Ideas of Alvin Plantinga, by Theme

[American, b.1932, Based at the University of Michigan, Calvin College, then at Notre-Dame.]

green numbers give full details    |    back to list of philosophers    |     unexpand these ideas    |    
5. Theory of Logic / F. Referring in Logic / 1. Naming / a. Names
Maybe proper names involve essentialism
     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.
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'?
     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
     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.
9. Objects / A. Existence of Objects / 4. Impossible objects
Plantinga proposes necessary existent essences as surrogates for the nonexistent things
     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.
9. Objects / A. Existence of Objects / 5. Individuation / a. Individuation
The 'identity criteria' of a name are a group of essential and established facts
     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?
     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
     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
     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
     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?
     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
     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
     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)
     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?
     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
     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
     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
Can we find an appropriate 'de dicto' paraphrase for any 'de re' proposition?
     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.
Expressing modality about a statement is 'de dicto'; expressing it of property-possession is 'de re'
     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
     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).
'De re' modality is as clear as 'de dicto' modality, because they are logically equivalent
     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 / 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
     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.
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
     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.
     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
     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
     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
     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?
     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
     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
     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
     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
     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
     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
     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'
     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.
18. Thought / E. Abstraction / 1. Abstract Thought
The idea of abstract objects is not ontological; it comes from the epistemological idea of abstraction
     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
     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?
19. Language / C. Assigning Meanings / 8. Possible Worlds Semantics
Plantinga has domains of sets of essences, variables denoting essences, and predicates as functions
     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
     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
     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
     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
     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.
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
     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)
     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
     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)