Combining Texts

All the ideas for 'The Nature of Things', 'Letters to Samuel Clarke' and 'Mental Files in Flux'

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29 ideas

2. Reason / B. Laws of Thought / 2. Sufficient Reason
The principle of sufficient reason is needed if we are to proceed from maths to physics [Leibniz]
     Full Idea: In order to proceed from mathematics to physics the principle of sufficient reason is necessary, that nothing happens without there being a reason why it should be thus rather than otherwise.
     From: Gottfried Leibniz (Letters to Samuel Clarke [1716], §2)
There is always a reason why things are thus rather than otherwise [Leibniz]
     Full Idea: Nothing happens without a sufficient reason why it should be thus rather than otherwise.
     From: Gottfried Leibniz (Letters to Samuel Clarke [1716], 3.2)
No reason could limit the quantity of matter, so there is no limit [Leibniz]
     Full Idea: There is no possible reason which could limit the quantity of matter; therefore there cannot in fact be any such limitation.
     From: Gottfried Leibniz (Letters to Samuel Clarke [1716], 4.21)
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 / A. Overview of Logic / 4. Pure Logic
A train of reasoning must be treated as all happening simultaneously [Recanati]
     Full Idea: For logic purposes, a train of reasoning has to be construed as synchronic.
     From: François Recanati (Mental Files in Flux [2016], 5.2)
     A reaction: If we are looking for a gulf between logic and the real world this is a factor to be considered, along with Nietzsche's observation about necessary simplification. [ref to Kaplan 'Afterthoughts' 1989, 584-5]
7. Existence / C. Structure of Existence / 6. Fundamentals / c. Monads
All simply substances are in harmony, because they all represent the one universe [Leibniz]
     Full Idea: All simple substances will always have a harmony among themselves, because they always represent the same universe.
     From: Gottfried Leibniz (Letters to Samuel Clarke [1716], V §91), quoted by Richard T.W. Arthur - Leibniz
     A reaction: We can accept that the universe itself does not contain contradictions (how could it), but it is a leap of faith to say that all monads represent the universe well enough to avoid contradictions. Maps can contradict one another.
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 / A. Relations / 1. Nature of Relations
The ratio between two lines can't be a feature of one, and cannot be in both [Leibniz]
     Full Idea: If the ratio of two lines L and M is conceived as abstracted from them both, without considering which is the subject and which the object, which will then be the subject? We cannot say both, for then we should have an accident in two subjects.
     From: Gottfried Leibniz (Letters to Samuel Clarke [1716], 5th Paper, §47), quoted by John Heil - Relations 'External'
     A reaction: [compressed] Leibniz is rejecting external relations as having any status in ontology. It looks like a mistake (originating in Aristotle) to try to shoehorn the ontology of relations into the substance-properties framework.
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.
18. Thought / A. Modes of Thought / 9. Indexical Thought
Indexicality is not just a feature of language; examples show it also occurs in thought [Recanati]
     Full Idea: People once took indexicality to be exclusively a property of language, ....but a series of examples seemed to establish that the thought expressed by uttering an indexical sentence is itself indexical (and is thus 'essential').
     From: François Recanati (Mental Files in Flux [2016], 6.1)
     A reaction: Perry's example of not realising it is him leaking the sugar in a supermarket is the best known example. Was this a key moment for realising that philosophy of thought is (pace Dummett) more important than philosophy of language?
How can we communicate indexical thoughts to people not in the right context? [Recanati]
     Full Idea: Indexical thoughts create an obvious problem with regard to communication. How can we manage to communicate such thoughts to those who are not in the right context?
     From: François Recanati (Mental Files in Flux [2016], 7.1)
     A reaction: One answer is that you often cannot communicate them. If I write on a wall 'I am here now', that doesn't tell the next passer-by very much. But 'it's raining here' said in a telephone call works fine - if you know the location of the caller.
18. Thought / B. Mechanics of Thought / 5. Mental Files
Mental files are concepts, which are either collections or (better) containers [Recanati]
     Full Idea: Mental files are entries in the mental encyclopedia, that is, concepts. Some, following Grice, say they are information collections, but I think of them as containers. Collections are determined by their elements, but containers have independent identity.
     From: François Recanati (Mental Files in Flux [2016], Pref)
     A reaction: [compressed] [Grice reference is 'Vacuous Names' (1969)] I agree with Recanati. The point is that you can invoke a file by a label, even when you don't know what the content is.
The Frege case of believing a thing is both F and not-F is explained by separate mental files [Recanati]
     Full Idea: Frege's Constraint says if a subject believes an object is both F and not-F (as in 'Frege cases'), then the subject thinks of that object under distinct modes of presentation. Having distinct mental files of the object is sufficient to generate this.
     From: François Recanati (Mental Files in Flux [2016], Pref)
     A reaction: [compressed] When you look at how many semantic puzzles (notably from Frege and Kripke) are solved by the existence of labelled mental files, the case for them is overwhelming.
19. Language / B. Reference / 4. Descriptive Reference / b. Reference by description
A linguistic expression refers to what its associated mental file refers to [Recanati]
     Full Idea: Mental files determine the reference of linguistic expressions: an expression refers to what the mental file associated with it refers to (at the time of tokening).
     From: François Recanati (Mental Files in Flux [2016], 5)
     A reaction: Invites the question of how mental files manage to refer, prior to the arrival of a linguistic expression. A mental file is usually fully of descriptions, but it might be no more than a label.
19. Language / D. Propositions / 4. Mental Propositions
There are speakers' thoughts and hearers' thoughts, but no further thought attached to the utterance [Recanati]
     Full Idea: There is the speaker's thought and the thought formed by the hearer. That is all there is. We don't need an additional entity, the thought expressed by the utterance.
     From: François Recanati (Mental Files in Flux [2016], 7.2)
     A reaction: This fits my view of propositions nicely. They are the two 'thoughts'. The notion of some further abstract 'proposition' with its own mode of independent existence strikes me as ontologically absurd.
19. Language / F. Communication / 5. Pragmatics / a. Contextual meaning
The Naive view of communication is that hearers acquire exactly the thoughts of the speaker [Recanati]
     Full Idea: The Naive Conception of Communication rests on the idea that communication is the replication of thoughts: the thought the hearer entertains when he understands what the speaker is saying is the very thought which the speaker expressed.
     From: François Recanati (Mental Files in Flux [2016], 7.1)
     A reaction: It is hard to believe that any modern thinker would believe such a view, given holistic views of language etc.
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / g. Atomism
The only simple things are monads, with no parts or extension [Leibniz]
     Full Idea: According to me there is nothing simple except true monads, which have no parts and no extensions.
     From: Gottfried Leibniz (Letters to Samuel Clarke [1716], 5.24)
Atomism is irrational because it suggests that two atoms can be indistinguishable [Leibniz]
     Full Idea: There are no two individuals indiscernible from one another - leaves, or drops of water, for example. This is an argument against atoms, which, like the void, are opposed to the principles of a true metaphysic.
     From: Gottfried Leibniz (Letters to Samuel Clarke [1716], 4.04)
Things are infinitely subdivisible and contain new worlds, which atoms would make impossible [Leibniz]
     Full Idea: The least corpuscle is actually subdivided ad infinitum and contains a world of new created things, which this universe would lack if this corpuscle were an atom.
     From: Gottfried Leibniz (Letters to Samuel Clarke [1716], 4.PS)
27. Natural Reality / A. Classical Physics / 2. Thermodynamics / c. Conservation of energy
Leibniz upheld conservations of momentum and energy [Leibniz, by Papineau]
     Full Idea: In place of Descartes's conservation of 'quantity of motion', Leibniz upheld both the conservation of linear momentum and the conservation of kinetic energy.
     From: report of Gottfried Leibniz (Letters to Samuel Clarke [1716], 5th paper) by David Papineau - Thinking about Consciousness App 2
     A reaction: The point is that momentum involves velocity (which includes direction) rather than speed. Leibniz more or less invented the concept of 'energy' ('vis viva'). Papineau says these two leave no room for causation by mental substance.
27. Natural Reality / C. Space / 4. Substantival Space
The idea that the universe could be moved forward with no other change is just a fantasy [Leibniz]
     Full Idea: To say that God could cause the universe to move forward in a straight line or otherwise without changing it in any other way is another fanciful supposition.
     From: Gottfried Leibniz (Letters to Samuel Clarke [1716], 4.14)
27. Natural Reality / D. Time / 1. Nature of Time / b. Relative time
Space and time are purely relative [Leibniz]
     Full Idea: I have more than once stated that I held space to be something purely relative, like time.
     From: Gottfried Leibniz (Letters to Samuel Clarke [1716], 3.4)
27. Natural Reality / D. Time / 1. Nature of Time / i. Denying time
No time exists except instants, and instants are not even a part of time, so time does not exist [Leibniz]
     Full Idea: How could a thing exist, no part of which ever exists? In the case of time, nothing exists but instants, and an instant is not even a part of time.
     From: Gottfried Leibniz (Letters to Samuel Clarke [1716], 5.49)
27. Natural Reality / D. Time / 2. Passage of Time / a. Experience of time
If everything in the universe happened a year earlier, there would be no discernible difference [Leibniz]
     Full Idea: To ask why God did not make everything a year sooner would be reasonable if time were something apart from temporal things, but time is just the succession of things, which remains the same if the universe is created a year sooner.
     From: Gottfried Leibniz (Letters to Samuel Clarke [1716], 3.6)
28. God / A. Divine Nature / 5. God and Time
If time were absolute that would make God's existence dependent on it [Leibniz, by Bardon]
     Full Idea: Leibniz argues that if time is a thing in itself, and God is 'in' time, then God would be dependent for His existence on the existence of time.
     From: report of Gottfried Leibniz (Letters to Samuel Clarke [1716]) by Adrian Bardon - Brief History of the Philosophy of Time 3 'Newton'
     A reaction: Hence Leibniz says time is merely relations between events. Not sure what he thinks an event is. What is God made of? Is there some divine matter upon which God's existence must depend?
28. God / B. Proving God / 3. Proofs of Evidence / a. Cosmological Proof
The existence of God, and all metaphysics, follows from the Principle of Sufficient Reason [Leibniz]
     Full Idea: By this principle alone, that there must be a sufficient reason why things are thus rather than otherwise, I prove the existence of the Divinity, and all the rest of metaphysics or natural theology.
     From: Gottfried Leibniz (Letters to Samuel Clarke [1716], §2)