Combining Philosophers

All the ideas for Anaxarchus, Dale Jacquette and Parmenides

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59 ideas

2. Reason / A. Nature of Reason / 1. On Reason
Parmenides was much more cautious about accepting ideas than his predecessors [Simplicius on Parmenides]
     Full Idea: Parmenides would not agree with anything unless it seemed necessary, whereas his predecessors used to come up with unsubstantiated assertions.
     From: comment on Parmenides (fragments/reports [c.474 BCE], A28) by Simplicius - On Aristotle's 'Physics' 9.116.2-
     A reaction: from Eudemus
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / a. Systems of modal logic
Modal logic is multiple systems, shown in the variety of accessibility relations between worlds [Jacquette]
     Full Idea: Modal logic by its very nature is not monolithic, but fragmented into multiple systems of modal qualifications, reflected in the plurality of accessibility relations on modal model structures or logically possible worlds.
     From: Dale Jacquette (Intro to 'Philosophy of Logic' [2002], §3)
     A reaction: He implies the multiplicity is basic, and is only 'reflected' in the relations, but maybe the multiplicity is caused by incompetent logicians who can't decide whether possible worlds really are reflexive or symmetrical or transitive in their relations.
4. Formal Logic / D. Modal Logic ML / 4. Alethic Modal Logic
The modal logic of C.I.Lewis was only interpreted by Kripke and Hintikka in the 1960s [Jacquette]
     Full Idea: The modal syntax and axiom systems of C.I.Lewis (1918) were formally interpreted by Kripke and Hintikka (c.1965) who, using Z-F set theory, worked out model set-theoretical semantics for modal logics and quantified modal logics.
     From: Dale Jacquette (Ontology [2002], Ch. 2)
     A reaction: A historical note. The big question is always 'who cares?' - to which the answer seems to be 'lots of people', if they are interested in precision in discourse, in artificial intelligence, and maybe even in metaphysics. Possible worlds started here.
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
The two main views in philosophy of logic are extensionalism and intensionalism [Jacquette]
     Full Idea: Philosophy of logic has (roughly) two camps: extensionalists and intensionalists, with the former view dominant. ...There is a close connection between this and eliminativist or reductivist versus folk psychological and intentionalist philosophy of mind.
     From: Dale Jacquette (Intro to 'Philosophy of Logic' [2002], §4)
     A reaction: Hm. I think I favour intensionalism in the logic, and reductivism about the mind, so I may have a bit of bother here. I'm convinced that this jigsaw can be completed, despite all appearances.
Logic describes inferences between sentences expressing possible properties of objects [Jacquette]
     Full Idea: It is fundamental that logic depends on logical possibilities, in which logically possible properties are predicated of logically possible objects. Logic describes inferential structures among sentences expressing the predication of properties to objects.
     From: Dale Jacquette (Ontology [2002], Ch. 2)
     A reaction: If our imagination is the only tool we have for assessing possibilities, this leaves the domain of logic as being a bit subjective. There is an underlying Platonism to the idea, since inferences would exist even if nothing else did.
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
Classical logic is bivalent, has excluded middle, and only quantifies over existent objects [Jacquette]
     Full Idea: Classical logic (of Whitehead, Russell, Gödel, Church) is a two-valued system of propositional and predicate logic, in which all propositions are exclusively true or false, and quantification and predication are over existent objects only.
     From: Dale Jacquette (Intro to I: Classical Logic [2002], p.9)
     A reaction: All of these get challenged at some point, though the existence requirement is the one I find dubious.
5. Theory of Logic / C. Ontology of Logic / 2. Platonism in Logic
Logic is not just about signs, because it relates to states of affairs, objects, properties and truth-values [Jacquette]
     Full Idea: At one level logic can be regarded as a theory of signs and formal rules, but we cannot neglect the meaning of propositions as they relate to states of affairs, and hence to possible properties and objects... there must be the possibility of truth-values.
     From: Dale Jacquette (Ontology [2002], Ch. 2)
     A reaction: Thus if you define logical connectives by truth tables, you need the concept of T and F. You could, though, regard those too as purely formal (like 1 and 0 in electronics). But how do you decide which propositions are 1, and which are 0?
5. Theory of Logic / F. Referring in Logic / 2. Descriptions / c. Theory of definite descriptions
On Russell's analysis, the sentence "The winged horse has wings" comes out as false [Jacquette]
     Full Idea: It is infamous that on Russell's analysis the sentences "The winged horse has wings" and "The winged horse is a horse" are false, because in the extant domain of actual existent entities there contingently exist no winged horses
     From: Dale Jacquette (Ontology [2002], Ch. 6)
     A reaction: This is the best objection I have heard to Russell's account of definite descriptions. The connected question is whether 'quantifies over' is really a commitment to existence. See Idea 6067.
5. Theory of Logic / G. Quantification / 4. Substitutional Quantification
Substitutional universal quantification retains truth for substitution of terms of the same type [Jacquette]
     Full Idea: The substitutional interpretation says the universal quantifier is true just in case it remains true for all substitutions of terms of the same type as that of the universally bound variable.
     From: Dale Jacquette (Intro to III: Quantifiers [2002], p.143)
     A reaction: This doesn't seem to tell us how it gets started with being true.
Nominalists like substitutional quantification to avoid the metaphysics of objects [Jacquette]
     Full Idea: Some substitutional quantificationists in logic hope to avoid philosophical entanglements about the metaphysics of objects, ..and nominalists can find aid and comfort there.
     From: Dale Jacquette (Intro to III: Quantifiers [2002], p.143)
     A reaction: This has an appeal for me, particularly if it avoids abstract objects, but I don't see much problem with material objects, so we might as well have a view that admits those.
5. Theory of Logic / I. Semantics of Logic / 5. Extensionalism
Extensionalists say that quantifiers presuppose the existence of their objects [Jacquette]
     Full Idea: Extensionalists hold that quantifiers in predicate logic presuppose the existence of whatever objects can be referred to by constants or bound variables, or enter into true predication of properties.
     From: Dale Jacquette (Intro to 'Philosophy of Logic' [2002], §4)
     A reaction: I have strong sales resistance to this view. Why should a procedure for correctly reasoning from one proposition to another have anything whatever to do with ontology? A false world picture can be interconnected by perfect logic.
5. Theory of Logic / I. Semantics of Logic / 6. Intensionalism
Intensionalists say meaning is determined by the possession of properties [Jacquette]
     Full Idea: According to intensionalist semantics the meaning of a proposition is determined by the properties an object possesses.
     From: Dale Jacquette (Intro to 'Philosophy of Logic' [2002], §4)
     A reaction: This sounds good to me. Extensionalist don't seem to care what sets they put things in, but if property possession comes first, then things will fall into their own sets without any help for us. We can add silly sets afterwards, if we fancy.
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / d. Russell's paradox
Can a Barber shave all and only those persons who do not shave themselves? [Jacquette]
     Full Idea: The Barber Paradox refers to the non-existent property of being a barber who shaves all and only those persons who do not shave themselves.
     From: Dale Jacquette (Ontology [2002], Ch. 9)
     A reaction: [Russell spotted this paradox, and it led to his Theory of Types]. This paradox may throw light on the logic of indexicals. What does "you" mean when I say to myself "you idiot!"? If I can behave as two persons, so can the barber.
7. Existence / A. Nature of Existence / 3. Being / a. Nature of Being
To grasp being, we must say why something exists, and why there is one world [Jacquette]
     Full Idea: We grasp the concept of being only when we have satisfactorily answered the question why there is something rather than nothing and why there is only one logically contingent actual world.
     From: Dale Jacquette (Ontology [2002], Conclusion)
     A reaction: See Ideas 7688 and 7692 for a glimpse of Jacquette's answer. Personally I don't yet have a full grasp of the concept of being, but I'm sure I'll get there if I only work a bit harder.
No necessity could produce Being either later or earlier, so it must exist absolutely or not at all [Parmenides]
     Full Idea: What necessity impelled Being, if it did spring from nothing, to be produced later or earlier? Thus it must be absolutely, or not at all.
     From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1-
Being must be eternal and uncreated, and hence it is timeless [Parmenides]
     Full Idea: Being has no coming-to-be and no destruction, for it is whole of limb, without motion, and without end. And it never was, nor will be, because it is now, a whole all together, one, continuous; for what creation of it will you look for?
     From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1-
Being is not divisible, since it is all alike [Parmenides]
     Full Idea: Being is not divisible, since it is all alike.
     From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1-
7. Existence / A. Nature of Existence / 3. Being / d. Non-being
The realm of necessary non-existence cannot be explored, because it is unknowable [Parmenides]
     Full Idea: The other way of enquiry, that IT IS NOT, and IT is bound NOT TO BE, cannot be explored, for you could neither recognise nor express that which IS NOT.
     From: Parmenides (fragments/reports [c.474 BCE], B02), quoted by Simplicius - On Aristotle's 'Physics' 9.116.28-
There is no such thing as nothing [Parmenides]
     Full Idea: There is no such thing as nothing.
     From: Parmenides (fragments/reports [c.474 BCE], B06), quoted by Simplicius - On Aristotle's 'Physics' 9.86.27-
7. Existence / A. Nature of Existence / 3. Being / f. Primary being
Parmenides at least saw Being as the same as Nous, and separate from the sensed realm [Parmenides, by Plotinus]
     Full Idea: Parmenides made some approach to the doctrine of Plato in identifying Being with Intellectual-Principle [Nous] while separating Real Being from the realm of sense.
     From: report of Parmenides (fragments/reports [c.474 BCE]) by Plotinus - The Enneads 5.1.08
     A reaction: The point is that for Parmenides the One is the essence of Being, but for platonists there is something prior to and higher than Being. For Plato it is the Good; for Plotinus it is a revised (non-Being) concept of the One.
7. Existence / A. Nature of Existence / 5. Reason for Existence
Being is maximal consistency [Jacquette]
     Full Idea: Being is maximal consistency.
     From: Dale Jacquette (Ontology [2002], Ch. 2)
     A reaction: You'll have to read Ch.2 of Jacquette to see what this is all about, but as it stands it is a lovely slogan, and a wonderful googly/curve ball to propel at Parmenides or Heidegger.
Existence is completeness and consistency [Jacquette]
     Full Idea: A combinatorial ontology holds that existence is nothing more or less than completeness and consistency, or what is also called 'maximal consistency'.
     From: Dale Jacquette (Ontology [2002], Ch. 2)
     A reaction: You'll have to read Jacquette to understand this one! The claim is that existence is to be defined in terms of logic (and whatever is required for logic). I take this to be a bit Platonist (rather than conventionalist) about logic.
7. Existence / B. Change in Existence / 1. Nature of Change
All our concepts of change and permanence are just names, not the truth [Parmenides]
     Full Idea: All things that mortals have established, believing in their truth, are just a name: Becoming and Perishing, Being and Not-Being, and change of position, and alteration of bright colour.
     From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1-
7. Existence / D. Theories of Reality / 1. Ontologies
Ontology is the same as the conceptual foundations of logic [Jacquette]
     Full Idea: The principles of pure philosophical ontology are indistinguishable ... from the conceptual foundations of logic.
     From: Dale Jacquette (Ontology [2002], Pref)
     A reaction: I would take Russell to be an originator of this view. If the young Wittgenstein showed that the foundations of logic are simply conventional (truth tables), this seems to make ontology conventional too, which sounds very odd indeed (to me).
7. Existence / D. Theories of Reality / 11. Ontological Commitment / a. Ontological commitment
Ontology must include the minimum requirements for our semantics [Jacquette]
     Full Idea: The entities included in a theoretical ontology are those minimally required for an adequate philosophical semantics. ...These are the objects that we say exist, to which we are ontologically committed.
     From: Dale Jacquette (Ontology [2002], Pref)
     A reaction: Worded with exquisite care! He does not say that ontology is reducible to semantics (which is a silly idea). We could still be committed, as in a ghost story, to existence of some 'nameless thing'. Things utterly beyond our ken might exist.
7. Existence / E. Categories / 3. Proposed Categories
Logic is based either on separate objects and properties, or objects as combinations of properties [Jacquette]
     Full Idea: Logic involves the possibilities of predicating properties of objects in a conceptual scheme wherein either objects and properties are included in altogether separate categories, or objects are reducible to combinations of properties.
     From: Dale Jacquette (Ontology [2002], Ch. 2)
     A reaction: In the first view, he says that objects are just 'logical pegs' for properties. Objects can't be individuated without properties. But combinations of properties would seem to need essences, or else they are too unstable to count as objects.
Reduce states-of-affairs to object-property combinations, and possible worlds to states-of-affairs [Jacquette]
     Full Idea: We can reduce references to states-of-affairs to object-property combinations, and we can reduce logically possible worlds to logically possible states-of-affairs combinations.
     From: Dale Jacquette (Ontology [2002], Ch. 2)
     A reaction: If we further reduce object-property combinations to mere combinations of properties (Idea 7683), then we have reduced our ontology to nothing but properties. Wow. We had better be very clear, then, about what a property is. I'm not.
8. Modes of Existence / B. Properties / 11. Properties as Sets
If classes can't be eliminated, and they are property combinations, then properties (universals) can't be either [Jacquette]
     Full Idea: If classes alone cannot be eliminated from ontology on Quine's terms, and if classes are defined as property combinations, then neither are all properties, universals in the tradition sense, entirely eliminable.
     From: Dale Jacquette (Ontology [2002], Ch. 9)
     A reaction: If classes were totally conventional (and there was no such things as a 'natural' class) then you might admit something to a class without knowing its properties (as 'the thing in the box').
9. Objects / A. Existence of Objects / 1. Physical Objects
An object is a predication subject, distinguished by a distinctive combination of properties [Jacquette]
     Full Idea: To be an object is to be a predication subject, and to be this as opposed to that particular object, whether existent or not, is to have a distinctive combination of properties.
     From: Dale Jacquette (Ontology [2002], Ch. 2)
     A reaction: The last part depends on Leibniz's Law. The difficulty is that two objects may only be distinguishable by being in different places, and location doesn't look like a property. Cf. Idea 5055.
9. Objects / A. Existence of Objects / 2. Abstract Objects / c. Modern abstracta
Numbers, sets and propositions are abstract particulars; properties, qualities and relations are universals [Jacquette]
     Full Idea: Roughly, numbers, sets and propositions are assumed to be abstract particulars, while properties, including qualities and relations, are usually thought to be universals.
     From: Dale Jacquette (Ontology [2002], Ch. 9)
     A reaction: There is an interesting nominalist project of reducing all of these to particulars. Numbers to patterns, sets to their members, propositions to sentences, properties to causal powers, relations to, er, something else.
9. Objects / E. Objects over Time / 1. Objects over Time
Something must be unchanging to make recognition and knowledge possible [Aristotle on Parmenides]
     Full Idea: Parmenides and Melissus were the first to appreciate that there must be unchanging entities, if recognition and knowledge are to exist.
     From: comment on Parmenides (fragments/reports [c.474 BCE], A25) by Aristotle - On the Heavens 298b14
10. Modality / A. Necessity / 5. Metaphysical Necessity
The first way of enquiry involves necessary existence [Parmenides]
     Full Idea: The first way of enquiry is the one that IT IS, and it is not possible for IT NOT TO BE, which is the way of credibility, for it follows truth.
     From: Parmenides (fragments/reports [c.474 BCE], B02), quoted by Simplicius - On Aristotle's 'Physics' 9.116.28-
     A reaction: also Proclus 'Timeus'
10. Modality / A. Necessity / 8. Transcendental Necessity
Necessity sets limits on being, in order to give it identity [Parmenides]
     Full Idea: Powerful necessity holds Being in the bonds of a limit, which constrains it round about, because divine law decrees that Being shall not be without boundary. For it is not lacking, but if it were spatially infinite, it would lack everything.
     From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1-
10. Modality / E. Possible worlds / 1. Possible Worlds / a. Possible worlds
The actual world is a consistent combination of states, made of consistent property combinations [Jacquette]
     Full Idea: The actual world is a maximally consistent state-of-affairs combination involving all and only the existent objects, which in turn exist because they are maximally consistent property combinations.
     From: Dale Jacquette (Ontology [2002], Ch. 2)
     A reaction: [This extends Idea 7688]. This seems to invite the standard objections to the coherence theory of truth, such as Ideas 5422 and 4745. Is 'maximal consistency' merely a test for actuality, rather than an account of what actuality is?
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / a. Nature of possible worlds
The actual world is a maximally consistent combination of actual states of affairs [Jacquette]
     Full Idea: The actual world can be defined as a maximally consistent combination of actual states of affairs, or maximally consistent states-of-affairs combination.
     From: Dale Jacquette (Ontology [2002], Ch. 2)
     A reaction: A key part of Jacquette's program of deriving ontological results from the foundations of logic. Is the counterfactual situation of my pen being three centimetres to the left of its current position a "less consistent" situation than the actual one?
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / c. Worlds as propositions
Do proposition-structures not associated with the actual world deserve to be called worlds? [Jacquette]
     Full Idea: Many modal logicians in their philosophical moments have raised doubts about whether structures of propositions not associated with the actual world deserved to be called worlds at all.
     From: Dale Jacquette (Ontology [2002], Ch. 2)
     A reaction: A good question. Consistency is obviously required, but we also need a lot of propositions before we would consider it a 'world'. Very remote but consistent worlds quickly become unimaginable. Does that matter?
We must experience the 'actual' world, which is defined by maximally consistent propositions [Jacquette]
     Full Idea: Conventional modal semantics, in which all logically possible worlds are defined in terms of maximally consistent proposition sets, has no choice except to allow that the actual world is the world we experience in sensation, or that we inhabit.
     From: Dale Jacquette (Ontology [2002], Ch. 9)
     A reaction: Jacquette dislikes this because he is seeking an account of ontology that doesn't, as so often, merely reduce to epistemology (e.g. Berkeley). See Idea 7691 for his preferred account.
11. Knowledge Aims / B. Certain Knowledge / 4. The Cogito
Thinking implies existence, because thinking depends on it [Parmenides]
     Full Idea: To think is the same as the thought that IT IS, for you will not find thinking without Being, on which it depends for its expression.
     From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1-
12. Knowledge Sources / B. Perception / 1. Perception
Parmenides treats perception and intellectual activity as the same [Theophrastus on Parmenides]
     Full Idea: Parmenides treats perception and intellectual activity as the same.
     From: comment on Parmenides (fragments/reports [c.474 BCE], A46) by Theophrastus - On the Senses 3.1
     A reaction: cf Theaetetus pt 1
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Only reason can prove the truth of facts [Parmenides]
     Full Idea: Reason alone will prove the truth of facts.
     From: Parmenides (fragments/reports [c.474 BCE]), quoted by Diogenes Laertius - Lives of Eminent Philosophers 09.3.3
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
Anaxarchus said that he was not even sure that he knew nothing [Anaxarchus, by Diog. Laertius]
     Full Idea: Anaxarchus said that he was not even sure that he knew nothing.
     From: report of Anaxarchus (fragments/reports [c.340 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.10.1
15. Nature of Minds / B. Features of Minds / 5. Qualia / c. Explaining qualia
If qualia supervene on intentional states, then intentional states are explanatorily fundamental [Jacquette]
     Full Idea: If qualia supervene on intentional states, then intentionality is also more explanatorily fundamental than qualia.
     From: Dale Jacquette (Ontology [2002], Ch.10)
     A reaction: See Idea 7272 for opposite view. Maybe intentional states are large mental objects of which we are introspectively aware, but which are actually composed of innumerable fine-grained qualia. Intentional states would only explain qualia if they caused them.
17. Mind and Body / E. Mind as Physical / 2. Reduction of Mind
Reduction of intentionality involving nonexistent objects is impossible, as reduction must be to what is actual [Jacquette]
     Full Idea: If intentionality sometimes involves a relation to nonexistent objects, like my dreamed-of visit to a Greek island, then such thoughts cannot be explained physically or causally, because only actual physical entities and events can be mentioned.
     From: Dale Jacquette (Ontology [2002], Ch.10)
     A reaction: Unimpressive. Thoughts of a Greek island will obviously reduce to memories of islands and Greece and travel brochures. Memory clearly retains past events in the present, and hence past events can be part of the material used in reductive accounts.
19. Language / C. Assigning Meanings / 7. Extensional Semantics
Extensionalist semantics forbids reference to nonexistent objects [Jacquette]
     Full Idea: In extensionalist semantics only existent objects can be referred to, ...but in everyday thought and discourse we regularly and apparently without undue confusion speak about nonexistent objects.
     From: Dale Jacquette (Intro to 'Philosophy of Logic' [2002], §4)
     A reaction: This is the reason why Meinong, whose views are presented by Russell as absurd, are undergoing a revival. The full-blown view will even treat 'round squares' as objects about which we can reason - and why not? Don't open a shop which sells them.
Extensionalist semantics is circular, as we must know the extension before assessing 'Fa' [Jacquette]
     Full Idea: Extensional semantics is blatantly circular. For 'Fa' to be interpreted as true, we must know that object a belongs to the extension of the predicate F, so we must already know which objects belong to the extension.
     From: Dale Jacquette (Intro to 'Philosophy of Logic' [2002], §4)
     A reaction: I'm delighted to read this, because it was the first thought that occurred to me when I encountered the theory. Presumably this leads Quine to take predication as basic, because you can't break into the circle. Or, vote for intensionalism?
19. Language / D. Propositions / 1. Propositions
The extreme views on propositions are Frege's Platonism and Quine's extreme nominalism [Jacquette]
     Full Idea: The extreme ontological alternatives with respect to the metaphysics of propositions are a Fregean Platonism (his "gedanken", 'thoughts'), and a radical nominalism or inscriptionalism, as in Quine, where they are just marks related to stimuli.
     From: Dale Jacquette (Ontology [2002], Ch. 9)
     A reaction: Personally I would want something between the two - that propositions are brain events of a highly abstract kind. I say that introspection reveals pre-linguistic thoughts, which are propositions. A proposition is an intentional state.
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / e. The One
The one is without any kind of motion [Parmenides]
     Full Idea: The one is without any kind of motion.
     From: Parmenides (fragments/reports [c.474 BCE]), quoted by Plato - Parmenides 139a
People who say that the cosmos is one forget that they must explain movement [Aristotle on Parmenides]
     Full Idea: Those who assert that the universe is one and a single nature, when they try to give the causes of generation and destruction, miss out the cause of movement.
     From: comment on Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Metaphysics 988b
There could be movement within one thing, as there is within water [Aristotle on Parmenides]
     Full Idea: Why does it follow from there being only one thing that it is unmoving, since, for example, water moves internally while remaining one?
     From: comment on Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Physics 186a16
     A reaction: One suspects that Parmenides wasn't used to critical questions like this, and would have sharpened up his theory if it had been subjected to criticism. How big was the One? Maybe Aristotle is the real father of philosophy.
The one can't be divisible, because if it was it could be infinitely divided down to nothing [Parmenides, by Simplicius]
     Full Idea: Since the one is everywhere alike, then if it is divisible, it will be equally divisible everywhere….so let it be divided everywhere. It is obvious that nothing will remain and the whole will vanish, and so (if it is compound) it is composed of nothing.
     From: report of Parmenides (fragments/reports [c.474 BCE]) by Simplicius - On Aristotle's 'Physics' 9.139.5-
     A reaction: he is quoting Porphyry
Defenders of the One say motion needs the void - but that is not part of Being [Parmenides, by Aristotle]
     Full Idea: Defenders of the One say that there could not be motion without a void, and that void is what does not exist, and that nothing that is not belongs to being.
     From: report of Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 325a26
     A reaction: This is why motion is an illusion, a view also supported by the paradoxes of Zeno of Elea. Aristotle goes on to give Democritus's response to this idea. Parmenides was contemplating 'void', before Democritus got to it.
Reason sees reality as one, the senses see it as many [Aristotle on Parmenides]
     Full Idea: Since he is forced to be guided by appearances, he assumes that the one exists from the viewpoint of reason, but that a plurality exists from the viewpoint of the sense, and so he posits two principles and causes - hot and cold.
     From: comment on Parmenides (fragments/reports [c.474 BCE], A24) by Aristotle - Metaphysics 986b27-
     A reaction: A profound thought. Empiricists emphasies experience, and end up with fragmented reality. Reason explains experience, and in the process sees the world as unities (like objects), though a single unity is going too far.
Reality is symmetrical and balanced, like a sphere, with no reason to be greater one way rather than another [Parmenides]
     Full Idea: Since there is a spatial limit, it is complete on every side, like the mass of a well-rounded sphere, equally balanced from its centre in every direction; for it is not bound to be at all either greater or less in this direction or that.
     From: Parmenides (fragments/reports [c.474 BCE], B08 ll.?), quoted by Simplicius - On Aristotle's 'Physics' 9.145.1-
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / f. Ancient elements
He taught that there are two elements, fire the maker, and earth the matter [Parmenides, by Diog. Laertius]
     Full Idea: He taught that there were two elements, fire and earth; and that one of them occupies the place of the maker, the other that of the matter.
     From: report of Parmenides (fragments/reports [c.474 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Pa.2
27. Natural Reality / A. Classical Physics / 1. Mechanics / a. Explaining movement
It is feeble-minded to look for explanations of everything being at rest [Aristotle on Parmenides]
     Full Idea: For people to ignore the evidence of their senses and look for an explanation for everything being at rest is feeble-minded.
     From: comment on Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Physics 253a32
     A reaction: Not exactly an argument, but an interestingly robust assertion of commonsense against dodgy arguments. Aristotle is not exactly an empiricist, but he is on that side of the fence.
27. Natural Reality / C. Space / 1. Void
The void can't exist, and without the void there can't be movement or separation [Parmenides, by Aristotle]
     Full Idea: Some philosophers thought what is must be one and immovable. The void, they say, is not: but unless there is a void what is cannot be moved, nor can it be many, since there is nothing to keep things apart.
     From: report of Parmenides (fragments/reports [c.474 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 325a06
     A reaction: Somehow this doesn't seem very persuasive any more! I suppose we would distinguish various degrees of void, and assert the existence of sufficient void to allow movement and separation. We must surely agree that total nothingness doesn't exist.
27. Natural Reality / D. Time / 3. Parts of Time / a. Beginning of time
What could have triggered the beginning [of time and being]? [Parmenides]
     Full Idea: What need would have aroused it later or sooner, starting from nothing to come into being?
     From: Parmenides (fragments/reports [c.474 BCE]), quoted by Robin Le Poidevin - Travels in Four Dimensions 02 'Everything'
     A reaction: [Barnes 1982:178] This remains an excellent question. The last I heard was a 'quantum fluctuation', but that seems to be an event, which therefore needs time.
27. Natural Reality / E. Cosmology / 1. Cosmology
He was the first person to say the earth is spherical [Parmenides, by Diog. Laertius]
     Full Idea: He was the first person who asserted that the earth was of a spherical form.
     From: report of Parmenides (fragments/reports [c.474 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Pa.2
He was the first to discover the identity of the Morning and Evening Stars [Parmenides, by Diog. Laertius]
     Full Idea: He appears to have been the first to discover that Hesperus and Lucifer were the same star.
     From: report of Parmenides (fragments/reports [c.474 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.Pa.3
     A reaction: This is the famous example used by Frege to discuss reference and meaning.