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All the ideas for 'How the Laws of Physics Lie', 'Logicism and Ontological Commits. of Arithmetic' and 'Letters to Antoine Arnauld'

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69 ideas

1. Philosophy / A. Wisdom / 1. Nature of Wisdom
Wisdom is the science of happiness [Leibniz]
     Full Idea: Wisdom is the science of happiness.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1690.03.23)
     A reaction: That probably comes down to common sense, or Aristotle's 'phronesis'. I take wisdom to involve understanding, as well as the quest for happiness.
1. Philosophy / A. Wisdom / 2. Wise People
Wise people have fewer acts of will, because such acts are linked together [Leibniz]
     Full Idea: The wiser one is, the fewer separate acts of will one has and the more one's views and acts of will are comprehensive and linked together.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.04.12)
     A reaction: [letter to Landgrave, about Arnauld] It is unusual to find a philosopher who actually tries to analyse the nature of wisdom, instead of just paying lipservice to it. I take Leibniz to be entirely right here. He equates wisdom with rational behaviour.
1. Philosophy / E. Nature of Metaphysics / 5. Metaphysics beyond Science
Metaphysics is geometrical, resting on non-contradiction and sufficient reason [Leibniz]
     Full Idea: I claim to give metaphysics geometric demonstrations, assuming only the principle of contradiction (or else all reasoning becomes futile), and that nothing exists without a reason, or that every truth has an a priori proof, from the concept of terms.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.07.4/14 XI)
     A reaction: For the last bit, see Idea 12910. This idea is the kind of huge optimism about metaphysic which got it a bad name after Kant, and in modern times. I'm optimistic about metaphysics, but certainly not about 'geometrical demonstrations' of it.
2. Reason / D. Definition / 4. Real Definition
Definitions can only be real if the item is possible [Leibniz]
     Full Idea: Definitions to my mind are real, when one knows that the thing defined is possible; otherwise they are only nominal, and one must not rely on them.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.07.4/14 XI)
     A reaction: It is interesting that things do not have to actual to have real definitions. For Leibniz, what is possible will exist in the mind of God. For me what is possible will exist in the potentialities of the powers of what is actual.
3. Truth / A. Truth Problems / 1. Truth
The predicate is in the subject of a true proposition [Leibniz]
     Full Idea: In a true proposition the concept of the predicate is always present in the subject.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.07.4/14 X)
     A reaction: This sounds very like the Kantian notion of an analytic truth, but Leibniz is applying it to all truths. So Socrates must contain the predicate of running as part of his nature (or essence?), if 'Socrates runs' is to be true.
A truth is just a proposition in which the predicate is contained within the subject [Leibniz]
     Full Idea: In every true affirmative proposition, necessary or contingent, universal or particular, the concept of the predicate is in a sense included in that of the subject; the predicate is present in the subject; or else I do not know what truth is.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.07.4/14)
     A reaction: Why did he qualify this with "in a sense"? This is referred to as the 'concept containment theory of truth'. This is an odd view of the subject. If the truth is 'Peter fell down stairs', we don't usually think the concept of Peter contains such things.
3. Truth / F. Semantic Truth / 2. Semantic Truth
Truth in a model is more tractable than the general notion of truth [Hodes]
     Full Idea: Truth in a model is interesting because it provides a transparent and mathematically tractable model - in the 'ordinary' rather than formal sense of the term 'model' - of the less tractable notion of truth.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984], p.131)
     A reaction: This is an important warning to those who wish to build their entire account of truth on Tarski's rigorously formal account of the term. Personally I think we should start by deciding whether 'true' can refer to the mental state of a dog. I say it can.
Truth is quite different in interpreted set theory and in the skeleton of its language [Hodes]
     Full Idea: There is an enormous difference between the truth of sentences in the interpreted language of set theory and truth in some model for the disinterpreted skeleton of that language.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984], p.132)
     A reaction: This is a warning to me, because I thought truth and semantics only entered theories at the stage of 'interpretation'. I must go back and get the hang of 'skeletal' truth, which sounds rather charming. [He refers to set theory, not to logic.]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Higher-order logic may be unintelligible, but it isn't set theory [Hodes]
     Full Idea: Brand higher-order logic as unintelligible if you will, but don't conflate it with set theory.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984], p.131)
     A reaction: [he gives Boolos 1975 as a further reference] This is simply a corrective, because the conflation of second-order logic with set theory is an idea floating around in the literature.
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
Identity is a level one relation with a second-order definition [Hodes]
     Full Idea: Identity should he considered a logical notion only because it is the tip of a second-order iceberg - a level 1 relation with a pure second-order definition.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984])
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
When an 'interpretation' creates a model based on truth, this doesn't include Fregean 'sense' [Hodes]
     Full Idea: A model is created when a language is 'interpreted', by assigning non-logical terms to objects in a set, according to a 'true-in' relation, but we must bear in mind that this 'interpretation' does not associate anything like Fregean senses with terms.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984], p.131)
     A reaction: This seems like a key point (also made by Hofweber) that formal accounts of numbers, as required by logic, will not give an adequate account of the semantics of number-terms in natural languages.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / a. Numbers
Mathematics is higher-order modal logic [Hodes]
     Full Idea: I take the view that (agreeing with Aristotle) mathematics only requires the notion of a potential infinity, ...and that mathematics is higher-order modal logic.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984])
     A reaction: Modern 'modal' accounts of mathematics I take to be heirs of 'if-thenism', which seems to have been Russell's development of Frege's original logicism. I'm beginning to think it is right. But what is the subject-matter of arithmetic?
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / a. Units
There is no multiplicity without true units [Leibniz]
     Full Idea: There is no multiplicity without true units.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1687.04.30)
     A reaction: Hence real numbers do not embody 'multiplicity'. So either they don't 'embody' anything, or they embody 'magnitudes'. Does this give two entirely different notions, of measure of multiplicity and measures of magnitude?
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / f. Arithmetic
Arithmetic must allow for the possibility of only a finite total of objects [Hodes]
     Full Idea: Arithmetic should be able to face boldly the dreadful chance that in the actual world there are only finitely many objects.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984], p.148)
     A reaction: This seems to be a basic requirement for any account of arithmetic, but it was famously a difficulty for early logicism, evaded by making the existence of an infinity of objects into an axiom of the system.
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / a. For mathematical platonism
It is claimed that numbers are objects which essentially represent cardinality quantifiers [Hodes]
     Full Idea: The mathematical object-theorist says a number is an object that represents a cardinality quantifier, with the representation relation as the entire essence of the nature of such objects as cardinal numbers like 4.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984])
     A reaction: [compressed] This a classic case of a theory beginning to look dubious once you spell it our precisely. The obvious thought is to make do with the numerical quantifiers, and dispense with the objects. Do other quantifiers need objects to support them?
Numerical terms can't really stand for quantifiers, because that would make them first-level [Hodes]
     Full Idea: The dogmatic Frege is more right than wrong in denying that numerical terms can stand for numerical quantifiers, for there cannot be a language in which object-quantifiers and objects are simultaneously viewed as level zero.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984], p.142)
     A reaction: Subtle. We see why Frege goes on to say that numbers are level zero (i.e. they are objects). We are free, it seems, to rewrite sentences containing number terms to suit whatever logical form appeals. Numbers are just quantifiers?
7. Existence / A. Nature of Existence / 3. Being / g. Particular being
What is not truly one being is not truly a being either [Leibniz]
     Full Idea: What is not truly one being is not truly a being either.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1687.04.30), quoted by Alain Badiou - Briefings on Existence 1
     A reaction: Badiou quotes this as identifying Being with the One. I say Leibniz had no concept of 'gunk', and thought everything must have a 'this' identity in order to exist, which is just the sort of thing a logician would come up with.
7. Existence / C. Structure of Existence / 5. Supervenience / a. Nature of supervenience
A thing 'expresses' another if they have a constant and fixed relationship [Leibniz]
     Full Idea: One thing 'expresses' another (in my terminology) when there exists a constant and fixed relationship between what can be said of one and of the other. This is the way that a perspectival projection expresses its ground-plan.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1687.10.09)
     A reaction: Arnauld was puzzled by what Leibniz might mean by 'express', and it occurs to me that Leibniz was fishing for the modern concept of 'supervenience'. It also sounds a bit like the idea of 'covariance' between mind and world. Maybe he means 'function'.
7. Existence / D. Theories of Reality / 7. Fictionalism
Talk of mirror images is 'encoded fictions' about real facts [Hodes]
     Full Idea: Talk about mirror images is a sort of fictional discourse. Statements 'about' such fictions are not made true or false by our whims; rather they 'encode' facts about the things reflected in mirrors.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984], p.146)
     A reaction: Hodes's proposal for how we should view abstract objects (c.f. Frege and Dummett on 'the equator'). The facts involved are concrete, but Hodes is offering 'encoding fictionalism' as a linguistic account of such abstractions. He applies it to numbers.
7. Existence / E. Categories / 4. Category Realism
Causality indicates which properties are real [Cartwright,N]
     Full Idea: Causality is a clue to what properties are real.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], 9.3)
     A reaction: An interesting variant on the Shoemaker proposal that properties actually are causal. I'm not sure that there is anything more to causality that the expression in action of properties, which I take to be powers. Structures are not properties.
8. Modes of Existence / C. Powers and Dispositions / 2. Powers as Basic
A substance contains the laws of its operations, and its actions come from its own depth [Leibniz]
     Full Idea: Each indivisible substance contains in its nature the law by which the series of its operations continues, and all that has happened and will happen to it. All its actions come from its own depths, except for dependence on God.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1688.01.4/14)
     A reaction: I take the combination of 'laws' and 'forces', which Leibniz attributes to Aristotelian essences, to be his distinctive contribution towards giving us an Aristotelian metaphysic which is suitable for modern science.
9. Objects / B. Unity of Objects / 1. Unifying an Object / a. Intrinsic unification
Philosophy needs the precision of the unity given by substances [Leibniz]
     Full Idea: Philosophy cannot be better reduced to something precise, than by recognising only substances or complete beings endowed with a true unity, with different states that succeed one another; all else is phenomena, abstractions or relations.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1687.04.30), quoted by Daniel Garber - Leibniz:Body,Substance,Monad 7
     A reaction: This idea bothers me. Has the whole of modern philosophy been distorted by this yearning for 'precision'? It has put mathematicians and logicians in the driving seat. Do we only attribute unity because it suits our thinking?
9. Objects / B. Unity of Objects / 1. Unifying an Object / b. Unifying aggregates
Accidental unity has degrees, from a mob to a society to a machine or organism [Leibniz]
     Full Idea: There are degrees of accidental unity, and an ordered society has more unity than a chaotic mob, and an organic body or a machine has more unity than a society.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1687.04.30)
     A reaction: This immediately invites questions about the extremes. Why does the very highest degree of 'accidental unity' not achieve 'true unity'? And why cannot a very ununified aggregate have a bit of unity (as in unrestricted mereological composition)?
9. Objects / B. Unity of Objects / 1. Unifying an Object / c. Unity as conceptual
We find unity in reason, and unity in perception, but these are not true unity [Leibniz]
     Full Idea: A pair of diamonds is merely an entity of reason, and even if one of them is brought close to another, it is an entity of imagination or perception, that is to say a phenomenon; contiguity, common movement and the same end don't make substantial unity.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1687.04.30), quoted by Daniel Garber - Leibniz:Body,Substance,Monad 7
     A reaction: This invites the question of what you have to do to two objects to give them substantial unity. The distinction between unity 'of reason' and unity 'of perception' is good.
9. Objects / B. Unity of Objects / 2. Substance / a. Substance
A body is a unified aggregate, unless it has an indivisible substance [Leibniz]
     Full Idea: One will never find a body of which it may be said that it is truly one substance, ...because entities made up by aggregation have only as much reality as exists in the constituent parts. Hence the substance of a body must be indivisible.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.11)
     A reaction: Leibniz rejected atomism, and he evidently believed that pure materialists must deny the real existence of physical objects. Common sense suggests that causal bonds bestow a high degree of unity on bodies (if degrees are allowed).
Unity needs an indestructible substance, to contain everything which will happen to it [Leibniz]
     Full Idea: Substantial unity requires a complete, indivisible and naturally indestructible entity, since its concept embraces everything that is to happen to it, which cannot be found in shape or motion.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.11.28/12.8)
     A reaction: Hence if a tile is due to be broken in half (Arnauld's example), it cannot have had unity in the first place. To what do we refer when we say 'the tile was broken'?
Every bodily substance must have a soul, or something analogous to a soul [Leibniz]
     Full Idea: Every bodily substance must have a soul, or at least an entelechy which is analogous to the soul.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1687.10.09)
     A reaction: He routinely commits to a 'soul', and then pulls back and says it may only be an 'analogy'. He had deep doubts about his whole scheme, which emerged in the late correspondence with Des Bosses. This not monads, says Garber.
9. Objects / B. Unity of Objects / 2. Substance / b. Need for substance
Aggregates don’t reduce to points, or atoms, or illusion, so must reduce to substance [Leibniz]
     Full Idea: In aggregates one must necessarily arrive either at mathematical points from which some make up extension, or at atoms (which I dismiss), or else no reality can be found in bodies, or finally one must recognises substances that possess a true unity.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1687.04.30), quoted by Daniel Garber - Leibniz:Body,Substance,Monad 2
     A reaction: Garber calls this Leibniz's Aggregate Argument. Leibniz is, of course, talking of physical aggregates which have unity. He consistently points out that a pile of logs has no unity at all. But is substance just that-which-provides-unity?
9. Objects / D. Essence of Objects / 1. Essences of Objects
Basic predicates give the complete concept, which then predicts all of the actions [Leibniz]
     Full Idea: Apart from those that depend on others, one must only consider together all the basic predicates in order to form the complete concept of Adam adequate to deduce from it everything that is ever to happen to him, as much as is necessary to account for it.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.06)
     A reaction: This (implausibly) goes beyond mere prediction of properties. Eve's essence seems to be relevant to Adam's life. Note that the complete concept is not every predicate, but only those 'necessary' to predict the events. Cf Idea 13082.
Essences exist in the divine understanding [Leibniz]
     Full Idea: Essences exist in the divine understanding before one considers will.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.07.4/14 X)
     A reaction: This is a sort of religious neo-platonism. The great dream seems to be that of mind-reading God, and the result is either Pythagoras (it's numbers!), or Plato (it's pure ideas!), or this (it's essences!). See D.H.Lawrence's poem on geranium and mignottes.
9. Objects / D. Essence of Objects / 6. Essence as Unifier
Bodies need a soul (or something like it) to avoid being mere phenomena [Leibniz]
     Full Idea: Every substance is indivisible and consequently every corporeal substance must have a soul or at least an entelechy which is analogous to the soul, since otherwise bodies would be no more than phenomena.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], G II 121), quoted by Daniel Garber - Leibniz:Body,Substance,Monad 2
     A reaction: There is a large gap between having 'a soul' and having something 'analogous to a soul'. I take the analogy to be merely as originators of action. Leibniz wants to add appetite and sensation to the Aristotelian forms (but knows this is dubious!).
9. Objects / D. Essence of Objects / 10. Essence as Species
Truths about species are eternal or necessary, but individual truths concern what exists [Leibniz]
     Full Idea: The concept of a species contains only eternal or necessary truths, whereas the concept of an individual contains, regarded as possible, what in fact exists or what is related to the existence of things and to time.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.06)
     A reaction: This seems to be what is behind the preference some have for kind-essences rather than individual essences. But the individual must be explained, as well as the kind. Not all tigers are identical. The two are, of course, compatible.
10. Modality / E. Possible worlds / 3. Transworld Objects / a. Transworld identity
If varieties of myself can be conceived of as distinct from me, then they are not me [Leibniz]
     Full Idea: I can as little conceive of different varieties of myself as of a circle whose diameters are not all of equal length. These variations would all be distinct one from another, and thus one of these varieties of myself would necessarily not be me.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.05.13)
     A reaction: This seems to be, at the very least, a rejection of any idea that I could have a 'counterpart'. It is unclear, though, where he would place a version of himself who learned a new language, or who might have had, but didn't have, a haircut.
If someone's life went differently, then that would be another individual [Leibniz]
     Full Idea: If the life of some person, or something went differently than it does, nothing would stop us from saying that it would be another person, or another possible universe which God had chosen. So truly it would be another individual.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.07.14)
     A reaction: Plantinga quotes this as an example of 'worldbound individuals'. This sort of remark leads to people saying that Leibniz believes all properties are essential, since they assume that his notion of essence is bound up with identity. But is it?
11. Knowledge Aims / B. Certain Knowledge / 4. The Cogito
I cannot think my non-existence, nor exist without being myself [Leibniz]
     Full Idea: I am assured that as long as I think, I am myself. For I cannot think that I do not exist, nor exist so that I be not myself.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.05.13)
     A reaction: Elsewhere he qualifies the Cogito, but here he seems to straighforwardly endorse it.
11. Knowledge Aims / B. Certain Knowledge / 5. Cogito Critique
I can't just know myself to be a substance; I must distinguish myself from others, which is hard [Leibniz]
     Full Idea: It is not enough for understanding the nature of myself, that I feel myself to be a thinking substance, one would have to form a distinct idea of what distinguishes me from all other possible minds; but of that I have only a confused experience.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.07.4/14)
     A reaction: Not a criticism I have encountered before. Does he mean that I might be two minds, or might be a multitude of minds? It seems to be Hume's problem, that you are aware of experiences, but not of the substance that unites them.
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / a. Foundationalism
Nothing should be taken as certain without foundations [Leibniz]
     Full Idea: Nothing should be taken as certain without foundations.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1687.04.30)
     A reaction: This might leave open the option, if you were a modern 'Fallibilist', that something might lack foundations, and so not be certain, and yet still qualify as 'knowledge'. That is my view. Knowledge resides somewhere between opinion and certainty.
14. Science / D. Explanation / 2. Types of Explanation / a. Types of explanation
Nature is explained by mathematics and mechanism, but the laws rest on metaphysics [Leibniz]
     Full Idea: One must always explain nature along mathematical and mechanical lines, provided one knows that the very principles or laws of mechanics or of force do not depend upon mathematical extension alone but upon certain metaphysical reasons.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.07.4/14 X)
     A reaction: I like this, and may even use it as the epigraph of my masterwork. Recently Stephen Hawking (physicist) has been denigrating philosophy, but I am with Leibniz on this one.
Two main types of explanation are by causes, or by citing a theoretical framework [Cartwright,N]
     Full Idea: In explaining a phenomenon one can cite the causes of that phenomenon; or one can set the phenomenon in a general theoretical framework.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], 4.1)
     A reaction: The thing is, you need to root an explanation in something taken as basic, and theoretical frameworks need further explanation, whereas causes seem to be basic.
14. Science / D. Explanation / 2. Types of Explanation / c. Explanations by coherence
An explanation is a model that fits a theory and predicts the phenomenological laws [Cartwright,N]
     Full Idea: To explain a phenomenon is to find a model that fits it into the basic framework of the theory and that thus allows us to derive analogues for the messy and complicated phenomenological laws that are true of it.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], 8.3)
     A reaction: This summarises the core of her view in this book. She is after models rather than laws, and the models are based on causes.
14. Science / D. Explanation / 2. Types of Explanation / e. Lawlike explanations
Laws get the facts wrong, and explanation rests on improvements and qualifications of laws [Cartwright,N]
     Full Idea: We explain by ceteris paribus laws, by composition of causes, and by approximations that improve on what the fundamental laws dictate. In all of these cases the fundamental laws patently do not get the facts right.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], Intro)
     A reaction: It is rather headline-grabbing to say in this case that laws do not get the facts right. If they were actually 'wrong' and 'lied', there wouldn't be much point in building explanations on them.
Laws apply to separate domains, but real explanations apply to intersecting domains [Cartwright,N]
     Full Idea: When different kinds of causes compose, we want to explain what happens in the intersection of different domains. But the laws we use are designed only to tell truly what happens in each domain separately.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], Intro)
     A reaction: Since presumably the laws are discovered through experiments which try to separate out a single domain, in those circumstances they actually are true, so they don't 'lie'.
Covering-law explanation lets us explain storms by falling barometers [Cartwright,N]
     Full Idea: Much criticism of the original covering-law model objects that it lets in too much. It seems we can explain Henry's failure to get pregnant by his taking birth control pills, and we can explain the storm by the falling barometer.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], 2.0)
     A reaction: I take these examples to show that true explanations must be largely causal in character. The physicality of causation is what matters, not 'laws'. I'd say the same of attempts to account for causation through counterfactuals.
I disagree with the covering-law view that there is a law to cover every single case [Cartwright,N]
     Full Idea: Covering-law theorists tend to think that nature is well-regulated; in the extreme, that there is a law to cover every case. I do not.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], 2.2)
     A reaction: The problem of coincidence is somewhere at the back of this thought. Innumerable events have their own explanations, but it is hard to explain their coincidence (see Aristotle's case of bumping into a friend in the market).
You can't explain one quail's behaviour by just saying that all quails do it [Cartwright,N]
     Full Idea: 'Why does that quail in the garden bob its head up and down in that funny way whenever it walks?' …'Because they all do'.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], 3.5)
     A reaction: She cites this as an old complaint against the covering-law model of explanation. It captures beautifully the basic error of the approach. We want to know 'why', rather than just have a description of the pattern. 'They all do' is useful information.
The covering law view assumes that each phenomenon has a 'right' explanation [Cartwright,N]
     Full Idea: The covering-law account supposes that there is, in principle, one 'right' explanation for each phenomenon.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], Intro)
     A reaction: Presumably the law is held to be 'right', but there must be a bit of flexibility in describing the initial conditions, and the explanandum itself.
14. Science / D. Explanation / 2. Types of Explanation / k. Explanations by essence
To fully conceive the subject is to explain the resulting predicates and events [Leibniz]
     Full Idea: Even in the most contingent truths, there is always something to be conceived in the subject which serves to explain why this predicate or event pertains to it, or why this has happened rather than not.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.06)
     A reaction: The last bit, about containing what has happened, seems absurd, but the rest of it makes sense. It is just the Aristotelian essentialist view, that a full understanding of the inner subject will both explain and predict the surface properties.
14. Science / D. Explanation / 3. Best Explanation / c. Against best explanation
In science, best explanations have regularly turned out to be false [Cartwright,N]
     Full Idea: There are a huge number of cases in the history of science where we now know our best explanations were false.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], 5.3)
     A reaction: [She cites Laudan 1981 for this] The Ptolemaic system and aether are the standard example cited for this. I believe strongly in the importance of best explanation. Only a fool would just accept the best explanation available. Coherence is needed.
15. Nature of Minds / A. Nature of Mind / 1. Mind / b. Purpose of mind
Mind is a thinking substance which can know God and eternal truths [Leibniz]
     Full Idea: Minds are substances which think, and are capable of knowing God and of discovering eternal truths.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1687.10.09)
     A reaction: 'God' is there because the ability to grasp the ontological argument is seen as basic. Note a firm commitment to substance-dualism, and a rationalist commitment to the spotting of necessary truths as basic. He is not totally wrong.
15. Nature of Minds / A. Nature of Mind / 7. Animal Minds
It seems probable that animals have souls, but not consciousness [Leibniz]
     Full Idea: It appears probable that the brutes have souls, though they are without consciousness.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.12.08)
     A reaction: This will be a response to Descartes, who allowed animals sensations, but not minds or souls. Personally I cannot make head or tail of Leibniz's claim. What makes it "apparent" to him?
16. Persons / F. Free Will / 7. Compatibilism
Everything which happens is not necessary, but is certain after God chooses this universe [Leibniz]
     Full Idea: It is not the case that everything which happens is necessary; rather, everything which happens is certain after God made choice of this possible universe, whose notion contains this series of things.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.05)
     A reaction: I think this distinction is best captured as 'metaphysical necessity' (Leibniz's 'necessity'), and 'natural necessity' (his 'certainty'). 'Certainty' seems a bad word, as it is either certain de dicto or de re. Is God certain, or is the thing certain?
18. Thought / D. Concepts / 1. Concepts / a. Nature of concepts
Concepts are what unite a proposition [Leibniz]
     Full Idea: There must always be some basis for the connexion between the terms of a proposition, and it is to be found in their concepts.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.07.4/14 X)
     A reaction: We face the problem that bothered Russell, of the unity of the proposition. We are also led to the question of HOW our concepts connect the parts of a proposition. Do concepts have valencies? Are they incomplete, as Frege suggests?
21. Aesthetics / A. Aesthetic Experience / 4. Beauty
Beauty increases with familiarity [Leibniz]
     Full Idea: The more one is familiar with things, the more beautiful one finds them.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1688.01.4/14)
     A reaction: This is always the reply given to those who say that science kills our sense of beauty. The first step in aesthetic life is certainly to really really pay attention to things.
22. Metaethics / C. The Good / 2. Happiness / a. Nature of happiness
Happiness is advancement towards perfection [Leibniz]
     Full Idea: Happiness, or lasting contentment, consists of continual advancement towards a greater perfection.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1690.03.23)
     A reaction: To the modern mind this smacks of the sort of hubris to which only the religious mind can aspire, but it's still rather nice. The idea of grubby little mammals approaching perfection sounds wrong, but which other animal has even thought of perfection?
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / g. Atomism
I think the corpuscular theory, rather than forms or qualities, best explains particular phenomena [Leibniz]
     Full Idea: I still subscribe fully to the corpuscular theory in the explanation of particular phenomena; in this sphere it is of no value to speak of forms or qualities.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 14.07.1686)
     A reaction: I am puzzled by Garber's summary in Idea 12728, and a bit unclear on Leibniz's views on atoms. More needed.
26. Natural Theory / C. Causation / 8. Particular Causation / e. Probabilistic causation
A cause won't increase the effect frequency if other causes keep interfering [Cartwright,N]
     Full Idea: A cause ought to increase the frequency of the effect, but this fact may not show up in the probabilities if other causes are at work.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], 1.1)
     A reaction: [She cites Patrick Suppes for this one] Presumably in experimental situations you can weed out the interference, but that threatens to eliminate mere 'probability' entirely.
26. Natural Theory / D. Laws of Nature / 1. Laws of Nature
Each possible world contains its own laws, reflected in the possible individuals of that world [Leibniz]
     Full Idea: As there exist an infinite number of possible worlds, there exists also an infinite number of laws, some peculiar to one world, some to another, and each individual of any one world contains in the concept of him the laws of his world.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.06)
     A reaction: Since Leibniz's metaphysics is thoroughly God-driven, he will obviously allow God to create any laws He wishes, and hence scientific essentialism seems to be rejected, even though Leibniz is keen on essences. Unless the stuff is different...
26. Natural Theory / D. Laws of Nature / 2. Types of Laws
There are fundamental explanatory laws (false!), and phenomenological laws (regularities) [Cartwright,N, by Bird]
     Full Idea: Nancy Cartwright distinguishes between 'fundamental explanatory laws', which we should not believe, and 'phenomenological laws', which are regularities established on the basis of observation.
     From: report of Nancy Cartwright (How the Laws of Physics Lie [1983]) by Alexander Bird - Philosophy of Science Ch.4
     A reaction: The distinction is helpful, so that we can be clearer about what everyone is claiming. We can probably all agree on the phenomenological laws, which are epistemological. Personally I claim truth for the best fundamental explanatory laws.
Laws of appearances are 'phenomenological'; laws of reality are 'theoretical' [Cartwright,N]
     Full Idea: Philosophers distinguish phenomenological from theoretical laws. Phenomenological laws are about appearances; theoretical ones are about the reality behind the appearances.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], Intro)
     A reaction: I'm suspecting that Humeans only really believe in the phenomenological kind. I'm only interested in the theoretical kind, and I take inference to the best explanation to be the bridge between the two. Cartwright rejects the theoretical laws.
26. Natural Theory / D. Laws of Nature / 4. Regularities / b. Best system theory
Good organisation may not be true, and the truth may not organise very much [Cartwright,N]
     Full Idea: There is no reason to think that the principles that best organise will be true, nor that the principles that are true will organise much.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], 2.5)
     A reaction: This is aimed at the Mill-Ramsey-Lewis account of laws, as axiomatisations of the observed patterns in nature.
26. Natural Theory / D. Laws of Nature / 11. Against Laws of Nature
To get from facts to equations, we need a prepared descriptions suited to mathematics [Cartwright,N]
     Full Idea: To get from a detailed factual knowledge of a situation to an equation, we must prepare the description of the situation to meet the mathematical needs of the theory.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], Intro)
     A reaction: She is clearly on to something here, as Galileo is blatantly wrong in his claim that the book of nature is written in mathematics. Mathematics is the best we can manage in getting a grip on the chaos.
Simple laws have quite different outcomes when they act in combinations [Cartwright,N]
     Full Idea: For explanation simple laws must have the same form when they act together as when they act singly. ..But then what the law states cannot literally be true, for the consequences that occur if it acts alone are not what occurs when they act in combination.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], 3.6)
     A reaction: This is Cartwright's basic thesis. Her point is that the laws 'lie', because they claim to predict a particular outcome which never ever actually occurs. She says we could know all the laws, and still not be able to explain anything.
There are few laws for when one theory meets another [Cartwright,N]
     Full Idea: Where theories intersect, laws are usually hard to come by.
     From: Nancy Cartwright (How the Laws of Physics Lie [1983], 2.3)
     A reaction: There are attempts at so-called 'bridge laws', to get from complex theories to simple ones, but her point is well made about theories on the same 'level'.
27. Natural Reality / A. Classical Physics / 1. Mechanics / c. Forces
Motion alone is relative, but force is real, and establishes its subject [Leibniz]
     Full Idea: Motion in itself separated from force is merely relative, and one cannot establish its subject. But force is something real and absolute.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1688.01.4/14)
     A reaction: The striking phrase here is that force enables us to 'establish its subject'. That is, force is at the heart of reality, and hence, through causal relations, individuates objects. That's how I read it.
28. God / B. Proving God / 3. Proofs of Evidence / e. Miracles
Everything, even miracles, belongs to order [Leibniz]
     Full Idea: Everything, even miracles, belongs to order.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.07.4/14 X)
     A reaction: This is very reminiscent of Plato, for whom there was no more deeply held belief than that the cosmos is essentially orderly. Coincidences are a nice problem, if they are events with no cause.
Miracles are extraordinary operations by God, but are nevertheless part of his design [Leibniz]
     Full Idea: Miracles, or the extraordinary operations of God, none the less belong within the general order; they are in conformity with the principal designs of God, and consequently are included in the notion of this universe, which is the result of those designs.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.05)
     A reaction: Some philosophers just make up things to suit themselves. What possible grounds can he have for claiming this? At best this is tautological, saying that, by definition, if anything at all happens, it must be part of God's design. Move on to Hume…
29. Religion / D. Religious Issues / 2. Immortality / a. Immortality
Immortality without memory is useless [Leibniz]
     Full Idea: Immortality without memory would be useless.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.07.4/14 X)
     A reaction: I would say that having a mind of any sort needs memory. The question for immortality is whether it extends back to human life. See 'Wuthering Heights' (c. p90) for someone who remembers Earth as so superior to paradise that they long to return there.
29. Religion / D. Religious Issues / 2. Immortality / b. Soul
The soul is indestructible and always self-aware [Leibniz]
     Full Idea: Not only is the soul indestructible, but it always knows itself and remains self-conscious.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.11)
     A reaction: Personally I am not even self-aware during much of my sleeping hours, and I would say that I cease to be self-aware if I am totally absorbed in something on which I concentrate.
29. Religion / D. Religious Issues / 2. Immortality / c. Animal Souls
Animals have souls, but lack consciousness [Leibniz]
     Full Idea: It appears probable that animals have souls although they lack consciousness.
     From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.11)
     A reaction: Personally I would say that they lack souls but have consciousness, but then I am in no better position to know the answer than Leibniz was. Arnauld asks what would happen to the souls of 100,000 silkworms if they caught fire!