111 ideas
| 14001 | People who use science to make philosophical points don't realise how philosophical science is [Markosian] |
| Full Idea: When people give arguments from scientific theories to philosophical conclusions, there is usually a good deal of philosophy built into the relevant scientific theories. | |
| From: Ned Markosian (A Defense of Presentism [2004], 3.9) | |
| A reaction: I love this remark, being thoroughly fed up with knowledgeable scientists who are naïve about philosophy, and think their current theory demolishes long-lasting aporiai. They are up to their necks in philosophy. |
| 20910 | Everything happens necessarily, and for a reason [Democritus] |
| Full Idea: Nothing happens at random, but everything for a reason and as the effect of necessity. | |
| From: Democritus (fragments/reports [c.431 BCE], B002), quoted by Pseudo-Plutarch - On the Doctrine of the Philosophers 1.25.4 | |
| A reaction: [In Aetius 'Stob'] This remark reminds us of the link between necessity and sufficient reason. Do all reasons arise for a reason? |
| 13991 | Presentism has the problem that if Socrates ceases to exist, so do propositions about him [Markosian] |
| Full Idea: Presentism has a problem with singular propositions about non-present objects. ...When Socrates popped out of existence, according to Presentism, all those singular propositions about him also popped out of existence. | |
| From: Ned Markosian (A Defense of Presentism [2004], 2.1) | |
| A reaction: He seems to treat propositions in a Russellian way, as things which exist independently of thinkers, which I struggle to grasp. Markosian offers various strategies for this [§3.5]. |
| 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) |
| 16146 | Two can't be a self-contained unit, because it would need to be one to do that [Democritus, by Aristotle] |
| Full Idea: Democritus claimed that one substance could not be composed from two nor two from one. …The same will clearly go for number, on the popular assumption that number is a combination of units. Unless two is one, it cannot contain a unit in actuality. | |
| From: report of Democritus (fragments/reports [c.431 BCE]) by Aristotle - Metaphysics 1039a15 | |
| A reaction: Chrysippus followed this up the first part with the memorable example of Dion and Theon. The problem with the second part is that 2, 3 and 4 are three numbers, so they can count as meta-units. |
| 20901 | True Being only occurs when it is completely full, with atoms and no void [Democritus, by Aristotle] |
| Full Idea: In response to defenders of the One, Democritus says that what is, in the proper sense, is being that is completely full, but that such a being is not one, but that they are unlimited in number and invisible because of the smallness of their masses. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A007) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 325a28 | |
| A reaction: Democritus is in a tangle here. He says proper being has no void, having apparently conceded that motion needs void (which he admits is non-existent). So true being only occurs when everything grinds to a halt, which is not now. But Idea 20902. |
| 20902 | Being does not exist more than non-being [Democritus, by Aristotle] |
| Full Idea: They say that being does not exist more than non-being, because neither does the void exist more than the body. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A006) by Aristotle - Metaphysics 0985b09 | |
| A reaction: The claim that Being and Non-Being are the same thing is pretty startling. It seems to be an expedient to get Void into the picture, even though it is taken to be wholly devoid of qualities. |
| 20904 | The non-existent exists as much as the existent, because it has causal powers [Democritus] |
| Full Idea: What exists does not exist at all more than what does not exist, and both are causes in a similar way for the things that come about. | |
| From: Democritus (fragments/reports [c.431 BCE], A008), quoted by Simplicius - On Aristotle's 'Physics' p.28.4-27 | |
| A reaction: [Simplicius actually attributes this to the shadowy Leucippus] You can see the point. If you drive into a pothole, that has considerable causal powers. |
| 20903 | The only distinctions are Configuration (shape), Disposition (order) and Turning (position) [Democritus, by Aristotle] |
| Full Idea: They say that what is differs only by Configuration ([rhusmos], which is the shape), by Disposition ([diathege], which is the order), and by Turning ([tropê], which is the position. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A006) by Aristotle - Metaphysics 0985b16 | |
| A reaction: If you give the shape, structure and position of an object, there is no much more to say. Perhaps mention time. |
| 20893 | Nothing comes from non-existence, or passes into it [Democritus, by Diog. Laertius] |
| Full Idea: Nothing comes into being from what does not exist, nor is it destroyed into what does not exist. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A001) by Diogenes Laertius - Lives of Eminent Philosophers 09.44 | |
| A reaction: [part of a concise summary of Democritus by DL] Probably an intuition about conservation laws, rather than a speculation about the Big Bang. |
| 20896 | It is not possible to know what sort each thing is [Democritus] |
| Full Idea: In reality [eteé] to recognise what sort each thing is, belongs to what is impracticable [aporos]. | |
| From: Democritus (fragments/reports [c.431 BCE], B008), quoted by Sextus Empiricus - Against the Logicians (two books) 7.137 | |
| A reaction: On the whole modern scientists (and the rest of us) shoehorn virtually everything into a specific category. It strikes me as wildly bad metaphysics to say that everything necessarily has its category. |
| 3357 | Democritus denies reality to large objects, because atomic entities can't combine to produce new ones [Benardete,JA on Democritus] |
| Full Idea: Democritus appears to rule out from his austere ontology all so-called emergent entities - even mountains and rivers - on the ground that two or more entities can never combine to produce a new one. | |
| From: comment on Democritus (fragments/reports [c.431 BCE]) by José A. Benardete - Metaphysics: the logical approach Ch.24 |
| 598 | Democritus said that substances could never be mixed, so atoms are the substances [Democritus, by Aristotle] |
| Full Idea: Democritus claimed that one substance could not be composed from two nor two from one; for him it is the atoms that are the substances. | |
| From: report of Democritus (fragments/reports [c.431 BCE]) by Aristotle - Metaphysics 1039a10 |
| 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. |
| 14002 | Possible worlds must be abstract, because two qualitatively identical worlds are just one world [Markosian] |
| Full Idea: Possible worlds are just abstract objects that play a certain role in philosophers' talk about modality. They are ways things could be. That's why there are no two abstract possible worlds which are qualitatively identical. They count as one world. | |
| From: Ned Markosian (A Defense of Presentism [2004], 3.10) | |
| A reaction: Brilliant! This looks like the best distinction between concrete and abstract. If two concreta are identical they remain two; if two abstracta are identical they are one (like numbers, or logical connectives with the same truth table). |
| 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. |
| 1532 | Sensible qualities can't be real if they appear different to different creatures [Democritus, by Theophrastus] |
| Full Idea: As proof of the fact that sensible qualities have no real existence he points to the fact that they do not appear the same to all creatures. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A135) by Theophrastus - On the Senses 63 |
| 20894 | Man is separated from reality [Democritus] |
| Full Idea: It is necessary to recognise that man by virtue of this criterion is separated from reality. | |
| From: Democritus (fragments/reports [c.431 BCE], B006), quoted by Sextus Empiricus - Against the Logicians (two books) 7.137 | |
| A reaction: I don't know what 'this criterion' is, but it strikes me as quite a good slogan for fans (like myself) of the representative theory of perception. Critics say it is the big objection to the representative theory, but I say 'get over it'. |
| 517 | All evidence comes from senses, so they are indispensable to the mind [Democritus] |
| Full Idea: Mind must never reject the senses, because that is where it gets its evidence, and it would be the mind's downfall. | |
| From: Democritus (fragments/reports [c.431 BCE], B125), quoted by Galen - On Medical Experience 15.8 |
| 20897 | Obscure knowledge belongs to the five senses, and genuine knowledge is the other type [Democritus] |
| Full Idea: There are two forms of knowledge [gnomé], the one genuine, the other obscure. And to the obscure one belongs all of these: sight, hearing, smell, taste, touch. The other is genuine, and is separated from this one. | |
| From: Democritus (fragments/reports [c.431 BCE], B011), quoted by Sextus Empiricus - Against the Logicians (two books) 7.139 | |
| A reaction: [Sextus goes on to make it clear that the 'genuine' one is knowledge acquired by thought]. I take Parmenides to be the first rationalist. It is interesting that Democritus, who devoted his life to finding causal explanations, seems to be a rationalist. |
| 577 | Democritus says there is either no truth, or it is concealed from us [Democritus, by Aristotle] |
| Full Idea: Democritus concludes that either there is no truth or it is concealed from us. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A112) by Aristotle - Metaphysics 1009b12 |
| 20895 | We actually know nothing, and opinions are mere flux [Democritus] |
| Full Idea: Certainly this argument too makes it clear that in reality [eteé] we know nothing about anything, but for each person opinion is a rhythmic afflux [epirhusmié]. | |
| From: Democritus (fragments/reports [c.431 BCE], B007), quoted by Sextus Empiricus - Against the Logicians (two books) 7.137 | |
| A reaction: This seems to pick 'all is flux' up from Heraclitus, and make Democritus (along with aspects of Socrates) the true source of ancient scepticism. |
| 1528 | We in fact know nothing, but we each restructure our reality with beliefs [Democritus] |
| Full Idea: In reality we know nothing about anything, but belief restructures things for each of us. | |
| From: Democritus (fragments/reports [c.431 BCE], B007), quoted by Sextus Empiricus - Against the Professors (six books) 7.136 |
| 492 | It is obviously impossible to understand the reality of each thing [Democritus] |
| Full Idea: It will be obvious that it is impossible to understand how in reality each thing is. | |
| From: Democritus (fragments/reports [c.431 BCE], B008), quoted by Sextus Empiricus - Against the Professors (six books) 7.137 |
| 515 | We know nothing in reality; for truth lies in an abyss [Democritus] |
| Full Idea: We know nothing in reality; for truth lies in an abyss. | |
| From: Democritus (fragments/reports [c.431 BCE], B117), quoted by Diogenes Laertius - Lives of Eminent Philosophers 09.72.10 |
| 20892 | Democritus was devoted to discovering causal explanations [Democritus, by Eusebius] |
| Full Idea: Democritus himself, as they say, stated that he would rather discover a single causal explanation [aitiologia] than become the King of the Persians. | |
| From: report of Democritus (fragments/reports [c.431 BCE], B118) by Eusebius - Preparation for the Gospel 14.27.4 | |
| A reaction: Democritus seems to be clearly the father of the physical sciences, because he focused single-mindedly on physical and causal explanations. David Lewis says all explanations are causal. |
| 5882 | Democritus says soul consists of smooth round bodies brought together in accidental collision [Democritus, by Cicero] |
| Full Idea: Since Democritus makes the soul consist of minute smooth round bodies brought together in some sort of accidental collision, let us pass him over. | |
| From: report of Democritus (fragments/reports [c.431 BCE]) by M. Tullius Cicero - Tusculan Disputations I.xi.23 | |
| A reaction: If we accept that Democritus thought the collision of atoms 'accidental', then it doesn't sound like a very good theory. What would Cicero say if we replaced 'accidental' with 'naturally selected'? |
| 6034 | Atomists say soul has a rational part in the chest, and a diffused non-rational part [Democritus, by Aetius] |
| Full Idea: Democritus and Epicurus say the soul has two parts, one which is rational and is situated in the chest area, and the other which is non-rational and is spread throughout the entire compound of the body. | |
| From: report of Democritus (fragments/reports [c.431 BCE]) by Aetius - fragments/reports 4.4.6 | |
| A reaction: The spread part corresponds to such things as feeling fear in the stomach, or excitement throughout the limbs. I can't think what grounds there would be for choosing the chest as the home of reason. I suppose you can hear reason thumping in there.. |
| 20912 | The soul is the same as the mind [Democritus, by Aristotle] |
| Full Idea: Democritus says the soul is the same thing as the mind. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A101) by Aristotle - De Anima 405a10 | |
| A reaction: This is not in contrast to the Christian concept of the soul, but in contrast to the normal view of psuché, which is more like the life that permeates the whole body. Democritus was more in tune than Aristotle with modern thought on this. |
| 20916 | Animals have a share of reason [Democritus, by Porphyry] |
| Full Idea: Democritus recognised that animals have a share of reason. | |
| From: report of Democritus (fragments/reports [c.431 BCE]) by Porphyry - On Abstinence 3.6.7 | |
| A reaction: Since he considers thinking to be the interaction of atoms in the body, which animals evidently possess, this seems consistent. No one seems to observed animals closely before the 20th century, other than to exploit them. |
| 20914 | The directive centre is located in the whole head [Democritus, by Ps-Plutarch] |
| Full Idea: Democritus says [the directive centre is located] in the whole head. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A105) by Pseudo-Plutarch - On the Doctrine of the Philosophers 4.5.1 | |
| A reaction: The whole head is not quite the brain, but he is getting very warm indeed, and long before anyone else got so close. |
| 6033 | Democritus said everything happens of necessity, by natural motion of atoms [Democritus, by Cicero] |
| Full Idea: Democritus, the founder of atomism, preferred to accept that all things happened by necessity than to tear from the atomic bodies their natural motions. | |
| From: report of Democritus (fragments/reports [c.431 BCE]) by M. Tullius Cicero - On Fate ('De fato') §22 | |
| A reaction: This is in opposition to Epicurus, who said that atoms can have a 'swerve', making free will possible. It is suggested that Epicurus was the first to really grasp the problem of free will. Democritus was just stating the (to him) obvious. |
| 5088 | Some say there is a determinate cause for every apparently spontaneous event [Democritus, by Aristotle] |
| Full Idea: Some people (Democritus?) say there is no such thing as a chance event; they claim that there is always a determinate cause for everything which is said to be a chance or a spontaneous event. | |
| From: report of Democritus (fragments/reports [c.431 BCE]) by Aristotle - Physics 195b37 | |
| A reaction: This is the mutual implication of physicalism and determinism, which strikes me as unavoidable. I say: don't panic about morality because determinism is true. Embrace determinism - it is harmless and true. Its opposite is a nonsense. |
| 21670 | Democritus said atoms only move by their natural motions, which are therefore necessary [Democritus, by Cicero] |
| Full Idea: The author of the atomic theory, Democritus, preferred to accept the view that all events are caused by necessity, rather than to deprive the atoms of their natural motions. | |
| From: report of Democritus (fragments/reports [c.431 BCE]) by M. Tullius Cicero - On Fate ('De fato') 10.23 | |
| A reaction: The 'deprivation' would have to be caused by mind, or by the later 'swerve' of Epicurus. |
| 24041 | Democritus says spherical atoms are fire, and constitute the soul [psuche] [Democritus, by Aristotle] |
| Full Idea: Democritus says the soul is a sort of fire. For the shapes and atoms are unlimitied and those that are spherical he says are fire and soul - which are like the motes in the air when sunbeams come through the window. | |
| From: report of Democritus (fragments/reports [c.431 BCE], DK 67-68) by Aristotle - De Anima 403b31 | |
| A reaction: It's hard to see why the spherical atoms should be fire. Maybe because they move together quickly and easily. …At 404a5 Aristotle agrees with me! |
| 20913 | Democritus says the soul is the body, and thinking is thus the mixture of the body [Democritus, by Theophrastus] |
| Full Idea: Democritus explains thinking by the mixture of the body, which is surely in accordance with his reasoning, since he makes the soul the body. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A135) by Theophrastus - On the Senses 58 | |
| A reaction: I agree with Democritus. |
| 14000 | 'Grabby' truth conditions first select their object, unlike 'searchy' truth conditions [Markosian] |
| Full Idea: We can talk of 'grabby' truth conditions (where an object is grabbed before predication) and 'searchy' truth conditions (where the object is included in what is being asserted). | |
| From: Ned Markosian (A Defense of Presentism [2004], 3.8) | |
| A reaction: [He credits Tom Ryckman with the terminology] I am inclined to think that the whole of language is 'searchy', even when it appears to be blatantly 'grabby'. Even ostensive reference is an act of hope rather than certainty. |
| 1540 | Pleasure and pain guide our choices of good and bad [Democritus] |
| Full Idea: The guides to what is good and bad for people are pleasure and pain. | |
| From: Democritus (fragments/reports [c.431 BCE], B188), quoted by John Stobaeus - Anthology 3.01.46 |
| 495 | Wisdom creates a healthy passion-free soul [Democritus] |
| Full Idea: Medicine heals diseases of the body, wisdom frees the soul from passions. | |
| From: Democritus (fragments/reports [c.431 BCE], B031), quoted by Clement - Pedagogue 1.6.2.1 | |
| A reaction: The interesting concept of a healthy mind seems to have got lost in modern moral philosophy. |
| 1537 | Happiness is identifying and separating the pleasures [Democritus, by Stobaeus] |
| Full Idea: Democritus thinks that happiness consists in the determination and separation of pleasures, and that this is what is both finest and most beneficial for people. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A167) by John Stobaeus - Anthology 2.07.3 | |
| A reaction: A great deal of the strategy and ethics of living consists (if you are lucky) of discriminating among possible pleasures. Philosophers should produce criteria. |
| 20917 | Contentment comes from moderation and proportion in life [Democritus, by Stobaeus] |
| Full Idea: Contentment [euthumia] comes about for human beings from the moderation of enjoyment and proportion [summetria] in life. | |
| From: report of Democritus (fragments/reports [c.431 BCE], B191) by John Stobaeus - Anthology 3.1.210 | |
| A reaction: This is close to Aristotle's doctrine of the Mean. The majority of ethical ideas attributed to Democritus (presumably by the Epicureans) are thought to be spurious. This idea actually sounds rather stoic. |
| 13551 | Democritus says wealth is a burden to the virtuous mind [Democritus, by Seneca] |
| Full Idea: Democritus rejected wealth, regarding it as a burden to the virtuous mind. | |
| From: report of Democritus (fragments/reports [c.431 BCE]) by Seneca the Younger - On Providence §6 | |
| A reaction: The rival view is that wealth empowers a virtuous person to perform more fine deeds. Democritus seems to have a rather solitary view of virtue. |
| 20899 | Atoms cling together, until a stronger necessity disperses them [Democritus, by Aristotle] |
| Full Idea: Democritus thinks that the substances hold on to one another and remain together for a length of time until some stronger necessity arising from their surroundings shakes and disperses them. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A037) by Aristotle - On Democritus (frag) | |
| A reaction: [quoted in Simplicius, Commentary on Aristotle's On the Heavens] He's not wrong. This seems to provide a mechanism for the Heracltean flux. Ancient critics wanted to know where the 'stronger necessity' came from. |
| 20898 | Atoms are irregular, hooked, concave, convex, and many other shapes [Democritus, by Aristotle] |
| Full Idea: Some substances are irregular, others hook-shaped, other concave, other convex, others provided with innumerable other differences. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A037) by Aristotle - On Democritus (frag) | |
| A reaction: [quoted in Simplicius, Commentary on Aristotle's On the Heavens] 'Substance' here means a fundamental object, which for Democritus is an undividable atom. |
| 20908 | There could be an atom the size of the world [Democritus, by Ps-Plutarch] |
| Full Idea: Democritus say that it is possible that there exists an atom of the size of the world. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A047) by Pseudo-Plutarch - On the Doctrine of the Philosophers 1.12.6 | |
| A reaction: The editor says this may have been a criticism of Democritus - presumably a reductio ad absurdum. But Democritus has no upper limit on the size of an atom. It challenges the imagination to treat such a huge thing as indivisible. |
| 1527 | There must be atoms, to avoid the absurdity of infinite division down to nothing [Democritus, by Aristotle] |
| Full Idea: If everything is infinitely divided, what survives the divisions? Alternatively, division would end at points with no magnitude, in which case bodies are composed of nothing. This is the argument claiming there are atoms of some magnitude. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A048b) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 316a14- |
| 493 | Experiences are merely convention; only atoms and the void are real [Democritus] |
| Full Idea: Sweet exists by convention, bitter by convention, colour by convention; atoms and void alone exist in reality. | |
| From: Democritus (fragments/reports [c.431 BCE], B009), quoted by Sextus Empiricus - Against the Logicians (two books) 7.135 |
| 20909 | The basic atoms are without qualities - which only arise from encounters between atoms [Democritus, by Galen] |
| Full Idea: Democritus and the Epicureans posit that the first element is without quality, possessing by nature neither whiteness, blackness, sweetness or bitterness, warmth or cold. ...It is from the encounter of the atoms that all the sensible qualities come about. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A049) by Galen - On Hippocrates and Plato 1.2 | |
| A reaction: Idea 493 comes in the middle of this summary by Galen. Hence atoms play the role that substrates play in object-based metaphysics. So atoms have the same problem. Is the shape of an atom a quality of an atom. Or are qualities what atoms DO? |
| 1536 | If a cone is horizontally sliced the surfaces can't be equal, so it goes up in steps [Democritus] |
| Full Idea: If a cone is cut parallel to the base are the two new surfaces equal or unequal? If they are unequal, the cone must have gone up in steps. If they are equal then the cone must have been a cylinder, which is absurd. | |
| From: Democritus (fragments/reports [c.431 BCE], B155), quoted by Plutarch - 72: Against Stoics on common Conceptions 1079e1 |
| 17542 | 'Full' and 'Void' secularised Parmenides's Being and Not-being [Democritus, by Heisenberg] |
| Full Idea: In atomism, the antithesis of Being and Not-being of Parmenides is secularised into the antithesis of the 'Full' and the 'Void'. | |
| From: report of Democritus (fragments/reports [c.431 BCE]) by Werner Heisenberg - Physics and Philosophy 04 |
| 1525 | Atomists say there are only three differences - in shape, arrangement and position [Democritus, by Aristotle] |
| Full Idea: Democritus and Leucippus say that there are only three differences - in shape, arrangement and position. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A006) by Aristotle - Metaphysics 0985b15 |
| 5947 | If only atoms are real and the rest is convention, we wouldn't bother to avoid pain [Democritus, by Diogenes of Oen.] |
| Full Idea: Democritus erred when he said that the atoms alone exist in truth among realities, but everything else is convention; for then, far from discovering the truth, we shall not even be able to live, since we shall avoid neither fire nor wounds. | |
| From: report of Democritus (fragments/reports [c.431 BCE]) by Diogenes (Oen) - fragments/reports F2 7 | |
| A reaction: The point is that we have to treat pain as a reality, not just as a convention. I suspect that Diogenes is making the same mistake made by modern attackers of 'eliminativism'. It is all about identity and reduction and levels of reality… |
| 13219 | When atoms touch, why don't they coalesce, like water drops? [Aristotle on Democritus] |
| Full Idea: Why, when they come into contact, do they [atoms] not coalesce into one, as drops of water run together when drop touches drop? | |
| From: comment on Democritus (fragments/reports [c.431 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 326a33 | |
| A reaction: Presumably we must think of atoms as having basic ontological unity, rather than as being little globules of 'stuff'. They are more like monads than they are like mud. |
| 1533 | Because appearance is infinitely varied, atomists assume infinitely many shapes of atom [Democritus, by Aristotle] |
| Full Idea: They thought that truth lay in appearances, which they appreciated are contradictory and infinite, so they made the shapes of atoms infinite. Thus the infinite changes in compounds create the infinitely varies appearances. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A009) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 315b9 |
| 23314 | Greeks explained regularity by intellectual design, not by laws [Democritus, by Frede,M] |
| Full Idea: It is clear that Democritus had no idea of laws of nature …for in Greek thought regularity of behaviour is associated with design by an intellect. | |
| From: report of Democritus (fragments/reports [c.431 BCE]) by Michael Frede - A Free Will Intro | |
| A reaction: Ah. A simple realisation…! Seventeenth century laws of nature offered an explanation of natural order which didn't rely on God. Even though those scientists were all theists. |
| 24059 | Democritus is wrong: in a void we wouldn't see a distant ant in exact detail [Aristotle on Democritus] |
| Full Idea: Democritus did not speak correctly in supposing that if the intermediate space became a void, we would see an ant in exact detail if it were up in the heaven. …If the intermediate space became a void, rather nothing would be seen at all. | |
| From: comment on Democritus (fragments/reports [c.431 BCE]) by Aristotle - De Anima 419a15 | |
| A reaction: Depends what you mean by void, but Aristotle is nearer the truth. Is vision clearer in outer space than in our higher atmosphere? |
| 5101 | Movement is impossible in a void, because nothing can decide the direction of movement [Aristotle on Democritus] |
| Full Idea: Void makes it impossible for anything to move, since in a void there is nowhere for a thing to move to more or less than anywhere else, because the void by definition contains no differentiation. | |
| From: comment on Democritus (fragments/reports [c.431 BCE]) by Aristotle - Physics 214b32 | |
| A reaction: A lovely application of the Principle of Sufficient Reason. However this assumes that the cause of the movement is going to be in the void (telos?), rather than in the body which will move (modern causation?). |
| 20905 | Growth and movement would not exist if there were no void to receive them [Democritus] |
| Full Idea: They say that one argument for void is that otherwise local motion (that is, locomotion and growth) would not exist: for there would not seem to be motion if there were no void, for what is full is incapable of receiving anything. | |
| From: Democritus (fragments/reports [c.431 BCE], A019), quoted by Aristotle - Physics 213b03 | |
| A reaction: The modern concept of a 'field' seems to have removed the possibility of a genuine 'void'. |
| 13990 | Presentism is the view that only present objects exist [Markosian] |
| Full Idea: According to Presentism, if we were to make an accurate list of all the things that exist (within the range of our most unrestricted quantifiers) there would not be a single non-present object on the list. | |
| From: Ned Markosian (A Defense of Presentism [2004], 1) | |
| A reaction: An immediate problem that needs examing is what constitutes an 'object'. It had better not range over time (like an journey). It would be hard to fit a description like 'the oldest man in England'. |
| 13992 | Presentism says if objects don't exist now, we can't have attitudes to them or relations with them [Markosian] |
| Full Idea: If there are no non-present objects (according to Presentism), then no one can now stand in any relation to any non-present object. You cannot now 'admire' Socrates, and no present event has a causal relation to Washington crossing the Delaware. | |
| From: Ned Markosian (A Defense of Presentism [2004], 2.2) | |
| A reaction: You can have an overlapping causal chain that gets you back to Washington, and a causal chain can connect Socrates to our thoughts about him (as in baptismal reference). A simple reply needs an 'overlap' though. |
| 13994 | Presentism seems to entail that we cannot talk about other times [Markosian] |
| Full Idea: It is very natural to talk about times, ...but Presentism seems to entail that we never say anything about any such times. | |
| From: Ned Markosian (A Defense of Presentism [2004], 2.4) | |
| A reaction: I'm beginning to think that Markosian is in the grips of a false notion of proposition, as something that exists independently of thinkers, and is entailed by the facts and objects of reality. This is not what language does. |
| 13995 | Serious Presentism says things must exist to have relations and properties; Unrestricted version denies this [Markosian] |
| Full Idea: Mark Hinchliff distinguishes between 'Serious' Presentism (objects only have relations and properties when they exist) and 'Unrestricted' Presentism (objects can have relations and properties even when they don't exist). | |
| From: Ned Markosian (A Defense of Presentism [2004], 3.1) | |
| A reaction: [Hinchliff 1996:124-6] Markosian votes for the Serious version, as being the only true Presentism. I think he is muddling language and reality, predicates and properties. |
| 13996 | Maybe Presentists can refer to the haecceity of a thing, after the thing itself disappears [Markosian] |
| Full Idea: Some Presentists (such as Adams) believe that a haecceity (a property unique to some entity) continues to exist even after its object ceases to exist. A sentence about Socrates still expresses a proposition, about 'Socraticity'. | |
| From: Ned Markosian (A Defense of Presentism [2004], 3.4) | |
| A reaction: [Adams 1986] This is rather puzzling. In what sense could a haecceity 'exist' to be referred to? Existence, but not as we know it, Jim. This smacks of medieval theology. |
| 13997 | Maybe Presentists can paraphrase singular propositions about the past [Markosian] |
| Full Idea: Maybe Presentists can paraphrase singular propositions about the past, into purely general past- and future-tensed sentences. | |
| From: Ned Markosian (A Defense of Presentism [2004], 3.5) | |
| A reaction: I'm not clear why Markosian worries about singular propositions, but is happy with general ones. Surely the latter refer as much as the former to what doesn't exist? Markosian objects that the paraphrase has a different meaning. |
| 13993 | Special Relativity denies the absolute present which Presentism needs [Markosian] |
| Full Idea: The objection to Presentism from Special Relativity is this: 1) Relativity is true, 2) so there is no absolute simultaneity, 3) so there is no absolute presentness, but 4) Presentism entails absolute presentness, so 5) Presentism is false. | |
| From: Ned Markosian (A Defense of Presentism [2004], 3.9) | |
| A reaction: I don't accept this objection. There may be accounts that can give Relativity one present (Idea 12689-90). Maybe Einstein was too instrumentalist in his account. Maybe we can have Presentism with multiple present moments. |
| 13998 | Objects in the past, like Socrates, are more like imaginary objects than like remote spatial objects [Markosian] |
| Full Idea: Maybe putative non-present objects like Socrates have more in common with putative non-actual objects like Santa Claus than they have in common with objects located elsewhere in space, like Alpha Centauri. | |
| From: Ned Markosian (A Defense of Presentism [2004], 3.7) | |
| A reaction: We can see Alpha Centauri, so we need an example beyond some 'event horizon'. He credits Arthur Prior with this line of thought. He seems to me to drift towards a Descriptive Theory of Reference (shock!). Does the nature of reference change with death? |
| 13999 | People are mistaken when they think 'Socrates was a philosopher' says something [Markosian] |
| Full Idea: People sometimes think that 'Socrates was a philosopher' expresses something like a true, singular proposition about Socrates. They're making a mistake, but still, this explains why they think it is true. | |
| From: Ned Markosian (A Defense of Presentism [2004], 3.8) | |
| A reaction: A classic error theory, about our talk of the past. Personally I would say that the sentence really is true, and that needing a tangible object to refer to is a totally bogus requirement. 'I wonder if there are any scissors in the house?' |
| 20911 | There are unlimited worlds of varying sizes, some without life or water [Democritus, by Hippolytus] |
| Full Idea: Democritus says that there exist unlimited worlds and that they are different in magnitude. ...Some worlds are devoid of animals and plants and of all humidity. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A010, A040) by Hippolytus - Refutation of All Heresies 1.12,13.2-4 | |
| A reaction: I'm not clear why Democritus came up with the idea of the Multicosmos. I don't suppose he meant the moon or planets, but another Cosmos. |
| 1535 | Democritus said people imagined gods as the source of what awed or frightened them [Democritus, by Sext.Empiricus] |
| Full Idea: Democritus thought that people imagined gods as responsible for the frightening and awesome things that happen in this world. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A075) by Sextus Empiricus - Against the Professors (six books) 9.24 |
| 20915 | The soul is destroyed with the body [Democritus, by Ps-Plutarch] |
| Full Idea: Democritus says the soul is destructible, and is destroyed together with the whole body. | |
| From: report of Democritus (fragments/reports [c.431 BCE], A109) by Pseudo-Plutarch - On the Doctrine of the Philosophers 4.7.4 | |
| A reaction: This is the only belief possible for Democritus, since everything, including life and soul, is just the confluence of atoms, and they are regularly dispersed. This is the epitome of materialist philosophy. |