35 ideas
| 2666 | Carneades' pinnacles of philosophy are the basis of knowledge (the criterion of truth) and the end of appetite (good) [Carneades, by Cicero] |
| Full Idea: Carneades said the two greatest things in philosophy were the criterion of truth and the end of goods, and no man could be a sage who was ignorant of the existence of either a beginning of the process of knowledge or an end of appetition. | |
| From: report of Carneades (fragments/reports [c.174 BCE]) by M. Tullius Cicero - Academica II.09.29 | |
| A reaction: Nice, but I would want to emphasise the distinction between truth and its criterion. Admittedly we would have no truth without a good criterion, but the truth itself should be held in higher esteem than our miserable human means of grasping it. |
| 21390 | Future events are true if one day we will say 'this event is happening now' [Carneades] |
| Full Idea: We call those past events true of which at an earlier time this proposition was true: 'They are present now'; similarly, we shall call those future events true of which at some future time this proposition will be true: 'They are present now'. | |
| From: Carneades (fragments/reports [c.174 BCE]), quoted by M. Tullius Cicero - On Fate ('De fato') 9.23-8 | |
| A reaction: This is a very nice way of paraphrasing statements about the necessity of true future contingent events. It still relies, of course, on the veracity of a tensed assertion |
| 21672 | We say future things are true that will possess actuality at some following time [Carneades, by Cicero] |
| Full Idea: Just as we speak of past things as true that possessed true actuality at some former time, so we speak of future things as true that will possess true actuality at some following time. | |
| From: report of Carneades (fragments/reports [c.174 BCE]) by M. Tullius Cicero - On Fate ('De fato') 11.27 | |
| A reaction: This ducks the Aristotle problem of where it is true NOW when you say there will be a sea-fight tomorrow, and it turns out to be true. Carneades seems to be affirming a truth when it does not yet have a truthmaker. |
| 14240 | The empty set is something, not nothing! [Oliver/Smiley] |
| Full Idea: Some authors need to be told loud and clear: if there is an empty set, it is something, not nothing. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 1.2) | |
| A reaction: I'm inclined to think of a null set as a pair of brackets, so maybe that puts it into a metalanguage. |
| 14239 | The empty set is usually derived from Separation, but it also seems to need Infinity [Oliver/Smiley] |
| Full Idea: The empty set is usually derived via Zermelo's axiom of separation. But the axiom of separation is conditional: it requires the existence of a set in order to generate others as subsets of it. The original set has to come from the axiom of infinity. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 1.2) | |
| A reaction: They charge that this leads to circularity, as Infinity depends on the empty set. |
| 14241 | We don't need the empty set to express non-existence, as there are other ways to do that [Oliver/Smiley] |
| Full Idea: The empty set is said to be useful to express non-existence, but saying 'there are no Us', or ¬∃xUx are no less concise, and certainly less roundabout. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 1.2) |
| 14242 | Maybe we can treat the empty set symbol as just meaning an empty term [Oliver/Smiley] |
| Full Idea: Suppose we introduce Ω not as a term standing for a supposed empty set, but as a paradigm of an empty term, not standing for anything. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 1.2) | |
| A reaction: This proposal, which they go on to explore, seems to mean that Ω (i.e. the traditional empty set symbol) is no longer part of set theory but is part of semantics. |
| 14243 | The unit set may be needed to express intersections that leave a single member [Oliver/Smiley] |
| Full Idea: Thomason says with no unit sets we couldn't call {1,2}∩{2,3} a set - but so what? Why shouldn't the intersection be the number 2? However, we then have to distinguish three different cases of intersection (common subset or member, or disjoint). | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 2.2) |
| 14234 | If you only refer to objects one at a time, you need sets in order to refer to a plurality [Oliver/Smiley] |
| Full Idea: A 'singularist', who refers to objects one at a time, must resort to the language of sets in order to replace plural reference to members ('Henry VIII's wives') by singular reference to a set ('the set of Henry VIII's wives'). | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], Intro) | |
| A reaction: A simple and illuminating point about the motivation for plural reference. Null sets and singletons give me the creeps, so I would personally prefer to avoid set theory when dealing with ontology. |
| 14237 | We can use plural language to refer to the set theory domain, to avoid calling it a 'set' [Oliver/Smiley] |
| Full Idea: Plurals earn their keep in set theory, to answer Skolem's remark that 'in order to treat of 'sets', we must begin with 'domains' that are constituted in a certain way'. We can speak in the plural of 'the objects', not a 'domain' of objects. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], Intro) | |
| A reaction: [Skolem 1922:291 in van Heijenoort] Zermelo has said that the domain cannot be a set, because every set belongs to it. |
| 14245 | Logical truths are true no matter what exists - but predicate calculus insists that something exists [Oliver/Smiley] |
| Full Idea: Logical truths should be true no matter what exists, so true even if nothing exists. The classical predicate calculus, however, makes it logically true that something exists. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 5.1) |
| 14246 | If mathematics purely concerned mathematical objects, there would be no applied mathematics [Oliver/Smiley] |
| Full Idea: If mathematics was purely concerned with mathematical objects, there would be no room for applied mathematics. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 5.1) | |
| A reaction: Love it! Of course, they are using 'objects' in the rather Fregean sense of genuine abstract entities. I don't see why fictionalism shouldn't allow maths to be wholly 'pure', although we have invented fictions which actually have application. |
| 14247 | Sets might either represent the numbers, or be the numbers, or replace the numbers [Oliver/Smiley] |
| Full Idea: Identifying numbers with sets may mean one of three quite different things: 1) the sets represent the numbers, or ii) they are the numbers, or iii) they replace the numbers. | |
| From: Oliver,A/Smiley,T (What are Sets and What are they For? [2006], 5.2) | |
| A reaction: Option one sounds the most plausible to me. I will take numbers to be patterns embedded in nature, and sets are one way of presenting them in shorthand form, in order to bring out what is repeated. |
| 15825 | Carneades denied the transitivity of identity [Carneades, by Chisholm] |
| Full Idea: Carneades denied the principle of the transitivity of identity. | |
| From: report of Carneades (fragments/reports [c.174 BCE], fr 41-42) by Roderick Chisholm - Person and Object 3.1 | |
| A reaction: Chisholm calls this 'extreme', but I assume Carneades wouldn't deny the principle in mathematics. I'm guessing that he just means that nothing ever stays quite the same. |
| 21389 | Carneades distinguished logical from causal necessity, when talking of future events [Long on Carneades] |
| Full Idea: From 'E will take place is true' it follows that E must take place. But 'must' here is logical not causal necessity. It is a considerable achievement of Carneades to have distinguished these two senses of necessity. | |
| From: comment on Carneades (fragments/reports [c.174 BCE]) by A.A. Long - Hellenistic Philosophy 3 | |
| A reaction: Personally I am inclined to think 'necessity' is univocal, and does not have two senses. What Carneades has nicely done is distinguish the two different grounds for the necessities. |
| 21671 | Voluntary motion is intrinsically within our power, and this power is its cause [Carneades, by Cicero] |
| Full Idea: Voluntary motion possesses the intrinsic property of being in our power and of obeying us, and its obedience is not uncaused, for its nature is itself the cause of this. | |
| From: report of Carneades (fragments/reports [c.174 BCE]) by M. Tullius Cicero - On Fate ('De fato') 11.25 | |
| A reaction: To say that actions arise from our 'intrinsic power' is not much of an explanation, but it is still informative - that you should study the intrinsic powers of humans if you want to explain it. |
| 21391 | Some actions are within our power; determinism needs prior causes for everything - so it is false [Carneades, by Cicero] |
| Full Idea: Now something is in our power; but if everything happens as a result of destiny all things happen as a result of antecedent causes; therefore what happens does not happen as a result of destiny. | |
| From: report of Carneades (fragments/reports [c.174 BCE]) by M. Tullius Cicero - On Fate ('De fato') 14.31 | |
| A reaction: This invites the question of whether some things really are 'in our power'. Carneades (as expressed by Cicero) takes that for granted. Our 'power' may be antecedent causes in disguise. |
| 21674 | Even Apollo can only foretell the future when it is naturally necessary [Carneades, by Cicero] |
| Full Idea: Carneades used to say that not even Apollo could tell any future events except those whose causes were so held together that they must necessarily happen. | |
| From: report of Carneades (fragments/reports [c.174 BCE]) by M. Tullius Cicero - On Fate ('De fato') 14.32 | |
| A reaction: Carneades is opposing the usual belief in divination, where even priests can foretell contingent future events to some extent. Careneades, of course, was defending free will. |
| 20014 | Actions include: the involuntary, the purposeful, the intentional, and the self-consciously autonomous [Wilson/Schpall] |
| Full Idea: There are different levels of action, including at least: unconscious and/or involuntary behaviour, purposeful or goal-directed activity, intentional action, and the autonomous acts or actions of self-consciously active human agents. | |
| From: Wilson,G/Schpall,S (Action [2012], 1) | |
| A reaction: The fourth class is obviously designed to distinguish us from the other animals. It immediately strikes me as very optimistic to distinguish four (at least) clear categories, but you have to start somewhere. |
| 20019 | Maybe bodily movements are not actions, but only part of an agent's action of moving [Wilson/Schpall] |
| Full Idea: Some say that the movement's of agent's body are never actions. It is only the agent's direct moving of, say, his leg that constitutes a physical action; the leg movement is merely caused by and/or incorporated as part of the act of moving. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.2) | |
| A reaction: [they cite Jennifer Hornsby 1980] It seems normal to deny a twitch the accolade of an 'action', so I suppose that is right. Does the continual movement of my tongue count as action? Only if I bring it under control? Does it matter? Only in forensics. |
| 20021 | Is the action the arm movement, the whole causal process, or just the trying to do it? [Wilson/Schpall] |
| Full Idea: Some philosophers have favored the overt arm movement the agent performs, some favor the extended causal process he initiates, and some prefer the relevant event of trying that precedes and 'generates' the rest. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.2) | |
| A reaction: [Davidson argues for the second, Hornsby for the third] There seems no way to settle this, and a compromise looks best. Mere movement won't do, and mere trying won't do, and whole processes get out of control. |
| 20022 | To be intentional, an action must succeed in the manner in which it was planned [Wilson/Schpall] |
| Full Idea: If someone fires a bullet to kill someone, misses, and dislodges hornets that sting him to death, this implies that an intentional action must include succeeding in a manner according to the original plan. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: [their example, compressed] This resembles Gettier's problem cases for knowledge. If the shooter deliberately and maliciously brought down the hornet's nest, that would be intentional murder. Sounds right. |
| 20023 | If someone believes they can control the lottery, and then wins, the relevant skill is missing [Wilson/Schpall] |
| Full Idea: If someone enters the lottery with the bizarre belief that they can control who wins, and then wins it, that suggest that intentional actions must not depend on sheer luck, but needs competent exercise of the relevant skill. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: A nice companion to Idea 20022, which show that a mere intention is not sufficient to motivate and explain an action. |
| 20025 | We might intend two ways to acting, knowing only one of them can succeed [Wilson/Schpall] |
| Full Idea: If an agent tries to do something by two different means, only one of which can succeed, then the behaviour is rational, even though one of them is an attempt to do an action which cannot succeed. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: [a concise account of a laborious account of an example from Bratman 1984, 1987] Bratman uses this to challenge the 'Simple View', that intention leads straightforwardly to action. |
| 20031 | On one model, an intention is belief-desire states, and intentional actions relate to beliefs and desires [Wilson/Schpall] |
| Full Idea: On the simple desire-belief model, an intention is a combination of desire-belief states, and an action is intentional in virtue of standing in the appropriate relation to these simpler terms. | |
| From: Wilson,G/Schpall,S (Action [2012], 4) | |
| A reaction: This is the traditional view found in Hume, and is probably endemic to folk psychology. They cite Bratman 1987 as the main opponent of the view. |
| 20028 | Groups may act for reasons held by none of the members, so maybe groups are agents [Wilson/Schpall] |
| Full Idea: Rational group action may involve a 'collectivising of reasons', with participants acting in ways that are not rationally recommended from the individual viewpoint. This suggests that groups can be rational, intentional agents. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: [Pettit 2003] is the source for this. Gilbert says individuals can have joint commitment; Pettit says the group can be an independent agent. The matter of shared intentions is interesting, but there is no need for the ontology to go berserk. |
| 20027 | If there are shared obligations and intentions, we may need a primitive notion of 'joint commitment' [Wilson/Schpall] |
| Full Idea: An account of mutual obligation to do something may require that we give up reductive individualist accounts of shared activity and posit a primitive notion of 'joint commitment'. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: [attributed to Margaret Gilbert 2000] If 'we' are trying to do something, that seems to give an externalist picture of intentions, rather like all the other externalisms floating around these days. I don't buy any of it, me. |
| 20016 | Strong Cognitivism identifies an intention to act with a belief [Wilson/Schpall] |
| Full Idea: A Strong Cognitivist is someone who identifies an intention with a certain pertinent belief about what she is doing or about to do. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.1) | |
| A reaction: (Sarah Paul 2009 makes this distinction) The belief, if so, seems to be as much counterfactual as factual. Hope seems to come into it, which isn't exactly a belief. |
| 20017 | Weak Cognitivism says intentions are only partly constituted by a belief [Wilson/Schpall] |
| Full Idea: A Weak Cognitivist holds that intentions are partly constituted by, but are not identical with, relevant beliefs about the action. Grice (1971) said an intention is willing an action, combined with a belief that this will lead to the action. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.1) | |
| A reaction: [compressed] I didn't find Strong Cognitivism appealing, but it seems hard to argue with some form of the weak version. |
| 20018 | Strong Cognitivism implies a mode of 'practical' knowledge, not based on observation [Wilson/Schpall] |
| Full Idea: Strong Cognitivists say intentions/beliefs are not based on observation or evidence, and are causally reliable in leading to appropriate actions, so this is a mode of 'practical' knowledge that has not been derived from observation. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.1) | |
| A reaction: [compressed - Stanford unnecessarily verbose!] I see no mention in this discussion of 'hoping' that your action will turn out OK. We are usually right to hope, but it would be foolish to say that when we reach for the salt we know we won't knock it over. |
| 20012 | Maybe the explanation of an action is in the reasons that make it intelligible to the agent [Wilson/Schpall] |
| Full Idea: Some have maintained that we explain why an agent acted as he did when we explicate how the agent's normative reasons rendered the action intelligible in his eyes. | |
| From: Wilson,G/Schpall,S (Action [2012], Intro) | |
| A reaction: Modern psychology is moving against this, by showing how hidden biases can predominate over conscious reasons (as in Kahnemann's work). I would say this mode of explanation works better for highly educated people (but you can chuckle at that). |
| 20013 | It is generally assumed that reason explanations are causal [Wilson/Schpall] |
| Full Idea: The view that reason explanations are somehow causal explanations remains the dominant position. | |
| From: Wilson,G/Schpall,S (Action [2012], Intro) | |
| A reaction: I suspect that this is only because no philosopher has a better idea, and the whole issue is being slowly outflanked by psychology. |
| 20029 | Causalists allow purposive explanations, but then reduce the purpose to the action's cause [Wilson/Schpall] |
| Full Idea: Most causalists allow that reason explanations are teleological, but say that such purposive explanations are analysable causally, where the primary reasons for the act are the guiding causes of the act. | |
| From: Wilson,G/Schpall,S (Action [2012], 3) | |
| A reaction: The authors observe that it is hard to adjudicate on this matter, and that the concept of the 'cause' of an action is unclear. |
| 7398 | Carneades said that after a shipwreck a wise man would seize the only plank by force [Carneades, by Tuck] |
| Full Idea: Carneades argued forcefully that in the event of a shipwreck, the wise man would be prepared to seize the only plank capable of bearing him to shore, even if that meant pushing another person off it. | |
| From: report of Carneades (fragments/reports [c.174 BCE]) by Richard Tuck - Hobbes Ch.1 | |
| A reaction: [source for this?] This thought seems to have provoked great discussion in the sixteenth century (mostly sympathetic). I can't help thinking the right answer depends on assessing your rival. Die for a hero, drown a nasty fool. |
| 21392 | People change laws for advantage; either there is no justice, or it is a form of self-injury [Carneades, by Lactantius] |
| Full Idea: The same people often changed laws according to circumstances; there is no natural law. There is no such thing as justice or, if there is, it is the height of folly, since a man injures himself in taking thought for the advantage of others. | |
| From: report of Carneades (fragments/reports [c.174 BCE]) by Lactantius - Institutiones Divinae 5.16.4 | |
| A reaction: [An argument used by Carneades on his notorious 156BCE visit to Rome, where he argued both for and against justice] This is probably the right wing view of justice. Why give other people what they want, if it is at our expense? |