Combining Texts

All the ideas for 'The Nature of Things', 'On Freedom' and 'fragments/reports'

unexpand these ideas     |    start again     |     specify just one area for these texts


17 ideas

4. Formal Logic / F. Set Theory ST / 7. Natural Sets
A class is natural when everybody can spot further members of it [Quinton]
     Full Idea: To say that a class is natural is to say that when some of its members are shown to people they pick out others without hesitation and in agreement.
     From: Anthony Quinton (The Nature of Things [1973], 9 'Nat')
     A reaction: He concedes a number of problems with his view, but I admire his attempt to at least begin to distinguish the natural (real!) classes from the ersatz ones. A mention of causal powers would greatly improve his story.
5. Theory of Logic / L. Paradox / 4. Paradoxes in Logic / a. Achilles paradox
We don't have time for infinite quantity, but we do for infinite divisibility, because time is also divisible [Aristotle on Zeno of Elea]
     Full Idea: Although it is impossible to make contact in a finite time with things that are infinite in quantity, it is possible to do so with things that are infinitely divisible, since the time itself is also infinite in this way.
     From: comment on Zeno (Elea) (fragments/reports [c.450 BCE], A25) by Aristotle - Physics 233a21
The fast runner must always reach the point from which the slower runner started [Zeno of Elea, by Aristotle]
     Full Idea: Zeno's so-called 'Achilles' claims that the slowest runner will never be caught by the fastest runner, because the one behind has first to reach the point from which the one in front started, and so the slower one is bound always to be in front.
     From: report of Zeno (Elea) (fragments/reports [c.450 BCE]) by Aristotle - Physics 239b14
     A reaction: The point is that the slower runner will always have moved on when the faster runner catches up with the starting point. We must understand how humble the early Greeks felt when they confronted arguments like this. It was like a divine revelation.
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / b. The Heap paradox ('Sorites')
Zeno is wrong that one grain of millet makes a sound; why should one grain achieve what the whole bushel does? [Aristotle on Zeno of Elea]
     Full Idea: Zeno is wrong in arguing that the tiniest fragment of millet makes a sound; there is no reason why the fragment should be able to move in any amount of time the air which the whole bushel moved as it fell.
     From: comment on Zeno (Elea) (fragments/reports [c.450 BCE], A29) by Aristotle - Physics 250a16
5. Theory of Logic / L. Paradox / 7. Paradoxes of Time
Zeno's arrow paradox depends on the assumption that time is composed of nows [Aristotle on Zeno of Elea]
     Full Idea: Zeno's third argument claims that a moving arrow is still. Here the conclusion depends on assuming that time is composed of nows; if this assumption is not granted, the argument fails.
     From: comment on Zeno (Elea) (fragments/reports [c.450 BCE], A27?) by Aristotle - Physics 239b5
7. Existence / E. Categories / 5. Category Anti-Realism
Extreme nominalists say all classification is arbitrary convention [Quinton]
     Full Idea: Pure, extreme nominalism sees all classification as the product of arbitrary convention.
     From: Anthony Quinton (The Nature of Things [1973], 9 'Nat')
     A reaction: I'm not sure what the word 'arbitrary' is doing there. Nominalists are not daft, and if they can classify any way they like, they are not likely to choose an 'arbitrary' system. Pragmatism tells the right story here.
8. Modes of Existence / B. Properties / 5. Natural Properties
The naturalness of a class depends as much on the observers as on the objects [Quinton]
     Full Idea: The naturalness of a class depends as essentially on the nature of the observers who classify as it does on the nature of the objects that they classify. ...It depends on our perceptual apparatus, and on our relatively mutable needs and interests.
     From: Anthony Quinton (The Nature of Things [1973], 9 'Nat')
     A reaction: This seems to translate 'natural' as 'natural for us', which is not much use to scientists, who spend quite a lot of effort combating folk wisdom. Do desirable sports cars constitute a natural class?
Properties imply natural classes which can be picked out by everybody [Quinton]
     Full Idea: To say there are properties is to say there are natural classes, classes introduction to some of whose members enables people to pick out others without hesitation and in agreement.
     From: Anthony Quinton (The Nature of Things [1973], 9 'Nat')
     A reaction: Aristotle would like this approach, but it doesn't find many friends among modern logician/philosophers. We should go on to ask why people agree on these things. Causal powers will then come into it.
8. Modes of Existence / D. Universals / 4. Uninstantiated Universals
Uninstantiated properties must be defined using the instantiated ones [Quinton]
     Full Idea: Properties that have no concrete instances must be defined in terms of those that have.
     From: Anthony Quinton (The Nature of Things [1973], 9 'Nat')
     A reaction: I wonder what the dodo used to smell like?
9. Objects / A. Existence of Objects / 5. Individuation / b. Individuation by properties
An individual is a union of a group of qualities and a position [Quinton, by Campbell,K]
     Full Idea: Quinton proposes that an individual is a union of a group of qualities and a position.
     From: report of Anthony Quinton (The Nature of Things [1973], Pt I) by Keith Campbell - The Metaphysic of Abstract Particulars §5
     A reaction: This seems the obvious defence of a bundle account of objects against the charge that indiscernibles would have to be identical. It introduces, however, 'positions' into the ontology, but maybe that price must be paid. Materialism needs space.
10. Modality / B. Possibility / 5. Contingency
Necessary truths can be analysed into original truths; contingent truths are infinitely analysable [Leibniz]
     Full Idea: Derivative truths are of two sorts: some are analysed into original truths, others admit of an infinite process of analysis. The former are necessary, the latter are contingent.
     From: Gottfried Leibniz (On Freedom [1689], p.108)
     A reaction: An intriguing proposal. Hume would presumably see contingent truths as being analysed until you reach 'impressions'. Analysis of necessary truths soon comes to the blinding light of what is obvious, but analysis of contingency never gets there.
10. Modality / D. Knowledge of Modality / 2. A Priori Contingent
Only God sees contingent truths a priori [Leibniz]
     Full Idea: Only God sees contingent truths a priori.
     From: Gottfried Leibniz (On Freedom [1689], p.95)
     A reaction: This because everything is interconnected, and the whole picture must be seen to understand a contingent truth.
10. Modality / E. Possible worlds / 3. Transworld Objects / e. Possible Objects
If non-existents are possible, their existence would replace what now exists, which cannot therefore be necessary [Leibniz]
     Full Idea: If certain possibles never exist, then existing things are not always necessary; otherwise it would be impossible for other things to exist instead of them, and so all things that never exist would be impossible.
     From: Gottfried Leibniz (On Freedom [1689], p.106)
     A reaction: A neat argument, though it is not self-evident that when possibles came into existence they would have to replace what is already there. Can't something be possible, but only in another world, because this one is already booked?
26. Natural Theory / A. Speculations on Nature / 1. Nature
If there are many things they must have a finite number, but there must be endless things between them [Zeno of Elea]
     Full Idea: It things are many, they can't be more or less than they are, so they must be finite, but also there must be endless things between each thing, so they must be infinite.
     From: Zeno (Elea) (fragments/reports [c.450 BCE], B3), quoted by Simplicius - On Aristotle's 'Physics' 140.29
27. Natural Reality / A. Classical Physics / 1. Mechanics / a. Explaining movement
That which moves, moves neither in the place in which it is, nor in that in which it is not [Zeno of Elea]
     Full Idea: That which moves, moves neither in the place in which it is, nor in that in which it is not.
     From: Zeno (Elea) (fragments/reports [c.450 BCE], B4), quoted by (who?) - where?
27. Natural Reality / C. Space / 5. Relational Space
If everything is in a place, what is the place in? Place doesn't exist [Zeno of Elea, by Simplicius]
     Full Idea: If there is a place it will be in something, because everything that exists is in something. But what is in something is in a place. Therefore the place will be in a place, and so on ad infinitum. Therefore, there is no such thing as place.
     From: report of Zeno (Elea) (fragments/reports [c.450 BCE], B3) by Simplicius - On Aristotle's 'Physics' 9.562.3
28. God / A. Divine Nature / 3. Divine Perfections
God does everything in a perfect way, and never acts contrary to reason [Leibniz]
     Full Idea: We can regard it as certain that everything is done by God in the most perfect way, that he does nothing which is contrary to reason.
     From: Gottfried Leibniz (On Freedom [1689], p.109)
     A reaction: The famous optimism which Voltaire laughed at in 'Candide'. I can't help thinking that there is an ideal of God being ABOVE reason. We reason, and give reasons, because we are unsure, and life is a struggle. The highest ideal is mystically self-evident.