32 ideas
| 23728 | Analysis aims to express the full set of platitudes surrounding a given concept [Smith,M] |
| Full Idea: The aim of analysis is to give us knowledge of all and only the platitudes surrounding our use of the concept that is up for analysis. | |
| From: Michael Smith (The Moral Problem [1994], 1.10) | |
| A reaction: His earlier specimen concept is 'redness'. For other concepts there might be considerable disagreement about which propositions are or are not the relevant platitudes. Smith emphasises that analysis need not be reductive. |
| 23744 | Defining a set of things by paradigms doesn't pin them down enough [Smith,M] |
| Full Idea: The discussion of colour concepts shows that permutation problems arise when a set of concepts, acquired inter alia via the presentation of paradigms, is largely interdefined. | |
| From: Michael Smith (The Moral Problem [1994], 5.9) | |
| A reaction: Smith says that our normative moral concepts are largely interdefined in this way. The 'permutation' problem is that they can change places in the definition set, and so their intrinsic individual character is not pinned down. Sounds right. |
| 13838 | A decent modern definition should always imply a semantics [Hacking] |
| Full Idea: Today we expect that anything worth calling a definition should imply a semantics. | |
| From: Ian Hacking (What is Logic? [1979], §10) | |
| A reaction: He compares this with Gentzen 1935, who was attempting purely syntactic definitions of the logical connectives. |
| 13833 | 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking] |
| Full Idea: 'Dilution' (or 'Thinning') provides an essential contrast between deductive and inductive reasoning; for the introduction of new premises may spoil an inductive inference. | |
| From: Ian Hacking (What is Logic? [1979], §06.2) | |
| A reaction: That is, inductive logic (if there is such a thing) is clearly non-monotonic, whereas classical inductive logic is monotonic. |
| 13834 | Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking] |
| Full Idea: If A |- B and B |- C, then A |- C. This generalises to: If Γ|-A,Θ and Γ,A |- Θ, then Γ |- Θ. Gentzen called this 'cut'. It is the transitivity of a deduction. | |
| From: Ian Hacking (What is Logic? [1979], §06.3) | |
| A reaction: I read the generalisation as 'If A can be either a premise or a conclusion, you can bypass it'. The first version is just transitivity (which by-passes the middle step). |
| 13835 | Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking] |
| Full Idea: Only the cut rule can have a conclusion that is less complex than its premises. Hence when cut is not used, a derivation is quite literally constructive, building up from components. Any theorem obtained by cut can be obtained without it. | |
| From: Ian Hacking (What is Logic? [1979], §08) |
| 13845 | The various logics are abstractions made from terms like 'if...then' in English [Hacking] |
| Full Idea: I don't believe English is by nature classical or intuitionistic etc. These are abstractions made by logicians. Logicians attend to numerous different objects that might be served by 'If...then', like material conditional, strict or relevant implication. | |
| From: Ian Hacking (What is Logic? [1979], §15) | |
| A reaction: The idea that they are 'abstractions' is close to my heart. Abstractions from what? Surely 'if...then' has a standard character when employed in normal conversation? |
| 13840 | First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking] |
| Full Idea: First-order logic is the strongest complete compact theory with a Löwenheim-Skolem theorem. | |
| From: Ian Hacking (What is Logic? [1979], §13) |
| 13844 | A limitation of first-order logic is that it cannot handle branching quantifiers [Hacking] |
| Full Idea: Henkin proved that there is no first-order treatment of branching quantifiers, which do not seem to involve any idea that is fundamentally different from ordinary quantification. | |
| From: Ian Hacking (What is Logic? [1979], §13) | |
| A reaction: See Hacking for an example of branching quantifiers. Hacking is impressed by this as a real limitation of the first-order logic which he generally favours. |
| 13842 | Second-order completeness seems to need intensional entities and possible worlds [Hacking] |
| Full Idea: Second-order logic has no chance of a completeness theorem unless one ventures into intensional entities and possible worlds. | |
| From: Ian Hacking (What is Logic? [1979], §13) |
| 13837 | With a pure notion of truth and consequence, the meanings of connectives are fixed syntactically [Hacking] |
| Full Idea: My doctrine is that the peculiarity of the logical constants resides precisely in that given a certain pure notion of truth and consequence, all the desirable semantic properties of the constants are determined by their syntactic properties. | |
| From: Ian Hacking (What is Logic? [1979], §09) | |
| A reaction: He opposes this to Peacocke 1976, who claims that the logical connectives are essentially semantic in character, concerned with the preservation of truth. |
| 13839 | Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking] |
| Full Idea: For some purposes the variables of first-order logic can be regarded as prepositions and place-holders that could in principle be dispensed with, say by a system of arrows indicating what places fall in the scope of which quantifier. | |
| From: Ian Hacking (What is Logic? [1979], §11) | |
| A reaction: I tend to think of variables as either pronouns, or as definite descriptions, or as temporary names, but not as prepositions. Must address this new idea... |
| 13843 | If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking] |
| Full Idea: A Löwenheim-Skolem theorem holds for anything which, on my delineation, is a logic. | |
| From: Ian Hacking (What is Logic? [1979], §13) | |
| A reaction: I take this to be an unusually conservative view. Shapiro is the chap who can give you an alternative view of these things, or Boolos. |
| 23743 | Capturing all the common sense facts about rationality is almost impossible [Smith,M] |
| Full Idea: It would be a superhuman task just to write down an explicit, non-summary style, statement of the platitudes that capture our idea of what it is to be fully rational. | |
| From: Michael Smith (The Moral Problem [1994], 5.9) | |
| A reaction: Well said. Philosophers are inclined to make simplistic binary judgements about whether persons or animals are rational. A visit to YouTube will show fish acting extremely rationally. |
| 18265 | We don't judge by combining subject and concept; we get a concept by splitting up a judgement [Frege] |
| Full Idea: Instead of putting a judgement together out of an individual as subject and an already previously formed concept as predicate, we do the opposite and arrive at a concept by splitting up the content of possible judgement. | |
| From: Gottlob Frege (Boole calculus and the Concept script [1881], p.17) | |
| A reaction: This is behind holistic views of sentences, and hence of whole languages, and behind Quine's rejection of 'properties' inferred from the predicates in judgements. |
| 23724 | A pure desire could be criticised if it were based on a false belief [Smith,M] |
| Full Idea: There is a minor proviso to Hume's view, which is that desires are subject to rational criticism, but only insofar as they are based on beliefs that are subject to rational criticism. | |
| From: Michael Smith (The Moral Problem [1994], 1.3) | |
| A reaction: He says this is not a refutation of the basic Humean claim. He has in mind a desire such as to consume cyanide because you believe it will be good for you. |
| 23736 | A person can have a desire without feeling it [Smith,M] |
| Full Idea: We should concede that a desire may be had in the absence of its being felt. | |
| From: Michael Smith (The Moral Problem [1994], 4.5) | |
| A reaction: A nice observation. An example he gives is a father's desire that his child does well. Smith is discussing Hume's account of motivation in terms of desires and beliefs. |
| 23723 | In the Humean account, desires are not true/false, or subject to any rational criticism [Smith,M] |
| Full Idea: According to the standard picture of human psychology that we get from Hume, not only are desires not assessable in terms of truth and falsehood, they are not subject to any sort of rational criticism at all. | |
| From: Michael Smith (The Moral Problem [1994], 1.3) | |
| A reaction: This is where action theory meets metaethics. The separation of facts from values underlies this, because a desire is a fact, but the wickedness of a desire is not. Surely a desire could be a failure of practical reason? |
| 23735 | Subjects may be fallible about the desires which explain their actions [Smith,M] |
| Full Idea: It is an adequacy constraint on any conception of desire that the epistemology of desire it recommends allows that subjects may be fallible about the desires they have. | |
| From: Michael Smith (The Moral Problem [1994], 4.5) | |
| A reaction: [I do wish authors would write my short versions instead of their rambling sentences!] Even after the event we may be unsure why we did something. If someone observes self-interest when I thought my action was altruistic, I don't know how to respond. |
| 23738 | Humeans (unlike their opponents) say that desires and judgements can separate [Smith,M] |
| Full Idea: Humeans claim that agents who believe they should act may nevertheless lack the desire to do so, where anti-Humeans must say the two go together, and someone with the belief thereby has the desire. | |
| From: Michael Smith (The Moral Problem [1994], 4.7) | |
| A reaction: [very compressed] A very helpful distinction about the classic debates over the motivations of action. Smith defends the Humean view, and makes it very plausible. No mere sense of rightness or duty can compel us to act. |
| 23742 | If first- and second-order desires conflict, harmony does not require the second-order to win [Smith,M] |
| Full Idea: Even if we assume that reason prefers harmony between first- and second-order desires, there is no reason to assume that reason is on the side of achieving that harmony by changing first-order desires to suit second-order, rather than vice versa. | |
| From: Michael Smith (The Moral Problem [1994], 5.7) | |
| A reaction: [Smith is discussing David Lewis 1989 on second-order desires] Smith says that on the Humean view the rational winner should simply be the stronger of the two. Since this sounds like an endorsement for weakness of will, Smith relies on beliefs. |
| 23746 | Objective reasons to act might be the systematic desires of a fully rational person [Smith,M] |
| Full Idea: One way to decide what we have normative reasons to do …is by trying to find a set of desires that is systematically justifiable, which is our best assessment of the desires we would have under conditions of full rationality. | |
| From: Michael Smith (The Moral Problem [1994], 5.9) | |
| A reaction: This is Smith accepting the Humean view that desires are essential for motivation, but trying to find a marriage of desires with reason to produce the more objective aspects of morality. An interesting aspiration… |
| 23739 | Goals need desires, and so only desires can motivate us [Smith,M] |
| Full Idea: Only an agent's desires may constitute her having certain goals, and it follows from this that only her desires may constitute her motivating reasons. | |
| From: Michael Smith (The Moral Problem [1994], 4.8) | |
| A reaction: We might distinguish between reasons which direct us towards certain ends, and reasons which motivate us to pursue those ends. Most mornings I have a reason to get out of bed, which precedes my motivation to actually do it. |
| 23733 | Motivating reasons are psychological, while normative reasons are external [Smith,M] |
| Full Idea: There are motivating reasons for action, which are psychological states, and normative reasons, which are propositions of the general form 'a person's doing this is desirable or required'. | |
| From: Michael Smith (The Moral Problem [1994], 4.2) | |
| A reaction: Motivating reasons are locatable entities in minds, whereas normative reasons are either abstract, or perhaps motivating reasons expressed by other people. Smith says the two types are unconnected. |
| 23740 | Humeans take maximising desire satisfaction as the normative reasons for actions [Smith,M] |
| Full Idea: The distinctive Humean view of normative reasons for action is that the rational thing for an agent to do is simply to act so as to maximally satisfy her desires, whatever the content of those desires. | |
| From: Michael Smith (The Moral Problem [1994], 5.1) | |
| A reaction: Smith disagrees with this view (though he agrees with Hume about motivating reasons). An obvious problem for the Humean view would be a strong desire to do something excessively dangerous. |
| 23745 | We cannot expect even fully rational people to converge on having the same desires for action [Smith,M] |
| Full Idea: We cannot expect that, even under conditions of full rationality, agents would all converge on the same desires about what is to be done in the various circumstances they might face. | |
| From: Michael Smith (The Moral Problem [1994], 5.9) | |
| A reaction: A very good argument in favour of the Humean view that desires are an essential part of moral motivation. Possible convergence of view is a standard hallmark of communal rationality. |
| 23731 | 'Externalists' say moral judgements are not reasons, and maybe not even motives [Smith,M] |
| Full Idea: The 'externalist' view of morality says either that judgements of rightness are motives but not reasons, or (more strongly) that they are neither, meaning that moral judgements do not have practical implications. | |
| From: Michael Smith (The Moral Problem [1994], 3.1) | |
| A reaction: [Philippa Foot's untypical 1972 article is cited for the strong view. Hare and Blackburn are typical of the first view]. I would say that such judgements are both reasons and motives - but not necessarily for me! 'Someone should do something about this!'. |
| 23732 | A person could make a moral judgement without being in any way motivated by it [Smith,M] |
| Full Idea: Amoralists make moral judgements without being motivated accordingly, and without suffering any sort of practical irrationality either; the practicality requirement of moral judgement is thus false. | |
| From: Michael Smith (The Moral Problem [1994], 3.3) | |
| A reaction: It is hard to imagine an immoralist with this nihilistic attitude bothering to make any moral judgements at all. Why would someone indifferent to art make aesthetic judgements? What could a 'judgement of rightness' mean to an amoralist? |
| 23729 | Moral internalism says a judgement of rightness is thereby motivating [Smith,M] |
| Full Idea: Moral 'internalism' says if an agent judges an action as right in some circumstance, then they are either thereby motivated to do it, or they are irrational (e.g. their will is weak). | |
| From: Michael Smith (The Moral Problem [1994], 3.1) | |
| A reaction: [Somewhat reworded] So the motivation comes from an internal judgement, not from external factors. Is it not tautological that 'this is the right thing to do' means it should be done (ceteris paribus)? |
| 23730 | 'Rationalism' says the rightness of an action is a reason to perform it [Smith,M] |
| Full Idea: Moral 'rationalism' says if an action is right for agents in some circumstances, then there is a reason for the agents to do it. | |
| From: Michael Smith (The Moral Problem [1994], 3.1) | |
| A reaction: That is, there is not merely a motivation to act (the 'internalist' view), but there is a reason to act. Smith calls both views the 'practicality requirement' of normal moral judgements. Smith defends the rationalist view. |
| 23727 | Expressivists count attitudes as 'moral' if they concern features of things, rather than their mere existence [Smith,M] |
| Full Idea: The pro- and con- attitudes of the expressivists count as 'moral' only if they are had towards particular people, actions or states of affairs in virtue of their natural features, ….rather than in virtue of being the particulars that they are. | |
| From: Michael Smith (The Moral Problem [1994], 2.4) | |
| A reaction: So whereas emotivists don't have to have any reasons for their moral feelings, other expressivists seem to require reasons (i.e. indicating features of things) to endorse their attitudes. What of reasonless emotionless attitudes? |
| 23741 | Is valuing something a matter of believing or a matter of desiring? [Smith,M] |
| Full Idea: What is it to value something? That is, equivalently, what is it to accept that we have a normative reason to do something? In Hume's terms, is it a matter of believing? Or is it a matter of desiring? We seem to face a dilemma. | |
| From: Michael Smith (The Moral Problem [1994], 5.4) | |
| A reaction: Smith is discussing moral motivation, and there is obviously more to valuing something than acting on it. Nice question, though. Personally I value St Paul's Cathedral, but I don't desire it. I value heart surgeons, but don't want to emulate them. |