Combining Philosophers

All the ideas for H.Putnam/P.Oppenheim, Gideon Rosen and Alvin Plantinga

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74 ideas

1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
Philosophers are often too fussy about words, dismissing perfectly useful ordinary terms [Rosen]
     Full Idea: Philosophers can sometimes be too fussy about the words they use, dismissing as 'unintelligible' or 'obscure' certain forms of language that are perfectly meaningful by ordinary standards, and which may be of some real use.
     From: Gideon Rosen (Metaphysical Dependence [2010], 01)
     A reaction: Analytic philosophers are inclined to drop terms they can't formalise, but there is more to every concept than its formalisation (Frege's 'direction' for example). I want to rescue 'abstraction' and 'essence'. Rosen says distinguish, don't formalise.
2. Reason / D. Definition / 1. Definitions
Figuring in the definition of a thing doesn't make it a part of that thing [Rosen]
     Full Idea: From the simple fact that '1' figures in the definition of '2', it does not follow that 1 is part of 2.
     From: Gideon Rosen (Metaphysical Dependence [2010], 10)
     A reaction: He observes that quite independent things can be mentioned on the two sides of a definition, with no parthood relation. You begin to wonder what a definition really is. A causal chain?
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / c. Axiom of Pairing II
Pairing (with Extensionality) guarantees an infinity of sets, just from a single element [Rosen]
     Full Idea: In conjunction with Extensionality, Pairing entails that given a single non-set, infinitely many sets exist.
     From: Gideon Rosen (The Limits of Contingency [2006], 04)
5. Theory of Logic / F. Referring in Logic / 1. Naming / a. Names
Maybe proper names involve essentialism [Plantinga]
     Full Idea: Perhaps the notion of a proper name itself involves essentialism.
     From: Alvin Plantinga (De Re and De Dicto [1969], p.43)
     A reaction: This is just before Kripke's announcement of 'rigid designation', which seems to have relaunched modern essentialism. The thought is that you can't name something, if you don't have a stable notion of what is (and isn't) being named.
5. Theory of Logic / K. Features of Logics / 10. Monotonicity
Explanations fail to be monotonic [Rosen]
     Full Idea: The failure of monotonicity is a general feature of explanatory relations.
     From: Gideon Rosen (Metaphysical Dependence [2010], 05)
     A reaction: In other words, explanations can always shift in the light of new evidence. In principle this is right, but some explanations just seem permanent, like plate-tectonics as explanation for earthquakes.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
Could I name all of the real numbers in one fell swoop? Call them all 'Charley'? [Plantinga]
     Full Idea: Can't I name all the real numbers in the interval (0,1) at once? Couldn't I name them all 'Charley', for example?
     From: Alvin Plantinga (De Re and De Dicto [1969], p.40)
     A reaction: Plantinga is nervous about such a sweeping move, but can't think of an objection. This addresses a big problem, I think - that you are supposed to accept the real numbers when we cannot possibly name them all.
7. Existence / A. Nature of Existence / 3. Being / a. Nature of Being
Necessary beings (numbers, properties, sets, propositions, states of affairs, God) exist in all possible worlds [Plantinga]
     Full Idea: A 'necessary being' is one that exists in every possible world; and only some objects - numbers, properties, pure sets, propositions, states of affairs, God - have this distinction.
     From: Alvin Plantinga (Actualism and Possible Worlds [1976], 2)
     A reaction: This a very odd list, though it is fairly orthodox among philosophers trained in modern modal logic. At the very least it looks rather parochial to me.
7. Existence / C. Structure of Existence / 1. Grounding / a. Nature of grounding
Things could be true 'in virtue of' others as relations between truths, or between truths and items [Rosen]
     Full Idea: Our relation of 'in virtue of' is among facts or truths, whereas Fine's relation (if it is a relation at all) is a relation between a given truth and items whose natures ground that truth.
     From: Gideon Rosen (Metaphysical Dependence [2010], 07 n10)
     A reaction: This disagreement between two key players in the current debate on grounding looks rather significant. I think I favour Fine's view, as it seems more naturalistic, and less likely to succumb to conventionalism.
7. Existence / D. Theories of Reality / 8. Facts / a. Facts
Facts are structures of worldly items, rather like sentences, individuated by their ingredients [Rosen]
     Full Idea: Facts are structured entities built up from worldly items rather as sentences are built up from words. They might be identified with Russellian propositions. They are individuated by their constituents and composition, and are fine-grained.
     From: Gideon Rosen (Metaphysical Dependence [2010], 04)
     A reaction: I'm a little cautious about the emphasis on being sentence-like. We have Russell's continual warnings against imposing subject-predicate structure on things. I think we should happily talk about 'facts' in metaphysics.
8. Modes of Existence / B. Properties / 4. Intrinsic Properties
An 'intrinsic' property is one that depends on a thing and its parts, and not on its relations [Rosen]
     Full Idea: One intuitive gloss on 'intrinsic' property is that a property is intrinsic iff whether or not a thing has it depends entirely on how things stand with it and its parts, and not on its relation to some distinct thing.
     From: Gideon Rosen (Metaphysical Dependence [2010], 02)
     A reaction: He offers this as a useful reward for reviving 'depends on' in metaphysical talk. The problem here would be to explain the 'thing' and its 'parts' without mentioning the target property. The thing certainly can't be a bundle of tropes.
9. Objects / A. Existence of Objects / 2. Abstract Objects / d. Problems with abstracta
How we refer to abstractions is much less clear than how we refer to other things [Rosen]
     Full Idea: It is unclear how we manage to refer determinately to abstract entities in a sense in which it is not unclear how we manage to refer determinately to other things.
     From: Gideon Rosen (Abstract Objects [2001], 'Way of Ex')
     A reaction: This is where problems of abstraction overlap with problems about reference in language. Can we have a 'baptism' account of each abstraction (even very large numbers)? Will descriptions do it? Do abstractions collapse into particulars when we refer?
9. Objects / A. Existence of Objects / 4. Impossible objects
Plantinga proposes necessary existent essences as surrogates for the nonexistent things [Plantinga, by Stalnaker]
     Full Idea: Plantinga proposes surrogates for nonexistent things - individual essences that are themselves necessary existents and that correspond one-to-one with all the 'things' that might exist.
     From: report of Alvin Plantinga (World and Essence [1970]) by Robert C. Stalnaker - Mere Possibilities 1
     A reaction: There are an awful lot of competing concepts of essence flying around these days. This one seems to require some abstract 'third realm' (or worse) in which these essences can exist, awaiting the arrival of thinkers. Not for me.
A Meinongian principle might say that there is an object for any modest class of properties [Rosen]
     Full Idea: Meinongian abstraction principles say that for any (suitably restricted) class of properties, there exists an abstract entity (arbitrary object, subsistent entity) that possesses just those properties.
     From: Gideon Rosen (The Limits of Contingency [2006], 04)
     A reaction: This is 'Meinongian' because there will be an object which is circular and square. The nub of the idea presumably resides in what is meant by 'restricted'. An object possessing every conceivable property is, I guess, a step too far.
9. Objects / A. Existence of Objects / 5. Individuation / a. Individuation
The 'identity criteria' of a name are a group of essential and established facts [Plantinga]
     Full Idea: What we might call 'identity criteria' associated with a name such as 'Aristotle' are what the users of the name regard as essential and established facts about him.
     From: Alvin Plantinga (World and Essence [1970], I)
     A reaction: The problem here is that identifying something is superficial, whereas essences run deep. Plantinga is, in fact, talking about Lockean 'nominal essence' (and seems unaware of the fact, and never mentions the Lockean real/nominal distinction).
9. Objects / A. Existence of Objects / 5. Individuation / d. Individuation by haecceity
Surely self-identity is essential to Socrates? [Plantinga]
     Full Idea: If anything is essential to Socrates, surely self-identity is.
     From: Alvin Plantinga (De Re and De Dicto [1969], p.37)
     A reaction: This is the modern move of Plantinga and Adams, to make 'is identical with Socrates' the one property which assures the identity of Socrates (his 'haecceity'). My view is that self-identity is not a property. Plantinga wonders about that on p.44.
'Being Socrates' and 'being identical with Socrates' characterise Socrates, so they are among his properties [Plantinga]
     Full Idea: Surely it is true of Socrates that he is Socrates and he is identical with Socrates. If these are true of him, then 'being Socrates' and 'being identical with Socrates' characterize him; they are among his properties or attributes.
     From: Alvin Plantinga (World and Essence [1970], II)
     A reaction: As far as I can see (if you insist on accepting self-identity as meaningful) the most you get here is that these are predicates that can attach to Socrates. If you identify predicates with properties you are in deep metaphysical trouble.
A snowball's haecceity is the property of being identical with itself [Plantinga, by Westerhoff]
     Full Idea: Plantinga assumes that being identical with that snowball names a property which is that snowball's haecceity.
     From: report of Alvin Plantinga (De Essentia [1979]) by Jan Westerhoff - Ontological Categories §52
     A reaction: Only a philosopher would suggest such a bizarre way of establishing the unique individuality of a given snowball. You could hardly keep track of the snowball with just that criterion. How do you decide whether something has Plantinga's property?
9. Objects / D. Essence of Objects / 1. Essences of Objects
Socrates is a contingent being, but his essence is not; without Socrates, his essence is unexemplified [Plantinga]
     Full Idea: Socrates is a contingent being; his essence, however, is not. Properties, like propositions and possible worlds, are necessary beings. If Socrates had not existed, his essence would have been unexemplified, but not non-existent.
     From: Alvin Plantinga (Actualism and Possible Worlds [1976], 4)
     A reaction: This is a distinctive Plantinga view, of which I can make little sense. I take it that Socrates used to have an essence. Being dead, the essence no longer exists, but when we talk about Socrates it is largely this essence to which we refer. OK?
9. Objects / D. Essence of Objects / 2. Types of Essence
Does Socrates have essential properties, plus a unique essence (or 'haecceity') which entails them? [Plantinga]
     Full Idea: Does Socrates have, in addition to his essential properties, an 'essence' or 'haecceity' - a property essential to him that entails each of his essential properties and that nothing distinct from him has in the world?
     From: Alvin Plantinga (World and Essence [1970], II)
     A reaction: Plantinga says yes, and offers 'Socrateity' (borrowed from Boethius) as his candidate. This is a very odd use of the word 'essence'. I take an essence to be a complex set of fundamental properties. I am also puzzled by his use of the word 'entails'.
9. Objects / D. Essence of Objects / 9. Essence and Properties
An object has a property essentially if it couldn't conceivably have lacked it [Plantinga]
     Full Idea: An object has a property essentially just in case it couldn't conceivably have lacked that property.
     From: Alvin Plantinga (De Re and De Dicto [1969], p.35)
     A reaction: Making it depend on what we can conceive seems a bit dubious, for someone committed to real essences. The key issue is how narrowly or broadly you interpret the word 'property'. The word 'object' needs a bit of thought, too!
Properties are 'trivially essential' if they are instantiated by every object in every possible world [Plantinga]
     Full Idea: Let us call properties that enjoy the distinction of being instantiated by every object in every possible world 'trivially essential properties'.
     From: Alvin Plantinga (World and Essence [1970], I)
     A reaction: These would appear to be trivially 'necessary' rather than 'essential'. This continual need for the qualifier 'trivial' shows that they are not talking about proper essences.
X is essentially P if it is P in every world, or in every X-world, or in the actual world (and not ¬P elsewhere) [Plantinga]
     Full Idea: Socrates has P essentially if he has P in every world, or has it in every world in which he exists, or - most plausible of all - has P in the actual world and has its complement [non-P] in no world.
     From: Alvin Plantinga (World and Essence [1970], Intro)
     A reaction: These strike me as mere necessary properties, which are not the same thing at all. Essences give rise to the other properties, but Plantinga offers nothing to do the job (and especially not 'Socrateity'!). Essences must explain, say I!
If a property is ever essential, can it only ever be an essential property? [Plantinga]
     Full Idea: Is it the case that any property had essentially by anything is had essentially by everything that has it?
     From: Alvin Plantinga (World and Essence [1970], III)
     A reaction: Plantinga says it is not true, but the only example he can give is Socrates having the property of 'being Socrates or Greek'. I take it to be universally false. There are not two types of property here. Properties sometimes play an essential role.
Essences are instantiated, and are what entails a thing's properties and lack of properties [Plantinga]
     Full Idea: E is an essence if and only if (a) 'has E essentially' is instantiated in some world or other, and (b) for any world W and property P, E entails 'has P in W' or 'does not have P in W'.
     From: Alvin Plantinga (World and Essence [1970], IV)
     A reaction: 'Entail' strikes me as a very odd word when you are talking about the structure of the physical world (or are we??). Why would a unique self-identity (his candidate for essence) do the necessary entailing?
9. Objects / F. Identity among Objects / 5. Self-Identity
Does 'being identical with Socrates' name a property? I can think of no objections to it [Plantinga]
     Full Idea: Is there any reason to suppose that 'being identical with Socrates' names a property? Well, is there any reason to suppose that it does not? I cannot think of any, nor have I heard any that are at all impressive.
     From: Alvin Plantinga (World and Essence [1970], II)
     A reaction: Is there any reason to think that a planet somewhere is entirely under the control of white mice? Extraordinary. No wonder Plantinga believes in God and the Ontological Argument, as well as the existence of 'Socrateity' etc.
10. Modality / A. Necessity / 4. De re / De dicto modality
Expressing modality about a statement is 'de dicto'; expressing it of property-possession is 'de re' [Plantinga]
     Full Idea: Some statements predicate modality of another statement (modality 'de dicto'); but others predicate of an object the necessary or essential possession of a property; these latter express modality 'de re'.
     From: Alvin Plantinga (De Re and De Dicto [1969], p.26)
     A reaction: The distinction seems to originate in Aquinas, concerning whether God knows the future (or, how he knows the future). 'De dicto' is straightforward, but possibly the result of convention. 'De re' is controversial, and implies deep metaphysics.
'De dicto' true and 'de re' false is possible, and so is 'de dicto' false and 'de re' true [Plantinga]
     Full Idea: Aquinas says if a 'de dicto' statement is true, the 'de re' version may be false. The opposite also applies: 'What I am thinking of [17] is essentially prime' is true, but 'The proposition "what I am thinking of is prime" is necessarily true' is false.
     From: Alvin Plantinga (De Re and De Dicto [1969], p.27)
     A reaction: In his examples the first is 'de re' (about the number), and the second is 'de dicto' (about that proposition).
Can we find an appropriate 'de dicto' paraphrase for any 'de re' proposition? [Plantinga]
     Full Idea: To explain the 'de re' via the 'de dicto' is to provide a rule enabling us to find, for each de re proposition, an equivalent de dicto proposition.
     From: Alvin Plantinga (De Re and De Dicto [1969], p.41)
     A reaction: Many 'de dicto' paraphrases will change the modality of a 'de re' statement, so the challenge is to find the right equivalent version. Plantinga takes up this challenge. The 'de dicto' statement says the object has the property, and must have it.
'De re' modality is as clear as 'de dicto' modality, because they are logically equivalent [Plantinga]
     Full Idea: The idea of modality 'de re' is no more (although no less) obscure that the idea of modality 'de dicto'; for I think we can see that any statement of the former type is logically equivalent to some statement of the latter.
     From: Alvin Plantinga (World and Essence [1970], Intro)
     A reaction: If two things are logically equivalent, that doesn't ensure that they are equally clear! Personally I am on the side of de re modality.
10. Modality / A. Necessity / 5. Metaphysical Necessity
Metaphysical necessity is absolute and universal; metaphysical possibility is very tolerant [Rosen]
     Full Idea: If P is metaphysically necessary, then it is absolutely necessary, and necessary in every real (non-epistemic) sense; and if P is possible in any sense, then it's possible in the metaphysical sense.
     From: Gideon Rosen (The Limits of Contingency [2006], 02)
     A reaction: Rosen's shot at defining metaphysical necessity and possibility, and it looks pretty good to me. In my terms (drawing from Kit Fine) it is what is necessitated or permitted 'by everything'. So if it is necessitated by logic or nature, that's included.
'Metaphysical' modality is the one that makes the necessity or contingency of laws of nature interesting [Rosen]
     Full Idea: 'Metaphysical' modality is the sort of modality relative to which it is an interesting question whether the laws of nature are necessary or contingent.
     From: Gideon Rosen (The Limits of Contingency [2006], 02)
     A reaction: Being an essentialist here, I take it that the stuff of the universe necessitates the so-called 'laws'. The metaphysically interesting question is whether the stuff might have been different. Search me! A nice test of metaphysical modality though.
Sets, universals and aggregates may be metaphysically necessary in one sense, but not another [Rosen]
     Full Idea: It may be metaphysically necessary in one sense that sets or universals or mereological aggregates exist, while in another sense existence is always a contingent matter.
     From: Gideon Rosen (The Limits of Contingency [2006], 10)
     A reaction: This idea depends on Idea 18856 and 18857. Personally I only think mereological aggregates and sets exist when people decide that they exist, so I don't see how they could ever be necessary. I'm unconvinced about his two concepts.
The excellent notion of metaphysical 'necessity' cannot be defined [Rosen]
     Full Idea: Many of our best words in philosophy do not admit of definition, the notion of metaphysical 'necessity' being one pertinent example.
     From: Gideon Rosen (Metaphysical Dependence [2010], 03)
     A reaction: Rosen is busy defending words in metaphysics which cannot be pinned down with logical rigour. We are allowed to write □ for 'necessary', and it is accepted by logicians as being stable in a language.
Standard Metaphysical Necessity: P holds wherever the actual form of the world holds [Rosen]
     Full Idea: According to the Standard Conception of Metaphysical Necessity, P is metaphysically necessary when it holds in every possible world in which the laws of metaphysics (about the form or structure of the actual world) hold
     From: Gideon Rosen (The Limits of Contingency [2006], 10)
     A reaction: Rosen has a second meaning, in Idea 18856. He thinks it is crucial to see that there are two senses, because many things come out as metaphysically necessary on one concept, but contingent on the other. Interesting....
Non-Standard Metaphysical Necessity: when ¬P is incompatible with the nature of things [Rosen]
     Full Idea: According to the Non-Standard conception of Metaphysical Necessity, P is metaphysically necessary when its negation is logically incompatible with the nature of things.
     From: Gideon Rosen (The Limits of Contingency [2006], 10)
     A reaction: Rosen's new second meaning of the term. My immediate problem is with it resting on being 'logically' incompatible. Are squares 'logically' incompatible with circles? I like the idea that it rests on 'the nature of things'. (Psst! natures = essences)
10. Modality / A. Necessity / 6. Logical Necessity
Something may be necessary because of logic, but is that therefore a special sort of necessity? [Rosen]
     Full Idea: It is one thing to say that P is necessary in some generic sense because it is a truth of logic (true in all models of a language, perhaps). It is something else to say that P therefore enjoys a special sort of necessity.
     From: Gideon Rosen (The Limits of Contingency [2006], 02)
     A reaction: This encourages my thought that there is only one sort of necessity (what must be), and the variety comes from the different types of necessity makers (everything there could be, nature, duties, promises, logics, concepts...).
10. Modality / B. Possibility / 3. Combinatorial possibility
Combinatorial theories of possibility assume the principles of combination don't change across worlds [Rosen]
     Full Idea: Combinatorial theories of possibility take it for granted ....that possible worlds in general share a syntax, as it were, differing only in the constituents from which they are generated, or in the particular manner of their arrangements.
     From: Gideon Rosen (The Limits of Contingency [2006], 08)
     A reaction: For instance, it might assume that every world has 'objects', to which 'properties' and 'relations' can be attached, or to which 'functions' can apply.
10. Modality / C. Sources of Modality / 1. Sources of Necessity
Are necessary truths rooted in essences, or also in basic grounding laws? [Rosen]
     Full Idea: Fine says a truth is necessary when it is a logical consequence of the essential truths, but maybe it is a consequence of the essential truths together with the basic grounding laws (the 'Moorean connections').
     From: Gideon Rosen (Metaphysical Dependence [2010], 13)
     A reaction: I'm with Fine all the way here, as we really don't need to clog nature up with things called 'grounding laws', which are both obscure and inexplicable. Fine's story is the one for naturalistically inclined philosophers.
10. Modality / D. Knowledge of Modality / 4. Conceivable as Possible / a. Conceivable as possible
We can imagine being beetles or alligators, so it is possible we might have such bodies [Plantinga]
     Full Idea: We easily understand Kafka's story about the man who wakes up to discover that he now has the body of a beetle; and in fact the state of affairs depicted is entirely possible. I can imagine being an alligator, so Socrates could have had an alligator body.
     From: Alvin Plantinga (World and Essence [1970], III)
     A reaction: This really is going the whole hog with accepting whatever is conceivable as being possible. I take this to be shocking nonsense, and it greatly reduces Plantinga in my esteem, despite his displays of intelligence and erudition.
A proposition is 'correctly' conceivable if an ominiscient being could conceive it [Rosen]
     Full Idea: To a first approximation, P is correctly conceivable iff it would be conceivable for a logically ominiscient being who was fully informed about the nature of things.
     From: Gideon Rosen (The Limits of Contingency [2006], 05)
     A reaction: Isn't the last bit covered by 'ominiscient'? Ah, I think the 'logically' only means they have a perfect grasp of what is consistent. This is to meet the standard problem, of ill-informed people 'conceiving' of things which are actually impossible.
10. Modality / E. Possible worlds / 1. Possible Worlds / a. Possible worlds
Asserting a possible property is to say it would have had the property if that world had been actual [Plantinga]
     Full Idea: To say than x has a property in a possible world is simply to say that x would have had the property if that world had been actual.
     From: Alvin Plantinga (Transworld Identity or worldbound Individuals? [1973], I)
     A reaction: Plantinga tries to defuse all the problems with identity across possible worlds, by hanging on to subjunctive verbs and modal modifiers. The point, though, was to explain these, or at least to try to give their logical form.
Possible worlds clarify possibility, propositions, properties, sets, counterfacts, time, determinism etc. [Plantinga]
     Full Idea: The idea of possible worlds has delivered insights on logical possibility (de dicto and de re), propositions, properties and sets, counterfactuals, time and temporal relations, causal determinism, the ontological argument, and the problem of evil.
     From: Alvin Plantinga (Actualism and Possible Worlds [1976], Intro)
     A reaction: This date (1976) seems to be the high-water mark for enthusiasm about possible worlds. I suppose if we just stick to 'insights' rather than 'answers' then the big claim might still be acceptable. Which problems are created by possible worlds?
10. Modality / E. Possible worlds / 1. Possible Worlds / d. Possible worlds actualism
Plantinga says there is just this world, with possibilities expressed in propositions [Plantinga, by Armstrong]
     Full Idea: Plantinga rejects other possible worlds, but adds to our world an uncountable multitude of sets of propositions, each set a way that the world might have been, but is in fact not. (Roughly, for each Lewis world, Plantinga has such a set).
     From: report of Alvin Plantinga (The Nature of Necessity [1974]) by David M. Armstrong - Truth and Truthmakers 07.2
     A reaction: To me it seems as ontologically extravagant to postulate unexpressed propositions as to postulate concrete possible worlds. I think the best line is that there is just the actual world, with the possibilities implied in its dispositions.
Plantinga's actualism is nominal, because he fills actuality with possibilia [Stalnaker on Plantinga]
     Full Idea: Plantinga's critics worry that the metaphysics is actualist in name only, since it is achieved only by populating the actual world with entities whose nature is explained in terms of merely possible things that would exemplify them if anything did.
     From: comment on Alvin Plantinga (Actualism and Possible Worlds [1976]) by Robert C. Stalnaker - Mere Possibilities 4.4
     A reaction: Plantinga seems a long way from the usual motivation for actualism, which is probably sceptical empiricism, and building a system on what is smack in front of you. Possibilities have to be true, though. That's why you need dispositions in actuality.
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / a. Nature of possible worlds
A possible world is a maximal possible state of affairs [Plantinga]
     Full Idea: A possible world is just a maximal possible state of affairs.
     From: Alvin Plantinga (Transworld Identity or worldbound Individuals? [1973], I)
     A reaction: The key point here is that Plantinga includes the word 'possible' in his definition. Possibility defines the worlds, and so worlds cannot be used on their own to define possibility.
10. Modality / E. Possible worlds / 3. Transworld Objects / a. Transworld identity
What Socrates could have been, and could have become, are different? [Plantinga]
     Full Idea: Is there a difference between what Socrates could have been, and what he could have become?
     From: Alvin Plantinga (De Re and De Dicto [1969], p.44)
     A reaction: That is, I take it, 1) how different might he have been in the past, given how he is now?, and 2) how different might he have been in the past, and now, if he had permanently diverged from how he is now? 1) has tight constraints on it.
If possible Socrates differs from actual Socrates, the Indiscernibility of Identicals says they are different [Plantinga]
     Full Idea: If the Socrates of the actual world has snubnosedness but Socrates-in-W does not, this is surely inconsistent with the Indiscernibility of Identicals, a principle than which none sounder can be conceived.
     From: Alvin Plantinga (Transworld Identity or worldbound Individuals? [1973], I)
     A reaction: However, we allow Socrates to differ over time while remaining the same Socrates, so some similar approach should apply here. In both cases we need some notion of what is essential to Socrates. But what unites aged 3 with aged 70?
It doesn't matter that we can't identify the possible Socrates; we can't identify adults from baby photos [Plantinga]
     Full Idea: We may say it makes no sense to say that Socrates exists at a world, if there is in principle no way of identifying him. ...But this is confused. To suppose Agnew was a precocious baby, we needn't be able to pick him from a gallery of babies.
     From: Alvin Plantinga (Transworld Identity or worldbound Individuals? [1973], I)
     A reaction: This seems a good point, and yet we have a space-time line joining adult Agnew with baby Agnew, and no such causal link is available between persons in different possible worlds. What would be the criterion in each case?
If individuals can only exist in one world, then they can never lack any of their properties [Plantinga]
     Full Idea: The Theory of Worldbound Individuals contends that no object exists in more than one possible world; this implies the outrageous view that - taking properties in the broadest sense - no object could have lacked any property that it in fact has.
     From: Alvin Plantinga (Transworld Identity or worldbound Individuals? [1973], II)
     A reaction: Leibniz is the best known exponent of this 'outrageous view', though Plantinga shows that Lewis may be seen in the same light, since only counterparts are found in possible worlds, not the real thing. The Theory does seem wrong.
10. Modality / E. Possible worlds / 3. Transworld Objects / b. Rigid designation
Possibilities for an individual can only refer to that individual, in some possible world [Plantinga, by Mackie,P]
     Full Idea: Plantinga says for an individual to exist with certain properties in some possible world is simply for it to be true that, had that possible world obtained, that individual would have existed with those properties.
     From: report of Alvin Plantinga (The Nature of Necessity [1974]) by Penelope Mackie - How Things Might Have Been 5.1
     A reaction: This is intended to dissolve the problem of transworld identity, and is certainly a flat rejection of counterparts. I take the point to be that the individual is the key element in defining the possible world, so can't possibly be different.
10. Modality / E. Possible worlds / 3. Transworld Objects / c. Counterparts
The counterparts of Socrates have self-identity, but only the actual Socrates has identity-with-Socrates [Plantinga]
     Full Idea: While Socrates has no counterparts that lack self-identity, he does have counterparts that lack identity-with-Socrates. He alone has that - the property, that is, of being identical with the object that in fact instantiates Socrateity.
     From: Alvin Plantinga (Transworld Identity or worldbound Individuals? [1973], II)
     A reaction: I am never persuaded by arguments which rest on such dubious pseudo-properties. Whether or not a counterpart of Socrates has any sort of identity with Socrates cannot be prejudged, as it would beg the question.
Counterpart Theory absurdly says I would be someone else if things went differently [Plantinga]
     Full Idea: It makes no sense to say I could have been someone else, yet Counterpart Theory implies not merely that I could have been distinct from myself, but that I would have been distinct from myself had things gone differently in even the most miniscule detail.
     From: Alvin Plantinga (Transworld Identity or worldbound Individuals? [1973], II)
     A reaction: A counterpart doesn't appear to be 'me being distinct from myself'. We have to combine counterparts over possible worlds with perdurance over time. I am a 'worm' of time-slices. Anything not in that worm is not strictly me.
13. Knowledge Criteria / C. External Justification / 3. Reliabilism / a. Reliable knowledge
Maybe a reliable justification must come from a process working with its 'proper function' [Plantinga, by Pollock/Cruz]
     Full Idea: A modified version of reliabilism proposes that a belief is justified in case it is the product of a process that is working according to its 'proper function' in the environment for which it is appropriate.
     From: report of Alvin Plantinga (Warrant and Proper Function [1993]) by J Pollock / J Cruz - Contemporary theories of Knowledge (2nd) §1.5.4
     A reaction: Something might infallibly indicate something without that being its proper function (e.g. 'Red sky at night/ Shepherds' delight'). An inaccurate clock is fulfilling its proper function (telling the time), but not very well.
14. Science / D. Explanation / 2. Types of Explanation / j. Explanations by reduction
Six reduction levels: groups, lives, cells, molecules, atoms, particles [Putnam/Oppenheim, by Watson]
     Full Idea: There are six 'reductive levels' in science: social groups, (multicellular) living things, cells, molecules, atoms, and elementary particles.
     From: report of H.Putnam/P.Oppenheim (Unity of Science as a Working Hypothesis [1958]) by Peter Watson - Convergence 10 'Intro'
     A reaction: I have the impression that fields are seen as more fundamental that elementary particles. What is the status of the 'laws' that are supposed to govern these things? What is the status of space and time within this picture?
18. Thought / E. Abstraction / 1. Abstract Thought
The idea of abstract objects is not ontological; it comes from the epistemological idea of abstraction [Plantinga]
     Full Idea: The notion of an abstract object comes from the notion of abstraction; it is in origin an epistemological rather than an ontological category.
     From: Alvin Plantinga (Why Propositions cannot be concrete [1993], p.232)
     A reaction: Etymology doesn't prove anything. However, if you define abstract objects as not existing in space or time, you must recognise that this may only be because that is how humans imaginatively created them in the first place.
Theists may see abstract objects as really divine thoughts [Plantinga]
     Full Idea: Theists may find attractive a view popular among medieval philosophers from Augustine on: that abstract objects are really divine thoughts. More exactly, propositions are divine thoughts, properties divine concepts, and sets divine collections.
     From: Alvin Plantinga (Why Propositions cannot be concrete [1993], p.233)
     A reaction: Hm. I pass this on because we should be aware that there is a theological history to discussions of abstract objects, and some people have vested interests in keeping them outside of the natural world. Aren't properties natural? Does God gerrymander sets?
18. Thought / E. Abstraction / 2. Abstracta by Selection
The Way of Abstraction used to say an abstraction is an idea that was formed by abstracting [Rosen]
     Full Idea: The simplest version of the Way of Abstraction would be to say that an object is abstract if it is a referent of an idea that was formed by abstraction, but this is wedded to an outmoded philosophy of mind.
     From: Gideon Rosen (Abstract Objects [2001], 'Way of Abs')
     A reaction: This presumably refers to Locke, who wields the highly ambiguous term 'idea'. But if we sort out that ambiguity (by using modern talk of mental events, concepts and content?) we might reclaim the view. But do we have a 'genetic fallacy' here?
18. Thought / E. Abstraction / 5. Abstracta by Negation
Nowadays abstractions are defined as non-spatial, causally inert things [Rosen]
     Full Idea: If any characterization of the abstract deserves to be regarded as the modern standard one, it is this: an abstract entity is a non-spatial (or non-spatiotemporal) causally inert thing. This view presents a number of perplexities...
     From: Gideon Rosen (Abstract Objects [2001], 'Non-spat')
     A reaction: As indicated in other ideas, the problem is that some abstractions do seem to be located somewhere in space-time, and to have come into existence, and to pass away. I like 'to exist is to have causal powers'. See Ideas 5992 and 8300.
Chess may be abstract, but it has existed in specific space and time [Rosen]
     Full Idea: The natural view of chess is not that it is a non-spatiotemporal mathematical object, but that it was invented at a certain time and place, that it has changed over the years, and so on.
     From: Gideon Rosen (Abstract Objects [2001], 'Non-spat')
     A reaction: This strikes me as being undeniable, and being an incredibly important point. Logicians seem to want to subsume things like games into the highly abstract world of logic and numbers. In fact the direction of explanation should be reversed.
Sets are said to be abstract and non-spatial, but a set of books can be on a shelf [Rosen]
     Full Idea: It is thought that sets are abstract, abstract objects do not exist in space, so sets must not exist in space. But it is not unnatural to say that a set of books is located on a certain shelf in the library.
     From: Gideon Rosen (Abstract Objects [2001], 'Non-spat')
     A reaction: The arguments against non-spatiality of abstractions seem to me to be conclusive. Not being able to assign a location to the cosine function is on a par with not knowing where my thoughts are located in my brain.
18. Thought / E. Abstraction / 6. Abstracta by Conflation
Conflating abstractions with either sets or universals is a big claim, needing a big defence [Rosen]
     Full Idea: The Way of Conflation account of abstractions (identifying them sets or with universals) is now relatively rare. The claim sets or universals are the only abstract objects would amount to a substantive metaphysical thesis, in need of defence.
     From: Gideon Rosen (Abstract Objects [2001], 'Way of Con')
     A reaction: If you produce a concept like 'mammal' by psychological abstraction, you do seem to end up with a set of things with shared properties, so this approach is not silly. I can't think of any examples of abstractions which are not sets or universals.
18. Thought / E. Abstraction / 7. Abstracta by Equivalence
Functional terms can pick out abstractions by asserting an equivalence relation [Rosen]
     Full Idea: On Frege's suggestion, functional terms that pick out abstract expressions (such as 'direction' or 'equinumeral') have a typical form of f(a) = f(b) iff aRb, where R is an equivalence relation, a relation which is reflexive, symmetric and transitive.
     From: Gideon Rosen (Abstract Objects [2001], 'Way of Abs')
     A reaction: [Wright and Hale are credited with the details] This has become the modern orthodoxy among the logically-minded. Examples of R are 'parallel' or 'just as many as'. It picks out an 'aspect', which isn't far from the old view.
Abstraction by equivalence relationships might prove that a train is an abstract entity [Rosen]
     Full Idea: It seems possible to define a train in terms of its carriages and the connection relationship, which would meet the equivalence account of abstraction, but demonstrate that trains are actually abstract.
     From: Gideon Rosen (Abstract Objects [2001], 'Way of Abs')
     A reaction: [Compressed. See article for more detail] A tricky example, but a suggestive line of criticism. If you find two physical objects which relate to one another reflexively, symmetrically and transitively, they may turn out to be abstract.
19. Language / C. Assigning Meanings / 8. Possible Worlds Semantics
Plantinga has domains of sets of essences, variables denoting essences, and predicates as functions [Plantinga, by Stalnaker]
     Full Idea: The domains in Plantinga's interpretation of Kripke's semantics are sets of essences, and the values of variables are essences. The values of predicates have to be functions from possible worlds to essences.
     From: report of Alvin Plantinga (Actualism and Possible Worlds [1976]) by Robert C. Stalnaker - Mere Possibilities 4.4
     A reaction: I begin to think this is quite nice, as long as one doesn't take the commitment to the essences too seriously. For 'essence' read 'minimal identity'? But I take essences to be more than minimal, so use identities (which Kripke does?).
Plantinga's essences have their own properties - so will have essences, giving a hierarchy [Stalnaker on Plantinga]
     Full Idea: For Plantinga, essences are entities in their own right and will have properties different from what instantiates them. Hence he will need individual essences of individual essences, distinct from the essences. I see no way to avoid a hierarchy of them.
     From: comment on Alvin Plantinga (Actualism and Possible Worlds [1976]) by Robert C. Stalnaker - Mere Possibilities 4.4
     A reaction: This sounds devastating for Plantinga, but it is a challenge for traditional Aristotelians. Only a logician suffers from a hierarchy, but a scientist might have to live with an essence, which contains a super-essence.
19. Language / D. Propositions / 1. Propositions
Are propositions and states of affairs two separate things, or only one? I incline to say one [Plantinga]
     Full Idea: Are there two sorts of thing, propositions and states of affairs, or only one? I am inclined to the former view on the ground that propositions have a property, truth or falsehood, not had by states of affairs.
     From: Alvin Plantinga (Actualism and Possible Worlds [1976], 1)
     A reaction: Might a proposition be nothing more than an assertion that a state of affairs obtains? It would then pass his test. The idea that a proposition is a complex of facts in the external world ('Russellian' propositions?) quite baffles me.
19. Language / D. Propositions / 3. Concrete Propositions
If propositions are concrete they don't have to exist, and so they can't be necessary truths [Plantinga]
     Full Idea: Someone who believes propositions are concrete cannot agree that some propositions are necessary. For propositions are contingent beings, and could have failed to exist. But if they fail to exist, then they fail to be true.
     From: Alvin Plantinga (Why Propositions cannot be concrete [1993], p.230)
     A reaction: [compressed] He implies the actual existence of an infinity of trivial, boring or ridiculous necessary truths. I suspect that he is just confusing a thought with its content. Or we might just treat necessary propositions as hypothetical.
19. Language / D. Propositions / 4. Mental Propositions
Propositions can't just be in brains, because 'there are no human beings' might be true [Plantinga]
     Full Idea: If propositions are brain inscriptions, then if there had been no human beings there would have been no propositions. But then 'there are no human beings' would have been true, so there would have been at least one truth (and thus one proposition).
     From: Alvin Plantinga (Why Propositions cannot be concrete [1993], p.229)
     A reaction: This would make 'there are no x's' true for any value of x apart from actual objects, which implies an infinity of propositions. Does Plantinga really believe that these all exist? He may be confusing propositions with facts.
19. Language / E. Analyticity / 1. Analytic Propositions
'Bachelor' consists in or reduces to 'unmarried' male, but not the other way around [Rosen]
     Full Idea: It sounds right to say that Fred's being a bachelor consists in (reduces to) being an unmarried male, but slightly off to say that Fred's being an unmarried male consists in (or reduces to) being a bachelor. There is a corresponding explanatory asymmetry.
     From: Gideon Rosen (Metaphysical Dependence [2010], 10)
     A reaction: This emerging understanding of the asymmetry of the idea shows that we are not just dealing with a simple semantic identity. Our concepts are richer than our language. He adds that a ball could be blue in virtue of being cerulean.
26. Natural Theory / D. Laws of Nature / 4. Regularities / b. Best system theory
The MRL view says laws are the theorems of the simplest and strongest account of the world [Rosen]
     Full Idea: According to the Mill-Ramsey-Lewis account of the laws of nature, a generalisation is a law just in case it is a theorem of every true account of the actual world that achieves the best overall balance of simplicity and strength.
     From: Gideon Rosen (The Limits of Contingency [2006], 08)
     A reaction: The obvious objection is that many of the theorems will be utterly trivial, and that is one thing that the laws of nature are not. Unless you are including 'metaphysical laws' about very very fundamental things, like objects, properties, relations.
27. Natural Reality / F. Chemistry / 1. Chemistry
An acid is just a proton donor [Rosen]
     Full Idea: To be an acid just is to be a proton donor.
     From: Gideon Rosen (Metaphysical Dependence [2010], 10)
     A reaction: My interest here is in whether we can say that we have found the 'essence' of an acid - so we want to know whether something 'deeper' explains the proton-donation. I suspect not. Being a proton donor happens to have a group of related consequences.
28. God / B. Proving God / 2. Proofs of Reason / a. Ontological Proof
A possible world contains a being of maximal greatness - which is existence in all worlds [Plantinga, by Davies,B]
     Full Idea: Plantinga reformulates Malcolm's argument thus: 1) There is a possible world in which there exists a being with maximal greatness, 2) A being has maximal greatness in a world only if it exists in every world.
     From: report of Alvin Plantinga (The Nature of Necessity [1974], p.213) by Brian Davies - Introduction to the Philosophy of Religion 4 'b Descartes'
     A reaction: This is only Plantinga's starting point, which says nothing about the nature of God, but only that this 'great' being exists in all worlds. I would like to know why it is a 'being' rather than a 'thing'. Malcolm says if it is possible it is necessary.
29. Religion / D. Religious Issues / 3. Problem of Evil / b. Human Evil
Moral evil may be acceptable to God because it allows free will (even though we don't see why this is necessary) [Plantinga, by PG]
     Full Idea: Moral evil may be acceptable to a benevolent God because it is the only way to allow genuine free will, which may have a supreme value in creation (even if we are unsure what it is).
     From: report of Alvin Plantinga (Free Will Defence [1965], Pref.) by PG - Db (ideas)
29. Religion / D. Religious Issues / 3. Problem of Evil / d. Natural Evil
It is logically possible that natural evil like earthquakes is caused by Satan [Plantinga, by PG]
     Full Idea: Physical evil (e.g. earthquakes) may be attributable to a fallen angel (Satan), who is the enemy of God, and this is enough to retain the idea that God is omnipotent and benevolent, and yet evil exists.
     From: report of Alvin Plantinga (Free Will Defence [1965], III) by PG - Db (ideas)