 | Since will is a reasoning power, it can entertain opposites, so it is not compelled to embrace one of them [Aquinas] |
| Full Idea: Reasoning powers can entertain opposite objects. Now will is a reasoning power, so will can entertain opposites and is not compelled to embrace one of them. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.x2) |
| 1853 | Because the will moves by examining alternatives, it doesn't compel itself to will [Aquinas] |
| Full Idea: Because will moves itself by deliberation - a kind of investigation which doesn't prove some one way correct but examines the alternatives - will doesn't compel itself to will. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.reply) |
| 1862 | However habituated you are, given time to ponder you can go against a habit [Aquinas] |
| Full Idea: However habituated you are, given time to ponder you can go against a habit. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.h to 24) |
| 1854 | We must admit that when the will is not willing something, the first movement to will must come from outside the will [Aquinas] |
| Full Idea: We are forced to admit that, in any will that is not always willing, the very first movement to will must come from outside, stimulating the will to start willing. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.reply) | |
| A reaction: cf Nietzsche |
| 1847 | The will must aim at happiness, but can choose the means [Aquinas] |
| Full Idea: The will is compelled by its ultimate goal (to achieve happiness), but not by the means to achieve it. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.07) |
| 1846 | The will can only want what it thinks is good [Aquinas] |
| Full Idea: Will's object is what is good, and so it cannot will anything but what is good. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.06) |
| 1857 | We don't have to will even perfect good, because we can choose not to think of it [Aquinas] |
| Full Idea: The will can avoid actually willing something by avoiding thinking of it, since mental activity is subject to will. In this respect we aren't compelled to will even total happiness, which is the only perfect good. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.h to 07) |
| 1850 | Without free will not only is ethical action meaningless, but also planning, commanding, praising and blaming [Aquinas] |
| Full Idea: If we are not free to will in any way, but are compelled, everything that makes up ethics vanishes: pondering action, exhorting, commanding, punishing, praising, condemning. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.reply) | |
| A reaction: If doesn't require some magical 'free will' to avoid compulsions. All that is needed is freedom to enact your own willing, rather than someone else's. |
| 1851 | Good applies to goals, just as truth applies to ideas in the mind [Aquinas] |
| Full Idea: Good applies to all goals, just as truth applies to all forms mind takes in. | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.reply) | |
| A reaction: In danger of being tautological, if good is understood as no more than the goal of actions. It seems perfectly possibly to pursue a wicked end, and perhaps feel guilty about it. |
| 1859 | Even a sufficient cause doesn't compel its effect, because interference could interrupt the process [Aquinas] |
| Full Idea: Even a sufficient cause doesn't always compel its effect, since it can sometimes be interfered with so that its effect doesn't happen | |
| From: Thomas Aquinas (Quaestiones Disputatae de Malo [1271], Q6.h to 15) |