32 ideas
10676 | The Axiom of Choice is a non-logical principle of set-theory [Hossack] |
Full Idea: The Axiom of Choice seems better treated as a non-logical principle of set-theory. | |
From: Keith Hossack (Plurals and Complexes [2000], 4 n8) | |
A reaction: This reinforces the idea that set theory is not part of logic (and so pure logicism had better not depend on set theory). |
10686 | The Axiom of Choice guarantees a one-one correspondence from sets to ordinals [Hossack] |
Full Idea: We cannot explicitly define one-one correspondence from the sets to the ordinals (because there is no explicit well-ordering of R). Nevertheless, the Axiom of Choice guarantees that a one-one correspondence does exist, even if we cannot define it. | |
From: Keith Hossack (Plurals and Complexes [2000], 10) |
10687 | Maybe we reduce sets to ordinals, rather than the other way round [Hossack] |
Full Idea: We might reduce sets to ordinal numbers, thereby reversing the standard set-theoretical reduction of ordinals to sets. | |
From: Keith Hossack (Plurals and Complexes [2000], 10) | |
A reaction: He has demonstrated that there are as many ordinals as there are sets. |
10677 | Extensional mereology needs two definitions and two axioms [Hossack] |
Full Idea: Extensional mereology defs: 'distinct' things have no parts in common; a 'fusion' has some things all of which are parts, with no further parts. Axioms: (transitivity) a part of a part is part of the whole; (sums) any things have a unique fusion. | |
From: Keith Hossack (Plurals and Complexes [2000], 5) |
10671 | Plural definite descriptions pick out the largest class of things that fit the description [Hossack] |
Full Idea: If we extend the power of language with plural definite descriptions, these would pick out the largest class of things that fit the description. | |
From: Keith Hossack (Plurals and Complexes [2000], 3) |
10666 | Plural reference will refer to complex facts without postulating complex things [Hossack] |
Full Idea: It may be that plural reference gives atomism the resources to state complex facts without needing to refer to complex things. | |
From: Keith Hossack (Plurals and Complexes [2000], 1) | |
A reaction: This seems the most interesting metaphysical implication of the possibility of plural quantification. |
10669 | Plural reference is just an abbreviation when properties are distributive, but not otherwise [Hossack] |
Full Idea: If all properties are distributive, plural reference is just a handy abbreviation to avoid repetition (as in 'A and B are hungry', to avoid 'A is hungry and B is hungry'), but not all properties are distributive (as in 'some people surround a table'). | |
From: Keith Hossack (Plurals and Complexes [2000], 2) | |
A reaction: The characteristic examples to support plural quantification involve collective activity and relations, which might be weeded out of our basic ontology, thus leaving singular quantification as sufficient. |
10675 | A plural comprehension principle says there are some things one of which meets some condition [Hossack] |
Full Idea: Singular comprehension principles have a bad reputation, but the plural comprehension principle says that given a condition on individuals, there are some things such that something is one of them iff it meets the condition. | |
From: Keith Hossack (Plurals and Complexes [2000], 4) |
10673 | Plural language can discuss without inconsistency things that are not members of themselves [Hossack] |
Full Idea: In a plural language we can discuss without fear of inconsistency the things that are not members of themselves. | |
From: Keith Hossack (Plurals and Complexes [2000], 4) | |
A reaction: [see Hossack for details] |
10680 | The theory of the transfinite needs the ordinal numbers [Hossack] |
Full Idea: The theory of the transfinite needs the ordinal numbers. | |
From: Keith Hossack (Plurals and Complexes [2000], 8) |
10684 | I take the real numbers to be just lengths [Hossack] |
Full Idea: I take the real numbers to be just lengths. | |
From: Keith Hossack (Plurals and Complexes [2000], 9) | |
A reaction: I love it. Real numbers are beginning to get on my nerves. They turn up to the party with no invitation and improperly dressed, and then refuse to give their names when challenged. |
10674 | A plural language gives a single comprehensive induction axiom for arithmetic [Hossack] |
Full Idea: A language with plurals is better for arithmetic. Instead of a first-order fragment expressible by an induction schema, we have the complete truth with a plural induction axiom, beginning 'If there are some numbers...'. | |
From: Keith Hossack (Plurals and Complexes [2000], 4) |
10681 | In arithmetic singularists need sets as the instantiator of numeric properties [Hossack] |
Full Idea: In arithmetic singularists need sets as the instantiator of numeric properties. | |
From: Keith Hossack (Plurals and Complexes [2000], 8) |
10685 | Set theory is the science of infinity [Hossack] |
Full Idea: Set theory is the science of infinity. | |
From: Keith Hossack (Plurals and Complexes [2000], 10) |
10668 | We are committed to a 'group' of children, if they are sitting in a circle [Hossack] |
Full Idea: By Quine's test of ontological commitment, if some children are sitting in a circle, no individual child can sit in a circle, so a singular paraphrase will have us committed to a 'group' of children. | |
From: Keith Hossack (Plurals and Complexes [2000], 2) | |
A reaction: Nice of why Quine is committed to the existence of sets. Hossack offers plural quantification as a way of avoiding commitment to sets. But is 'sitting in a circle' a real property (in the Shoemaker sense)? I can sit in a circle without realising it. |
10664 | Complex particulars are either masses, or composites, or sets [Hossack] |
Full Idea: Complex particulars are of at least three types: masses (which sum, of which we do not ask 'how many?' but 'how much?'); composite individuals (how many?, and summing usually fails); and sets (only divisible one way, unlike composites). | |
From: Keith Hossack (Plurals and Complexes [2000], 1) | |
A reaction: A composite pile of grains of sand gradually becomes a mass, and drops of water become 'water everywhere'. A set of people divides into individual humans, but redescribe the elements as the union of males and females? |
10678 | The relation of composition is indispensable to the part-whole relation for individuals [Hossack] |
Full Idea: The relation of composition seems to be indispensable in a correct account of the part-whole relation for individuals. | |
From: Keith Hossack (Plurals and Complexes [2000], 7) | |
A reaction: This is the culmination of a critical discussion of mereology and ontological atomism. At first blush it doesn't look as if 'composition' has much chance of being a precise notion, and it will be plagued with vagueness. |
10665 | Leibniz's Law argues against atomism - water is wet, unlike water molecules [Hossack] |
Full Idea: We can employ Leibniz's Law against mereological atomism. Water is wet, but no water molecule is wet. The set of infinite numbers is infinite, but no finite number is infinite. ..But with plural reference the atomist can resist this argument. | |
From: Keith Hossack (Plurals and Complexes [2000], 1) | |
A reaction: The idea of plural reference is to state plural facts without referring to complex things, which is interesting. The general idea is that we have atomism, and then all the relations, unities, identities etc. are in the facts, not in the things. I like it. |
10682 | The fusion of five rectangles can decompose into more than five parts that are rectangles [Hossack] |
Full Idea: The fusion of five rectangles may have a decomposition into more than five parts that are rectangles. | |
From: Keith Hossack (Plurals and Complexes [2000], 8) |
10663 | A thought can refer to many things, but only predicate a universal and affirm a state of affairs [Hossack] |
Full Idea: A thought can refer to a particular or a universal or a state of affairs, but it can predicate only a universal and it can affirm only a state of affairs. | |
From: Keith Hossack (Plurals and Complexes [2000], 1) | |
A reaction: Hossack is summarising Armstrong's view, which he is accepting. To me, 'thought' must allow for animals, unlike language. I think Hossack's picture is much too clear-cut. Do animals grasp universals? Doubtful. Can they predicate? Yes. |
2705 | How can intuitionists distinguish universal convictions from local cultural ones? [Hare] |
Full Idea: There are convictions which are common to most societies; but there are others which are not, and no way is given by intuitionists of telling which are the authoritative data. | |
From: Richard M. Hare (Universal Prescriptivism [1991], p.454) | |
A reaction: It seems unfair on intuitionists to say they haven't given a way to evaluate such things, given that they have offered intuition. The issue is what exactly they mean by 'intuition'. |
2712 | You can't use intuitions to decide which intuitions you should cultivate [Hare] |
Full Idea: If it comes to deciding what intuitions and dispositions to cultivate, we cannot rely on the intuitions themselves, as intuitionists do. | |
From: Richard M. Hare (Universal Prescriptivism [1991], p.461) | |
A reaction: Makes intuitionists sound a bit dim. Surely Hume identifies dispositions (such as benevolence) which should be cultivated, because they self-evidently improve social life? |
2706 | Emotivists mistakenly think all disagreements are about facts, and so there are no moral reasons [Hare] |
Full Idea: Emotivists concluded too hastily that because naturalism and intuitionism are false, you cannot reason about moral questions, because they assumed that the only questions you can reason about are factual ones. | |
From: Richard M. Hare (Universal Prescriptivism [1991], p.455) | |
A reaction: Personally I have a naturalistic view of ethics (based on successful functioning, as indicated by Aristotle), so not my prob. Why can't we reason about expressive emotions? We reason about art. |
2709 | Prescriptivism sees 'ought' statements as imperatives which are universalisable [Hare] |
Full Idea: Universal prescriptivists hold that 'ought'-judgements are prescriptive like plain imperatives, but differ from them in being universalisable. | |
From: Richard M. Hare (Universal Prescriptivism [1991], p.457) | |
A reaction: Sounds a bit tautological. Which comes first, the normativity or the universalisability? |
2704 | If morality is just a natural or intuitive description, that leads to relativism [Hare] |
Full Idea: Non-descriptivists (e.g. prescriptivists) reject descriptivism in its naturalist or intuitionist form, because they are both destined to collapse into relativism. | |
From: Richard M. Hare (Universal Prescriptivism [1991], p.453) | |
A reaction: I'm not clear from this why prescriptism would not also turn out to be relativist, if it includes evaluations along with facts. |
2703 | Descriptivism say ethical meaning is just truth-conditions; prescriptivism adds an evaluation [Hare] |
Full Idea: Ethical descriptivism is the view that ethical sentence-meaning is wholly determined by truth-conditions. …Prescriptivists think there is a further element of meaning, which expresses prescriptions or evaluations or attitudes which we assent to. | |
From: Richard M. Hare (Universal Prescriptivism [1991], p.452) | |
A reaction: Not sure I understand either of these. If all meaning consists of truth-conditions, that will apply to ethics. If meaning includes evaluations, that will apply to non-ethics. |
2707 | If there can be contradictory prescriptions, then reasoning must be involved [Hare] |
Full Idea: Prescriptivists claim that there are rules of reasoning which govern non-descriptive as well as descriptive speech acts. The standard example is possible logical inconsistency between contradictory prescriptions. | |
From: Richard M. Hare (Universal Prescriptivism [1991], p.455) | |
A reaction: The example doesn't seem very good. Inconsistency can appear in any area of thought, but that isn't enough to infer full 'rules of reasoning'. I could desire two incompatible crazy things. |
2708 | An 'ought' statement implies universal application [Hare] |
Full Idea: In any 'ought' statement there is implicit a principle which says that the statement applies to all precisely similar situations. | |
From: Richard M. Hare (Universal Prescriptivism [1991], p.456) | |
A reaction: No two situations can ever be 'precisely' similar. Indeed, 'precisely similar' may be an oxymoron (at least for situations). Kantians presumably like this idea. |
2711 | Prescriptivism implies a commitment, but descriptivism doesn't [Hare] |
Full Idea: Prescriptivists hold that moral judgements commit the speaker to motivations and actions, but non-moral facts by themselves do not do this. | |
From: Richard M. Hare (Universal Prescriptivism [1991], p.459) | |
A reaction: Surely hunger motivates to action? I suppose the key word is 'commit'. But lazy people are allowed to make moral judgements. |
2710 | Moral judgements must invoke some sort of principle [Hare] |
Full Idea: To make moral judgements is implicitly to invoke some principle, however specific. | |
From: Richard M. Hare (Universal Prescriptivism [1991], p.458) |
21096 | The only purpose of government is to administer justice, which brings security [Hume] |
Full Idea: Man is engaged to establish political society in order to administer justice, without which there could be no peace among them, nor safety, nor mutual intercourse. ...Government has no other purpose but the distribution of justice. | |
From: David Hume (Of the Origin of Government [1750], p.28) | |
A reaction: The need for a society in order to ensure mutual intercourse sounds like Hobbes, and a pessimism about trust. By 'justice' he means the administration of law. |
10683 | We could ignore space, and just talk of the shape of matter [Hossack] |
Full Idea: We might dispense with substantival space, and say that if the distribution of matter in space could have been different, that just means the matter of the Universe could have been shaped differently (with geometry as the science of shapes). | |
From: Keith Hossack (Plurals and Complexes [2000], 9) |