68 ideas
| 6405 | Moore's 'The Nature of Judgement' (1898) marked the rejection (with Russell) of idealism [Moore,GE, by Grayling] |
| Full Idea: The rejection of idealism by Moore and Russell was marked in 1898 by the publication of Moore's article 'The Nature of Judgement'. | |
| From: report of G.E. Moore (The Nature of Judgement [1899]) by A.C. Grayling - Russell Ch.2 | |
| A reaction: This now looks like a huge landmark in the history of British philosophy. |
| 17992 | The main aim of philosophy is to describe the whole Universe. [Moore,GE] |
| Full Idea: It seems to me that the most important and interesting thing which philosophers have tried to do ...is to give a general description of the whole of the Universe. | |
| From: G.E. Moore (Some Main Problems of Philosophy [1911], Ch. 1) | |
| A reaction: He adds that they aim to show what is in it, and what might be in it, and how the two relate. This sort of big view is the one I favour. I think the hallmark of philosophical thought is a high level of generality. He next proceeds to defend common sense. |
| 7527 | Analysis for Moore and Russell is carving up the world, not investigating language [Moore,GE, by Monk] |
| Full Idea: For Moore and Russell analysis is not - as is commonly understood now - a linguistic activity, but an ontological one. To analyse a proposition is not to investigate language, but to carve up the world so that it begins to make some sort of sense. | |
| From: report of G.E. Moore (The Nature of Judgement [1899]) by Ray Monk - Bertrand Russell: Spirit of Solitude Ch.4 | |
| A reaction: A thought dear to my heart. The twentieth century got horribly side-tracked into thinking that ontology was an entirely linguistic problem. I suggest that physicists analyse physical reality, and philosophers analyse abstract reality. |
| 9738 | Each line of a truth table is a model [Fitting/Mendelsohn] |
| Full Idea: Each line of a truth table is, in effect, a model. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.6) | |
| A reaction: I find this comment illuminating. It is being connected with the more complex models of modal logic. Each line of a truth table is a picture of how the world might be. |
| 9727 | Modal logic adds □ (necessarily) and ◊ (possibly) to classical logic [Fitting/Mendelsohn] |
| Full Idea: For modal logic we add to the syntax of classical logic two new unary operators □ (necessarily) and ◊ (possibly). | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.3) |
| 9726 | We let 'R' be the accessibility relation: xRy is read 'y is accessible from x' [Fitting/Mendelsohn] |
| Full Idea: We let 'R' be the accessibility relation: xRy is read 'y is accessible from x'. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.5) |
| 9737 | The symbol ||- is the 'forcing' relation; 'Γ ||- P' means that P is true in world Γ [Fitting/Mendelsohn] |
| Full Idea: The symbol ||- is used for the 'forcing' relation, as in 'Γ ||- P', which means that P is true in world Γ. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.6) |
| 13136 | The prefix σ names a possible world, and σ.n names a world accessible from that one [Fitting/Mendelsohn] |
| Full Idea: A 'prefix' is a finite sequence of positive integers. A 'prefixed formula' is an expression of the form σ X, where σ is a prefix and X is a formula. A prefix names a possible world, and σ.n names a world accessible from that one. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.2) |
| 13727 | A 'constant' domain is the same for all worlds; 'varying' domains can be entirely separate [Fitting/Mendelsohn] |
| Full Idea: In 'constant domain' semantics, the domain of each possible world is the same as every other; in 'varying domain' semantics, the domains need not coincide, or even overlap. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 4.5) |
| 9734 | Modern modal logic introduces 'accessibility', saying xRy means 'y is accessible from x' [Fitting/Mendelsohn] |
| Full Idea: Modern modal logic takes into consideration the way the modal relates the possible worlds, called the 'accessibility' relation. .. We let R be the accessibility relation, and xRy reads as 'y is accessible from x. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.5) | |
| A reaction: There are various types of accessibility, and these define the various modal logics. |
| 9736 | A 'model' is a frame plus specification of propositions true at worlds, written < G,R,||- > [Fitting/Mendelsohn] |
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Full Idea:
A 'model' is a frame plus a specification of which propositional letters are true at which worlds. It is written as |
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| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.6) |
| 9735 | A 'frame' is a set G of possible worlds, with an accessibility relation R, written < G,R > [Fitting/Mendelsohn] |
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Full Idea:
A 'frame' consists of a non-empty set G, whose members are generally called possible worlds, and a binary relation R, on G, generally called the accessibility relation. We say the frame is the pair |
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| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.6) |
| 9741 | Accessibility relations can be 'reflexive' (self-referring), 'transitive' (carries over), or 'symmetric' (mutual) [Fitting/Mendelsohn] |
| Full Idea: A relation R is 'reflexive' if every world is accessible from itself; 'transitive' if the first world is related to the third world (ΓRΔ and ΔRΩ → ΓRΩ); and 'symmetric' if the accessibility relation is mutual. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.7) | |
| A reaction: The different systems of modal logic largely depend on how these accessibility relations are specified. There is also the 'serial' relation, which just says that any world has another world accessible to it. |
| 13149 | S5: a) if n ◊X then kX b) if n ¬□X then k ¬X c) if n □X then k X d) if n ¬◊X then k ¬X [Fitting/Mendelsohn] |
| Full Idea: Simplified S5 rules: a) if n ◊X then kX b) if n ¬□X then k ¬X c) if n □X then k X d) if n ¬◊X then k ¬X. 'n' picks any world; in a) and b) 'k' asserts a new world; in c) and d) 'k' refers to a known world | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.3) |
| 13141 | Negation: if σ ¬¬X then σ X [Fitting/Mendelsohn] |
| Full Idea: General tableau rule for negation: if σ ¬¬X then σ X | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.2) |
| 13138 | Disj: a) if σ ¬(X∨Y) then σ ¬X and σ ¬Y b) if σ X∨Y then σ X or σ Y [Fitting/Mendelsohn] |
| Full Idea: General tableau rules for disjunctions: a) if σ ¬(X ∨ Y) then σ ¬X and σ ¬Y b) if σ X ∨ Y then σ X or σ Y | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.2) |
| 13142 | Existential: a) if σ ◊X then σ.n X b) if σ ¬□X then σ.n ¬X [n is new] [Fitting/Mendelsohn] |
| Full Idea: General tableau rules for existential modality: a) if σ ◊ X then σ.n X b) if σ ¬□ X then σ.n ¬X , where n introduces some new world (rather than referring to a world that can be seen). | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.2) | |
| A reaction: Note that the existential rule of ◊, usually read as 'possibly', asserts something about a new as yet unseen world, whereas □ only refers to worlds which can already be seen, |
| 13144 | T reflexive: a) if σ □X then σ X b) if σ ¬◊X then σ ¬X [Fitting/Mendelsohn] |
| Full Idea: System T reflexive rules (also for B, S4, S5): a) if σ □X then σ X b) if σ ¬◊X then σ ¬X | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.3) |
| 13145 | D serial: a) if σ □X then σ ◊X b) if σ ¬◊X then σ ¬□X [Fitting/Mendelsohn] |
| Full Idea: System D serial rules (also for T, B, S4, S5): a) if σ □X then σ ◊X b) if σ ¬◊X then σ ¬□X | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.3) |
| 13146 | B symmetric: a) if σ.n □X then σ X b) if σ.n ¬◊X then σ ¬X [n occurs] [Fitting/Mendelsohn] |
| Full Idea: System B symmetric rules (also for S5): a) if σ.n □X then σ X b) if σ.n ¬◊X then σ ¬X [where n is a world which already occurs] | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.3) |
| 13147 | 4 transitive: a) if σ □X then σ.n □X b) if σ ¬◊X then σ.n ¬◊X [n occurs] [Fitting/Mendelsohn] |
| Full Idea: System 4 transitive rules (also for K4, S4, S5): a) if σ □X then σ.n □X b) if σ ¬◊X then σ.n ¬◊X [where n is a world which already occurs] | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.3) |
| 13148 | 4r rev-trans: a) if σ.n □X then σ □X b) if σ.n ¬◊X then σ ¬◊X [n occurs] [Fitting/Mendelsohn] |
| Full Idea: System 4r reversed-transitive rules (also for S5): a) if σ.n □X then σ □X b) if σ.n ¬◊X then σ ¬◊X [where n is a world which already occurs] | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.3) |
| 9740 | If a proposition is possibly true in a world, it is true in some world accessible from that world [Fitting/Mendelsohn] |
| Full Idea: If a proposition is possibly true in a world, then it is also true in some world which is accessible from that world. That is: Γ ||- ◊X ↔ for some Δ ∈ G, ΓRΔ then Δ ||- X. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.6) |
| 9739 | If a proposition is necessarily true in a world, it is true in all worlds accessible from that world [Fitting/Mendelsohn] |
| Full Idea: If a proposition is necessarily true in a world, then it is also true in all worlds which are accessible from that world. That is: Γ ||- □X ↔ for every Δ ∈ G, if ΓRΔ then Δ ||- X. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.6) |
| 13137 | Conj: a) if σ X∧Y then σ X and σ Y b) if σ ¬(X∧Y) then σ ¬X or σ ¬Y [Fitting/Mendelsohn] |
| Full Idea: General tableau rules for conjunctions: a) if σ X ∧ Y then σ X and σ Y b) if σ ¬(X ∧ Y) then σ ¬X or σ ¬Y | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.2) |
| 13140 | Bicon: a)if σ(X↔Y) then σ(X→Y) and σ(Y→X) b) [not biconditional, one or other fails] [Fitting/Mendelsohn] |
| Full Idea: General tableau rules for biconditionals: a) if σ (X ↔ Y) then σ (X → Y) and σ (Y → X) b) if σ ¬(X ↔ Y) then σ ¬(X → Y) or σ ¬(Y → X) | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.2) |
| 13139 | Implic: a) if σ ¬(X→Y) then σ X and σ ¬Y b) if σ X→Y then σ ¬X or σ Y [Fitting/Mendelsohn] |
| Full Idea: General tableau rules for implications: a) if σ ¬(X → Y) then σ X and σ ¬Y b) if σ X → Y then σ ¬X or σ Y | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.2) |
| 13143 | Universal: a) if σ ¬◊X then σ.m ¬X b) if σ □X then σ.m X [m exists] [Fitting/Mendelsohn] |
| Full Idea: General tableau rules for universal modality: a) if σ ¬◊ X then σ.m ¬X b) if σ □ X then σ.m X , where m refers to a world that can be seen (rather than introducing a new world). | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.2) | |
| A reaction: Note that the universal rule of □, usually read as 'necessary', only refers to worlds which can already be seen, whereas possibility (◊) asserts some thing about a new as yet unseen world. |
| 9742 | The system K has no accessibility conditions [Fitting/Mendelsohn] |
| Full Idea: The system K has no frame conditions imposed on its accessibility relation. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.8) | |
| A reaction: The system is named K in honour of Saul Kripke. |
| 13114 | □P → P is not valid in D (Deontic Logic), since an obligatory action may be not performed [Fitting/Mendelsohn] |
| Full Idea: System D is usually thought of as Deontic Logic, concerning obligations and permissions. □P → P is not valid in D, since just because an action is obligatory, it does not follow that it is performed. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.12.2 Ex) |
| 9743 | The system D has the 'serial' conditon imposed on its accessibility relation [Fitting/Mendelsohn] |
| Full Idea: The system D has the 'serial' condition imposed on its accessibility relation - that is, every world must have some world which is accessible to it. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.8) |
| 9744 | The system T has the 'reflexive' conditon imposed on its accessibility relation [Fitting/Mendelsohn] |
| Full Idea: The system T has the 'reflexive' condition imposed on its accessibility relation - that is, every world must be accessible to itself. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.8) |
| 9746 | The system K4 has the 'transitive' condition on its accessibility relation [Fitting/Mendelsohn] |
| Full Idea: The system K4 has the 'transitive' condition imposed on its accessibility relation - that is, if a relation holds between worlds 1 and 2 and worlds 2 and 3, it must hold between worlds 1 and 3. The relation carries over. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.8) |
| 9745 | The system B has the 'reflexive' and 'symmetric' conditions on its accessibility relation [Fitting/Mendelsohn] |
| Full Idea: The system B has the 'reflexive' and 'symmetric' conditions imposed on its accessibility relation - that is, every world must be accessible to itself, and any relation between worlds must be mutual. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.8) |
| 9747 | The system S4 has the 'reflexive' and 'transitive' conditions on its accessibility relation [Fitting/Mendelsohn] |
| Full Idea: The system S4 has the 'reflexive' and 'transitive' conditions imposed on its accessibility relation - that is, every world is accessible to itself, and accessibility carries over a series of worlds. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.8) |
| 9748 | System S5 has the 'reflexive', 'symmetric' and 'transitive' conditions on its accessibility relation [Fitting/Mendelsohn] |
| Full Idea: The system S5 has the 'reflexive', 'symmetric' and 'transitive' conditions imposed on its accessibility relation - that is, every world is self-accessible, and accessibility is mutual, and it carries over a series of worlds. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.8) | |
| A reaction: S5 has total accessibility, and hence is the most powerful system (though it might be too powerful). |
| 9404 | Modality affects content, because P→◊P is valid, but ◊P→P isn't [Fitting/Mendelsohn] |
| Full Idea: P→◊P is usually considered to be valid, but its converse, ◊P→P is not, so (by Frege's own criterion) P and possibly-P differ in conceptual content, and there is no reason why logic should not be widened to accommodate this. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.2) | |
| A reaction: Frege had denied that modality affected the content of a proposition (1879:p.4). The observation here is the foundation for the need for a modal logic. |
| 13112 | In epistemic logic knowers are logically omniscient, so they know that they know [Fitting/Mendelsohn] |
| Full Idea: In epistemic logic the knower is treated as logically omniscient. This is puzzling because one then cannot know something and yet fail to know that one knows it (the Principle of Positive Introspection). | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.11) | |
| A reaction: This is nowadays known as the K-K Problem - to know, must you know that you know. Broadly, we find that externalists say you don't need to know that you know (so animals know things), but internalists say you do need to know that you know. |
| 13111 | Read epistemic box as 'a knows/believes P' and diamond as 'for all a knows/believes, P' [Fitting/Mendelsohn] |
| Full Idea: In epistemic logic we read Υ as 'KaP: a knows that P', and ◊ as 'PaP: it is possible, for all a knows, that P' (a is an individual). For belief we read them as 'BaP: a believes that P' and 'CaP: compatible with everything a believes that P'. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.11) | |
| A reaction: [scripted capitals and subscripts are involved] Hintikka 1962 is the source of this. Fitting and Mendelsohn prefer □ to read 'a is entitled to know P', rather than 'a knows that P'. |
| 13113 | F: will sometime, P: was sometime, G: will always, H: was always [Fitting/Mendelsohn] |
| Full Idea: We introduce four future and past tense operators: FP: it will sometime be the case that P. PP: it was sometime the case that P. GP: it will always be the case that P. HP: it has always been the case that P. (P itself is untensed). | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 1.10) | |
| A reaction: Temporal logic begins with A.N. Prior, and starts with □ as 'always', and ◊ as 'sometimes', but then adds these past and future divisions. Two different logics emerge, taking □ and ◊ as either past or as future. |
| 13728 | The Barcan says nothing comes into existence; the Converse says nothing ceases; the pair imply stability [Fitting/Mendelsohn] |
| Full Idea: The Converse Barcan says nothing passes out of existence in alternative situations. The Barcan says that nothing comes into existence. The two together say the same things exist no matter what the situation. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 4.9) | |
| A reaction: I take the big problem to be that these reflect what it is you want to say, and that does not keep stable across a conversation, so ordinary rational discussion sometimes asserts these formulas, and 30 seconds later denies them. |
| 13729 | The Barcan corresponds to anti-monotonicity, and the Converse to monotonicity [Fitting/Mendelsohn] |
| Full Idea: The Barcan formula corresponds to anti-monotonicity, and the Converse Barcan formula corresponds to monotonicity. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 6.3) |
| 9725 | 'Predicate abstraction' abstracts predicates from formulae, giving scope for constants and functions [Fitting/Mendelsohn] |
| Full Idea: 'Predicate abstraction' is a key idea. It is a syntactic mechanism for abstracting a predicate from a formula, providing a scoping mechanism for constants and function symbols similar to that provided for variables by quantifiers. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], Pref) |
| 13007 | Archimedes defined a straight line as the shortest distance between two points [Archimedes, by Leibniz] |
| Full Idea: Archimedes gave a sort of definition of 'straight line' when he said it is the shortest line between two points. | |
| From: report of Archimedes (fragments/reports [c.240 BCE]) by Gottfried Leibniz - New Essays on Human Understanding 4.13 | |
| A reaction: Commentators observe that this reduces the purity of the original Euclidean axioms, because it involves distance and measurement, which are absent from the purest geometry. |
| 21342 | A relation is internal if two things possessing the relation could not fail to be related [Moore,GE, by Heil] |
| Full Idea: Moore characterises internal relations modally, as those essential to their relata. If a and b are related R-wise, and R is an internal relation, a and b could not fail to be so related; otherwise R is external. | |
| From: report of G.E. Moore (External and Internal Relations [1919]) by John Heil - Relations 'Internal' | |
| A reaction: I don't think of Moore as an essentialist, but this fits the essentialist picture nicely, and is probably best paraphrased in terms of powers. Integers are the standard example of internal relations. |
| 13730 | The Indiscernibility of Identicals has been a big problem for modal logic [Fitting/Mendelsohn] |
| Full Idea: Equality has caused much grief for modal logic. Many of the problems, which have struck at the heart of the coherence of modal logic, stem from the apparent violations of the Indiscernibility of Identicals. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 7.1) | |
| A reaction: Thus when I say 'I might have been three inches taller', presumably I am referring to someone who is 'identical' to me, but who lacks one of my properties. A simple solution is to say that the person is 'essentially' identical. |
| 13725 | □ must be sensitive as to whether it picks out an object by essential or by contingent properties [Fitting/Mendelsohn] |
| Full Idea: If □ is to be sensitive to the quality of the truth of a proposition in its scope, then it must be sensitive as to whether an object is picked out by an essential property or by a contingent one. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 4.3) | |
| A reaction: This incredibly simple idea strikes me as being powerful and important. ...However, creating illustrative examples leaves me in a state of confusion. You try it. They cite '9' and 'number of planets'. But is it just nominal essence? '9' must be 9. |
| 13731 | Objects retain their possible properties across worlds, so a bundle theory of them seems best [Fitting/Mendelsohn] |
| Full Idea: The property of 'possibly being a Republican' is as much a property of Bill Clinton as is 'being a democrat'. So we don't peel off his properties from world to world. Hence the bundle theory fits our treatment of objects better than bare particulars. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 7.3) | |
| A reaction: This bundle theory is better described in recent parlance as the 'modal profile'. I am reluctant to talk of a modal truth about something as one of its 'properties'. An objects, then, is a bundle of truths? |
| 13726 | Counterpart relations are neither symmetric nor transitive, so there is no logic of equality for them [Fitting/Mendelsohn] |
| Full Idea: The main technical problem with counterpart theory is that the being-a-counterpart relation is, in general, neither symmetric nor transitive, so no natural logic of equality is forthcoming. | |
| From: M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 4.5) | |
| A reaction: That is, nothing is equal to a counterpart, either directly or indirectly. |
| 6672 | Moore's Paradox: you can't assert 'I believe that p but p is false', but can assert 'You believe p but p is false' [Moore,GE, by Lowe] |
| Full Idea: Moore's Paradox says it makes no sense to assert 'I believe that p, but p is false', even though it makes perfectly good sense to assert 'I used to believe p, but p is false' or 'You believe p, but p is false'. | |
| From: report of G.E. Moore (works [1905]) by E.J. Lowe - Introduction to the Philosophy of Mind Ch.10 | |
| A reaction: I'm not sure if this really deserves the label of 'paradox'. I take it as drawing attention to the obvious fact that belief is commitment to truth. I think my assessment that p is true is correct, but your assessment is wrong. ('True' is not redundant!) |
| 20147 | Arguments that my finger does not exist are less certain than your seeing my finger [Moore,GE] |
| Full Idea: This really is a finger ...and you all know it. ...I can safely challenge anyone to give an argument that it is not true, which does not rest upon some premise which is less certain than is the proposition which it is designed to attack. | |
| From: G.E. Moore (Some Judgements of Perception [1922], p.228), quoted by John Kekes - The Human Condition 01.3 | |
| A reaction: [In Moore's 'Philosophical Studies'] This is a particularly clear statement from Moore of his famous claim. I'm not sure what to make of an attempt to compare a sceptical argument (dreams, demons) with the sight of a finger. |
| 6349 | I can prove a hand exists, by holding one up, pointing to it, and saying 'here is one hand' [Moore,GE] |
| Full Idea: I can prove now that two human hands exist. How? By holding up my two hands, and saying, as I make a certain gesture with the right hand, 'Here is one hand', and adding, as I gesture with the left, 'and here is another'. | |
| From: G.E. Moore (Proof of an External World [1939], p.1) | |
| A reaction: The words need to be spoken, presumably, so that what he is doing fits into the linguistic conventions of what will normally be accepted as a proof. In fact, just holding the hand up seems enough. The proof begs the question of virtual reality. |
| 22302 | Moor bypassed problems of correspondence by saying true propositions ARE facts [Moore,GE, by Potter] |
| Full Idea: Moore avoided the problematic correspondence between propositions and reality by identifying the former with the latter; the world consists of true propositions, and there is no difference between a true proposition and the fact that makes it true. | |
| From: report of G.E. Moore (The Nature of Judgement [1899]) by Michael Potter - The Rise of Analytic Philosophy 1879-1930 28 'Refut' | |
| A reaction: This is "the most platonic system of modern times", he wrote (letter 14.8.1898). He then added platonist ethics. This is a pernicious and absurd doctrine. The obvious problem is that false propositions can be indistinguishable, but differ in ontology. |
| 7526 | Hegelians say propositions defy analysis, but Moore says they can be broken down [Moore,GE, by Monk] |
| Full Idea: Moore rejected the Hegelian view, that a proposition is a unity that defies analysis; instead, it is a complex that positively cries out to be broken up into its constituent parts, which parts Moore called 'concepts'. | |
| From: report of G.E. Moore (The Nature of Judgement [1899]) by Ray Monk - Bertrand Russell: Spirit of Solitude Ch.4 | |
| A reaction: Russell was much influenced by this idea, though it may be found in Frege. Anglophone philosophers tend to side instantly with Moore, but the Hegel view must be pondered. An idea comes to us in a unified flash, before it is articulated. |
| 21233 | The beautiful is whatever it is intrinsically good to admire [Moore,GE] |
| Full Idea: The beautiful should be defined as that of which the admiring contemplation is good in itself. | |
| From: G.E. Moore (Principia Ethica [1903], p.210), quoted by Graham Farmelo - The Strangest Man | |
| A reaction: To work, this definition must exclude anything else which it is intrinsically good to admire. Good deeds obviously qualify for that, so good deeds must be intrinsically beautiful (which would be agreed by ancient Greeks). We can't ask WHY it is good! |
| 8039 | Moore tries to show that 'good' is indefinable, but doesn't understand what a definition is [MacIntyre on Moore,GE] |
| Full Idea: Moore tries to show that 'good' is indefinable by relying on a bad dictionary definition of 'definition'. | |
| From: comment on G.E. Moore (Principia Ethica [1903]) by Alasdair MacIntyre - After Virtue: a Study in Moral Theory Ch.2 | |
| A reaction: An interesting remark, with no further explanation offered. If Moore has this problem, then Plato had it too (see Idea 3032). I would have thought that any definition MacIntyre could offer would either be naturalistic, or tautological. |
| 22151 | The Open Question argument leads to anti-realism and the fact-value distinction [Boulter on Moore,GE] |
| Full Idea: Moore's Open Question argument led, however unintentionally, to the rise of anti-realism in meta-ethics (which leads to distinguishing values from facts). | |
| From: comment on G.E. Moore (Principia Ethica [1903]) by Stephen Boulter - Why Medieval Philosophy Matters 4 | |
| A reaction: I presume that Moore proves that the Good is not natural, and after that no one knows what it is, so it seems to be arbitrary or non-existent (rather than the platonic fact that Moore had hoped for). I vote for naturalistic ethics. |
| 11056 | The naturalistic fallacy claims that natural qualties can define 'good' [Moore,GE] |
| Full Idea: The naturalistic fallacy ..consists in the contention that good means nothing but some simple or complex notion, that can be defined in terms of natural qualities. | |
| From: G.E. Moore (Principia Ethica [1903], §044) | |
| A reaction: Presumably aimed at those who think morality is pleasure and pain. We could hardly attribute morality to non-human qualities. I connect morality to human deliberative functions. |
| 8033 | Moore cannot show why something being good gives us a reason for action [MacIntyre on Moore,GE] |
| Full Idea: Moore's account leaves it entirely unexplained and inexplicable why something's being good should ever furnish us with a reason for action. | |
| From: comment on G.E. Moore (Principia Ethica [1903]) by Alasdair MacIntyre - A Short History of Ethics Ch.18 | |
| A reaction: The same objection can be raised to Plato's Form of the Good, but Plato's answer seems to be that the Good is partly a rational entity, and partly that the Good just has a natural magnetism that makes it quasi-religious. |
| 8032 | Can learning to recognise a good friend help us to recognise a good watch? [MacIntyre on Moore,GE] |
| Full Idea: How could having learned to recognize a good friend help us to recognize a good watch? Yet is Moore is right, the same simple property is present in both cases? | |
| From: comment on G.E. Moore (Principia Ethica [1903]) by Alasdair MacIntyre - A Short History of Ethics Ch.18 | |
| A reaction: It begins to look as if what they have in common is just that they both make you feel good. However, I like the Aristotelian idea that they both function succesfully, one as a timekeeper, the other as a citizen or companion. |
| 11050 | Moore's combination of antinaturalism with strong supervenience on the natural is incoherent [Hanna on Moore,GE] |
| Full Idea: Moore incoherently combines his antinaturalism with the thesis that intrinsic-value properties are logically strongly supervenient on (or explanatorily reducible to) natural facts. | |
| From: comment on G.E. Moore (Principia Ethica [1903]) by Robert Hanna - Rationality and Logic Ch.1 | |
| A reaction: I take this to be Moore fighting shy of the strongly Platonist view of values which his arguments all seemed to imply. |
| 23726 | Despite Moore's caution, non-naturalists incline towards intuitionism [Moore,GE, by Smith,M] |
| Full Idea: Although Moore was reluctant to adopt it, the epistemology the non-naturalists tended to favour was intuitionism. | |
| From: report of G.E. Moore (Principia Ethica [1903]) by Michael Smith - The Moral Problem 2.2 | |
| A reaction: Moore was presumably reluctant because intuitionism had been heavily criticised in the past for its inability to settle moral disputes. But if you insist that goodness is outside nature, what other means of knowing it is available? Reason? |
| 18676 | We should ask what we would judge to be good if it existed in absolute isolation [Moore,GE] |
| Full Idea: It is necessary to consider what things are such that, if they existed by themselves, in absolute isolation, we should yet judge their existence to be good. | |
| From: G.E. Moore (Principia Ethica [1903], §112) | |
| A reaction: This is known as the 'isolation test'. The test has an instant appeal, but looks a bit odd after a little thought. The value of most things drains out of them if they are totally isolated. The MS of the Goldberg Variations floating in outer space? |
| 11057 | It is always an open question whether anything that is natural is good [Moore,GE] |
| Full Idea: Good does not, by definition, mean anything that is natural; and it is therefore always an open question whether anything that is natural is good. | |
| From: G.E. Moore (Principia Ethica [1903], §027) | |
| A reaction: This is the best known modern argument for Platonist idealised ethics. But maybe there is no end to questioning anywhere, so each theory invites a further question, and nothing is ever fully explained? Next stop - pragmatism. |
| 5925 | The three main values are good, right and beauty [Moore,GE, by Ross] |
| Full Idea: Moore describes rightness and beauty as the two main value-attributes, apart from goodness. | |
| From: report of G.E. Moore (Principia Ethica [1903]) by W. David Ross - The Right and the Good §IV | |
| A reaction: This was a last-throw of the Platonic ideal, before we plunged into the value-free world of Darwin and the physicists. It is hard to agree with Moore, but also hard to disagree. Why do many people despise or ignore these values? |
| 5902 | For Moore, 'right' is what produces good [Moore,GE, by Ross] |
| Full Idea: Moore claims that 'right' means 'productive of the greatest possible good'. | |
| From: report of G.E. Moore (Principia Ethica [1903]) by W. David Ross - The Right and the Good §I | |
| A reaction: Ross is at pains to keep 'right' and 'good' as quite distinct notions. Some actions are right but very unpleasant, and seem to produce no real good at all. |
| 5903 | 'Right' means 'cause of good result' (hence 'useful'), so the end does justify the means [Moore,GE] |
| Full Idea: 'Right' does and can mean nothing but 'cause of a good result', and is thus identical with 'useful', whence it follows that the end always will justify the means. | |
| From: G.E. Moore (Principia Ethica [1903], §089) | |
| A reaction: Of course, Moore does not identify utility with pleasure, as his notion of what is good concerns fairly Platonic ideals. Would Stalin's murders have been right if Russia were now the happiest nation on Earth? |
| 5907 | Relationships imply duties to people, not merely the obligation to benefit them [Ross on Moore,GE] |
| Full Idea: Moore's 'Ideal Utilitarianism' seems to unduly simplify our relations to our fellows. My neighbours are merely possible beneficiaries by my action. But they also stand to me as promiser, creditor, husband, friend, which entails prima facie duties. | |
| From: comment on G.E. Moore (Principia Ethica [1903]) by W. David Ross - The Right and the Good §II | |
| A reaction: Perhaps it is better to say that we have obligations to benefit particular people, because of our obligations, and that we are confined to particular benefits which meet those obligations - not just any old benefit to any old person. |