Friday, November 16, 2012

We've moved!

No, Metaphysical Values isn't going anywhere, but we've switched from Blogger to Wordpress. So point your browsers and RSS feeds to for all new Metaphysical and Valuable goodness from the crew of the Centre for Metaphysics and Mind at the University of Leeds!

Wednesday, October 24, 2012

How Can You Know You're Present?

I've posted a new paper online: 'How Can You Know You're Present?'


Some argue that non-presentist A-theories face an epistemic objection: if they were true, then we could not know whether we are present.  I argue that the presentist is in no better an epistemic position than the non-presentist.  In §1 I introduce the sceptical puzzle: I look at two ways in which the non-presentist could claim that our experiences give us evidence for our presentness, but find each wanting.  In §2, I argue that the puzzle also faces the presentist, and that a number of potential solutions either fail or are equally available to the non-presentist.  I conclude by defending one solution to the puzzle.

Monday, September 10, 2012

Is Lewis's ontology qualitatively or ideologically parsimonious?

David Lewis believes in lots of things.  He believes in human beings, and animals and plants; he believes in tables, and statues and universities; he believes in planets, and solar systems and galaxies.  And he believes in sets of such things, and sets of sets of such things, and sets which have only other sets as members.  And so on.  But so far, so mundane: there’s nothing there that plenty of philosophers don’t believe in.  But Lewis also believes in unicorns, and gods, and ghosts, and golden mountains.  Lewis thinks there’s a talking donkey who spends his days giving a completely accurate account of your life.  Lewis thinks that somewhere there is an infinite sequence of intrinsic duplicates of you doing a conga line.

That’s a pretty wild ontology.  Unless you’re a philosopher who believes in something that, as a matter of fact, just could not exist, then Lewis believes in everything you believe in and – chances are – an awful lot more.  How is this ontological extravagance to be justified?  Lewis offers two different answers to this justificatory challenge.  His more commonly mentioned answer is as follows.

The Cost-Benefit Response:
It is indeed a lavish ontology that is proposed.  It is a cost to accept that there are so many things: it is a pro-tanto reason not to accept the proffered theory that it posits so many things.  But this cost is outweighed by the benefits afforded by the theory.  If it is true then it provides for a reduction of the modal, an ontological identification of propositions and properties with sets of individuals, and so on.  These benefits outweigh the admitted ontological costs.  So on the balance of costs versus benefits, the theory should be accepted, and the lavish ontology embraced.

Here Lewis is admitting that his ontology comes at a price, but that it is a price worth paying.  But elsewhere he refused to admit that there is even a price to be paid.  He offers instead the following answer to the justificatory challenge.

The No-Cost Response:
The extra things postulated are just more things of the same kind that we all already believed in.  To believe in more kinds of thing is a cost, but to believe in more tokens of a kind of thing you already believe in is no additional cost.  Thus the postulation of this additional ontology is not even a cost that needs to be paid.  It is not even a pro-tanto reason not to accept the proffered theory that it posits so many things, given that they are things of a kind with things postulated by the theory’s salient rivals anyway.

The former response sees the ontology as a cost to be outweighed, the latter doesn’t even acknowledge it as a cost.  Lewis distinguishes between a principle of quantitative parsimony which tells you to minimise the number of things postulated, and principle of qualitative parsimony which tells you to minimse the number of kinds of things postulated.  He admits the latter as a good rule, but doesn’t think he is breaking it; he admits to breaking the former, but doesn’t recognize it as a good rule to be obeyed.

I’m not interested here in which response to the justificatory challenge Lewis would do better to rely on.  My question here is: is Lewis correct when he says, in the No-Cost Response, that his theory is a pro-tanto offense only against quantitative parsimony and not against qualitative parsimony?

Joseph Melia argued that Lewis was wrong: that his ontology sinned against qualitative parsimony as well.  Indeed, that Lewis’s ontology maximally sins against qualitative parsimony, since it admits the existence of things for any kind of thing that there could be.  The only way to do worse on qualitative parsimony would be to believe in some kinds of thing that couldn’t exist.  But provided that we’re only concerned with theories that refrain from postulating impossibilia, Lewis’s proposed ontology is maximally qualitatively unparsimonious: for every kind of thing there could be, Lewis believes in things of that kind.

John Divers responds on Lewis’s behalf.  Lewis believes in sets and individuals, the end.  Actuality consists of individuals and sets, and the admission of the reality of logical space requires merely the postulation of more individuals and sets.  Thus the number of kinds of thing you need to acknowledge by accepting Lewis’s ontology is the same as what we’d need to acknowledge to give a good account of actuality anyway: two.  Thus Lewis does not sin against qualitative parsimony, as he claimed.

How are we to judge this dispute between Divers, on behalf of Lewis, and Melia?  It comes down, seemingly, to a really thorny issue: at what level do we draw the kinds?  Sure, at one level Lewis is merely asking us to believe in things of a kind with what we already believe: individuals (we all believe in those, right?), and the sets that you get by taking those individuals as ur-elemete (and most of believed in sets anyway – and if you don’t, well just believe in Lewis’s ontology minus the sets!).  But on another level, Lewis isn’t just introducing us to new individuals, he’s introducing us to new kinds of individuals.  He believes in unicorns; so there’s a kind of thing – unicorn – that Lewis is asking us to believe in that we didn’t already believe in.

At one level, everything is of a kind: entity.  Read thus, the rule of qualitative parsimony only ever tells us to (ceteris paribus) choose a theory that doesn’t postulate anything at all over one that does: it will never select between theories that each say that there is something.  That’s pretty useless.  At the other extreme, there’s a kind for every way for things to be: hence, a kind F for every predicate F (at least, every satisfiable predicate).  Read thus, the rule of qualitative parsimony will collapse into the rule of quantitative parsimony, for every new token thing you admit will also be to admit a new kind of thing.

For there to be an interesting rule of qualitative parsimony, we have to find a middle level: a way of dividing things into kinds such that it isn’t automatic that everything is of a kind nor that no two things are of a kind.  (Or better: that for any two things, there’s a kind that one falls under that the other doesn’t.)  But then the question is: at what level do we draw the kinds?  How can we do this in a principled manner?  Divers and Melia draw the kinds at different levels, but who is right?  What facts about reality even speak to one way of drawing the kinds as the correct way (or at least, the correct way for the purposes of weighing theories with respect to qualitative parsimony)?

If you believe in ontological categories, you’ve got an answer: draw the kinds at the level of the categories.  So the principle of qualitative parsimony amounts to saying: (ceteris paribus) choose the theory that postulates the fewest ontological categories.  So take someone like E.J. Lowe, who thinks the things in reality divide into four ontological categories: the substantial particular, the substantial universal, the non-substantial particular, and the non-substantial universal.  On the current proposal, Lowe should view the principle of qualitative parsimony as telling him: believe in whatever kinds of thing you like provided the things fall into one of these four categories – but (ceteris paribus) don’t accept a theory that postulates a fifth category of thing, and (ceteris paribus) prefer a theory that postulates fewer categories of thing.

But personally, I don’t find this very helpful.  The same problem as before just comes back at a different point.  When I think of Lowe’s four ontological categories (e.g. – I’m picking on Lowe’s view, but I think the same thing about every proposal on ontological categories that I’ve encountered), I simply wonder why that is the right way to divide things up.  By a non-substantial universal, Lowe means an Armstrongian universal like redness; by a non-substantial particular he means a trope, like the redness of this postbox.  Why isn’t that one ontological category: property?  By a substantial particular he means kinds like electron.  Why aren’t the universals, tropes and kinds all part of the same ontological category: abstracta?  This is just exactly the same problem as before: where to make the divisions.  But instead of asking directly where to make the divisions for the purposes of qualitative parsimony, we’re assuming we make the divisions at the level of ontological categories and instead asking where to make those divisions instead.  I don’t find the detour illuminating, having as little an intuitive grasp of where the ontological categories are as I have of what matters with respect to qualitative parsimony.

I suggest a rethinking of the principle of qualitative parsimony.  I think we should qualitative parsimony as derivative on a more fundamental norm of theory choice: ideological parsimony.  Qualitative parsimony is a virtue just insofar as it facilitates ideological simplicity.

So consider a debate between a compositional nihilist and a universalist.  The former, let us suppose, claims an advantage with respect to qualitative parsimony, since the universalist believes in a kind of thing – a complex object – that the nihilist does not believe in.  The universalist responds, suppose, that she is at no disadvantage with respect to qualitative parsimony since she is only believing in more things of the same kind the nihilist believes in: concrete individuals.  I think that it’s fruitless to try and settle whether, for the purposes of theory choice by qualitative parsimony, mereologically simple concrete individuals are of a kind with mereologically complex complex individuals.  In some sense, complex objects are a new kind of thing, and in another sense they aren’t: the question we should be asking, I think, is whether their admission requires more ideological resources.  And in this case, it plausibly does, because while the nihilist can eschew the ideology of mereology, the universalist needs to admit amongst their fundamental ideological primitives some mereological notion.  Thus, as Ted Sider (inspired by Cian Dorr) argues, there is a pro tanto reason to be compositional nihilists, for it minimizes the ideological complexity in reality.  I think that a drive to ideological simplicity is really what’s behind the drive to qualitative parsimony, and this lets us get a grip on what the relevant level of kinds is: admitting the Xs constitutes admitting a new kind of thing, in the relevant sense, when describing reality if there are Xs requires greater primitive ideological resources than describing reality does if there are no Xs.

In that case, it doesn’t look too good for Lewis, for even though he’s only introducing us to new individuals and sets of individuals, as Divers says, it nonetheless looks as though we’re going to need new ideological resources to describe those individuals.  We’re going to need new primitive predicates to describe things that instantiate alien properties since, ex hypothesi, those predicates aren’t definable in terms of a logical construction of actually instantiated predicates.  We’re going to need new spatio-temporal ideology to describe those worlds where things aren’t related spatio-temporally but rather are related in a manner ‘analogous’ to spatio-temporal relatedness.  We’re going to need new ideology to describe the ectoplasm ghosts the absence of which allows actuality to be a physicalistically acceptable world.  So it’s looking like Melia is right: the postulation of these new kinds of thing is a sin against qualitative parsimony.  Divers is right that it’s just more individuals, but that doesn’t matter, since they are individuals that are not describable just with the ideological resources we would have needed to describe actuality.

But whether this is really so depends on another question that I don’t know the answer to.  When judging what ideological resources you need, do you only count what you need to describe what there is, or do you need ideology enough to describe the ways things could have been?  For Lewis of course, there’s no difference: what there is includes all that there could have been.  But what about for those of us who think that how things are as a whole could have been different?  Does the mereological nihilist who thinks there could have been composite objects but there just happen not to be get to claim an ideological advantage over the universalist, or does one need to reject the very possibility of composition to claim such an advantage?

Parity with ontological parsimony suggests that you should only count the ideology you need to describe things as they are.  After all, no one would think that it is a sin against ontological parsimony to think that there could have been immaterial minds; it’s only believing in them that counts against ontological parsimony.  In which case, why should the possibility of having to describe things using some mereological notion matter: it only matters whether describing things as they are requires such notions.

Nonetheless, I can’t shake the feeling that ideological parsimony is different from ontological parsimony in this respect.  That the contingent mereological nihilist is at no advantage over the universalist, only the necessitarian nihilist.  After all, a theory of reality is not complete without a description of how things could have been: so your fundamental theory of reality will have to talk about what could have occurred but doesn’t – and so if there could have been complex objects, you will need to invoke mereological notions to describe that possibility.  So you can’t completely eschew speaking mereologically: your fundamental theory will still need its mereological primitives, even if it only ever uses them within the scope of a modal operator.  I find it intuitive that in that case you still incur the ideological cost: you still have to see reality in mereological terms, even if just to say that actuality is mereologically less complex than it could have been.  To really not have anything to do with the ideology of mereology you must not need to resort to it at any point in your description of reality – whether of how things are or how they could be – you must be a necessitarian nihilist.  (I’m assuming here that how things could be really is a part of the theory of reality.  If you were an expressivist or other kind of anti-realist about the modal I suppose you would deny this.  But since those views are false . . .)

If that is right, then things start to look better for Lewis.  In believing in possibilia, Lewis just thinks that the story of how things are and could be is the story of how things are unrestrictedly: so for him, the ideology needed to describe how things are, simpliciter, is the ideology required to describe how things actually are and how they could have been.  But if we were committed anyway to the ideological resources needed to describe both reality and the possible ways reality could be, this won’t be an ideological expansion, and Lewis won’t be sinning against ideological parsimony – hence against qualitative parsimony – after all.

Friday, August 17, 2012

Temporary Job at Leeds

Leeds is advertising a 12 month lecturership starting mid September.  You must have some experience in teaching formal logic.  Note the very tight deadline: applications must be in by Aug 30th.

Saturday, June 16, 2012

Changing Truthmakers

I've posted a new paper, 'Changing Truthmakers'.  It's a reply to a paper by Jonathan Tallant and David Ingram, which is in turn a reply to my 'Truthmaking for Presentists'.

It's about how we can stop truthmakers for tensed truths changing, so as to ensure the validity of theorems of tense logic like 'If it's now the case that p, it always will be the case that it was the case that p'.  And I get to talk a bit about hypertime, which is always cool!

Sunday, June 10, 2012

The Time-Travelling Trinitarian God

After having too much caffeine I started thinking about the metaphysics of the Trinity, for no immediately obvious reason.  The following is crazy, but maybe kinda fun too?  Well, here goes nothing . . .

It’s time t0: the very first instant there is.  At this instant, there exists God the Father and God the Son.  One event occurs at this instant: God the Son is begotten of God the Father.

What is the relationship between God the Father and God the Son?  Well, we already have part of the story: the latter is begotten of the former.  Is there anything else we can say at this point?  One might be tempted to conclude that we know also that they are numerically distinct, since nothing is begotten of itself.

Certainly, this claim of distinctness seems to fit well with some of the things God the Son goes on to say.  He says, after all, that God the Father is greater than he is: and surely nothing is greater than itself!  Other things he says seem to at least conversationally imply that he is distinct from God the Father, even if they don’t logically entail it.  He says, for example, that no-one can come to the Father except through him (the Son): it would be less misleading to simply say ‘No-one can come to me except through me’ if that’s what this amounted to, as it surely would were the Father and the Son the same being.  All in all then, it seems like there is good reason to conclude that we have two things here: the Father and the Son.

Unfortunately, the Son also says some things that suggest that he is not distinct from the Father.  He says that he and the Father are one.  He doesn’t elaborate too much on what he means (he has a fondness for the cryptic!), but the smart money is on the claim that he’s saying they are of one essence.  And we have good metaphysical reasons for thinking that if A and B are of one essence, they are numerically identical.  For surely it is part of the essence of A that it is A and not some other thing.  And if B is not A then it is certainly not part of B’s essence that it is A.  So if A and B are distinct then they are not of one essence.  We also have theological reasons for thinking that the Father and the Son are identical, for we believe each of (i) The Father is divine, (ii) The Son is divine, (iii) For all x, if x is divine then x is a god, and (iv) There is exactly one god.  And (i)-(iv) together entail that the Father is the Son.

So we’re in a quandary: the story so far pulls in two directions, some things indicating that the Father and the Son are distinct, some things indicating that they are identical.  Let us now see how the story progresses.

God the Father is really powerful.  In fact, he can do anything metaphysically possible.  This is true at time t0, and it remains true for ever.  He never loses any of his powers; and of course he never gains any, since he can already do anything possible (and that’s as powerful as it’s possible to be).  God the Son, on the other hand, starts off life at t0 far less powerful.  (Hence his claim that the Father is greater than he is.)  But unlike the Father, the Son grows in power over time until, at the very last moment of time, tz, he is himself capable of doing anything metaphysically possible.  One of the things he can do at tz is travel in time, this being metaphysically possible.  And so he does: he travels back to t0, at which point he calls himself God the Father and begets the earlier less powerful version of himself, calling him God the Son.

This is the story of a time-travelling deity.  At the beginning of time there is only God: but there are two ‘versions’ of him – there is the all powerful being he becomes at the end of time, who travelled back in time to the first moment, and there is the less powerful being that he started out as, who was begat by his more powerful future self after he travelled back in time.

I am not claiming that this is how the world is.  But I think it is possible, and that if it is true then the data we started with is accounted for.  Thus, I think we have here a metaphysical model that vindicates the orthodox Christian understanding of the relationship between God the Father and God the Son.

Consider the first puzzle: how can the Son be the Father if the former was begotten of the latter?  Well, if time travel is possible, cases of self-creation just aren’t that puzzling.  Let’s suppose that a man undergoing a sex change would be capable of giving birth.  So suppose I now, in 2012, travel back in time to 1979, wait a year and get a sex change and then travel back in time to 1979 again; at that point my male self that came back from 2012 can mate with my female self who came back in time from 1980, who will then give birth to infant me in 1980, who will grow up to back in time in 2012.  This scenario is perfectly consistent, and it involves me creating myself.  So there’s nothing impossible about God going back in time and begetting his earlier self.

It’s also clear that if this is how things are, God the Son’s declaration that the Father is greater than he is is a perfectly sensible thing to say.  If I go back in time to 1980 then I can look at infant Ross and truly say ‘He is me’, but I can also sensibly say ‘I am taller than he is’.  In general, if something that changes across time travels back in time to a time when it was different, then we can sensibly contrast how its later self is with how its earlier self is, even though they are the same thing.  Thus the Father, God’s later self, can sensibly be said to be greater than the Son, his earlier self, despite them being the same being.

Similarly, if I go back in time to protect my infant self in the cradle, I can sensibly say ‘Nobody gets to him except through me’.  And it’s simply not more conversationally informative for me to say ‘Nobody gets to him except through him’, despite the fact that I am he.  Since I can sensibly contrast my later self with my earlier self – my later self is bigger and stronger – then I can sensibly say that it is my later self protecting my earlier self and not my earlier self protecting my earlier self, despite the fact that my later self is my earlier self.  Likewise, if it requires a being like us in some respects to bring us to a being who is so far beyond us in power, then the Son can sensibly say that it is only he that can bring you to God the Father; and it would not be better for him to say that it is only the Father that can bring you the Father, despite the fact that he is the Father.

Note that I’m not claiming that these contrastive claims are true, only that they are sensible claims to make in those circumstances.  Whether or not they are true depends on some tricky issues concerning persistence and change.  It’s a prima facie puzzle if A is F and travels back in time to a moment when it is not F, for then it seems that at that time A is F and not F – contradiction!  What should we say about this puzzle?  It’s obviously similar to the familiar problem of temporary intrinsics – how can David be hairy at one time and not hairy at some other time (once he’s lost his hair), given that it’s one person here, and nothing differs from itself?  But in our case, it’s not another time: it’s the same time, because the A that is F has gone back to meet the A that is not F.

Here are some common responses to the problem of temporary intrinsics.  The perdurantist thinks that the thing that is hairy is not David, but rather a temporal part of David, and the thing that is not hairy is a different temporal part of David.  Since these temporal parts are numerically distinct, there is no puzzle in their being different in properties.  When David says in his early life that he is hairy, he speaks truly, because the truth-conditions of his utterance are that the temporal part that makes the utterance is hairy.  If this is the correct response to the problem of temporary intrinsics, it carries over straightforwardly to the time travel case.  The later version of A that travels back to meet its earlier self is really a different thing: it is a later temporal part, and it is meeting its earlier temporal part, and so there is no puzzle in one being F and the other not being so.  On this view, I speak truly when I travel back and say that I’m taller than my infant self: the temporal part that makes that utterance is taller than the temporal part that’s in the cradle.  Similarly, the Son speaks truly when he says that the Father is greater than he is: the Father is God’s later temporal part, and does indeed have more powers than the Son, who is God’s earlier temporal part.

But suppose perdurantism is false.  The two most common endurantist solutions to the problem of temporary intrinsics need modification if they are to handle the time travel case.  On one view, things are incapable of changing with respect to their monadic properties, and what we normally think of as a thing changing with respect to a monadic property is in fact it standing in a certain kind of relation to some times but not others: so while it looks like David is hairy simpliciter at one time and not at another, in fact David is never hairy or not hairy simpliciter but rather bears the being hairy relation to some time but fails to bear it to a later time.  But if we’re to allow for the time travel case we will have to say that apparent monadic properties are not two place relations between an enduring object and a time, but rather three place relations between an enduring object, a time, and a place.  So when A travels back to meet earlier A, it is true simpliciter that A bears being F to time t and place L1 and true simpliciter that it fails to bear that relation to time t and place L2.  (L1 being the place the future version ends up at t, L2 being the place the earlier version is at that time.)

What are the truth-conditions for ‘A is taller than B at time t’ if height properties are really three place relations between an object a time and a place?  There are various options: perhaps it’s true iff every height relation A bears to some place at t is greater than every height relation that B bears to some place at t; perhaps it’s true iff there’s a mapping that takes you from the height relations A bears to some place at t to the height relations B bears to some place at t (leaving no relations out) and which maps greater relations onto lesser ones; and there are other options.  But if either of those suggestions are correct, it would turn out to be false when I go back in time and say, looking at my infant self, that I am taller than he.  For if A=B then they will bear the same height relations to places at a given time, and so it’s hard to think of a sensible option on which it could come out true that A is taller than B at a time.

Another common endurantist option is to hold on to the thought that apparent monadic properties are just that, but to deny that such properties are ever had simpliciter: instantiation of such properties is always relative to a time.  So David has being hairy a certain way (i.e. relative to the earlier time) but he lacks that property some other way (relative to the later time).  The natural extension of such a view to allow for time-travel cases is to relativise instantiation to both time and place.  And it’s easy to see why, for similar reasons to those above, this is going to lead to a similar conclusion: that I won’t speak truly when I look at my infant self and say that I am taller than he.

So return to God the Son’s assertion that God the Father is greater than he is.  If God is a perduring object then there’s no problem in this being straight-forwardly true.  At t0 there are two distinct things: the earlier temporal part of the spacetime worm that is God and the later temporal part of God – the former lacks omnipotence, the latter has it, and the utterance the former makes is thereby true.  If God is an enduring object, however, it looks like the Son’s utterance is false: for everything we can say about the Son’s powers at t0 will also be things we can say about the Father’s powers at t0.

I don’t want to take a stand on the perdurantism versus endurantism debate here.  What I want to argue is that each option adequately accounts for the data.  The perdurantist option does so by rendering the Son’s utterances concerning his relationship to the Father straightforwardly true.  The endurantist option renders some of them false; but I think this shouldn’t worry us, because the Son’s claims are still sensible things to say in these circumstances, and this is all we should need to secure.

If I’m an enduring object and travel back to meet my infant self, then I am in 1980 twice over: I am bi-located at that time.  Suppose I’m trying to locate my infant self, who is in a hospital in Glasgow, but I don’t know how to get there from where my adult self is (Leeds, let us suppose).  You’re trying to help me get there and you ask ‘Are you in Glasgow?’.  I can truly answer ‘yes’.  I am in Glasgow, for I am in two places, and one of them is in Glasgow.  But while true, it would be utterly unhelpful and disingenuous for me to answer in the affirmative: my speaking thus would not help you help me in my plans to bring my adult self to my infant self.  And while it would be false, it would nevertheless be completely helpful and appropriate to say ‘No, I’m not in Glasgow, I’m in Leeds’.  That’s false, because I’m both in Glasgow and in Leeds; but it’s a good thing to say because it communicates to you the information that you want: that the location I have in virtue of my adult self having travelled back to this time is in Leeds, even though I also have a location in Glasgow in virtue of my also having been an infant at this time.  Likewise, when I find my infant self and claim to be taller than he is, what I say is strictly speaking false: everything true of him is true of me, for we are identical, and so every height relation he bears to a place at this time (or every way he has a height) is also a height relation I bear to a place at this time (or is also a way I have a height).  Nonetheless, the false contrastive claim is a sensible thing to say and can impart useful information: it tells you that the height I have in virtue of having travelled back to this time as an adult is greater than the height I have in virtue of having been born at this time.

God the Son wasn’t speaking to metaphysicians, he was speaking to the folk.  The data that needs to be recovered is that he said something good: something that would impart good, true, information to his listeners.  Even given endurantism, his utterance does this on the time-travel story, despite being strictly speaking false.  Everything you can say about God the Son’s powers at t0 you can say about God the Father’s powers at t0, since they are the same thing.  Nonetheless, you learn something true and useful from the Son’s utterance that the Father is greater than he is: you learn that it is in virtue of this one being having come back in time after having changed that he is omnipotent at that time, and in virtue of him having begotten his earlier self at that time that he lacks omnipotence at that time.  The Son could have conveyed this information with a literally true utterance if he had spoken in a more metaphysically perspicuous manner; but since he was speaking to the folk and not to a select audience of metaphysicians, it’s perfectly understandable why he didn’t.

The Son’s utterance that no-one can come to the Father except through him is true.  As would have been the utterance that no-one can come to the Father except through the Father.  But while both true – and while in some sense they both say the same thing – the latter is not as good a thing to say as the former.  For the latter claim fails to impart the vital information conveyed by the former: that it is virtue of God having had his earlier properties that he is able to bring you to a being that is so far beyond you, namely the all-powerful being he becomes.  So it’s no surprise that the Son makes the former pronouncement and not the latter: far from being less informative, it is in fact more so.

And so I think we have a model of the relationship between the Father and the Son that adequately accounts for our initially recalcitrant data.  But what of the third member of the Trinity, the Holy Spirit?  Well, it would be easy to account for the third member in just the same way: have God travel in time twice.  Recall the story of me giving birth to myself: at the time I was born there were three versions of me about (the father, the mother after I had a sex change, and the child the first two versions of me gave birth to), because I travelled back to that time twice as well as being born there.  Thankfully, the Bible is pretty silent on the relationship between the Holy Spirit and the Son and the Father, so you can fit it in as you wish once you’ve got the general recipe.

Let me close by considering an objection.  One might object at the very idea of God starting out life as a limited being and only growing to be omnipotent over time.  That might be thought to violate the claim that it is essential to God’s very nature that he is omnipotent.  Care is needed here, however.  It’s perfectly compatible with the above account that God is essentially omnipotent in that it is of his essence that he grow to become omnipotent.  And God is around and omnipotent right from the beginning of time, remember.  He’s also around and limited at that time, but he’s omnipotent at that time as well, because his later self travelled back to then.  And this might also be of God’s essence: perhaps he has to so travel back (after all, if he didn’t travel back to beget himself, where would he come from?).  And so it’s compatible with the proposed account that God is essentially such as to become omnipotent, and that he is essentially such as to be omnipotent at all times.  What it’s not compatible with is the claim that he’s essentially such as to be never not omnipotent, since on this account he is sometimes both omnipotent and not omnipotent.  I doubt our intuitions regarding God’s essence are so fine-grained that this is determinately what we have in mind when he say that he is essentially omnipotent, so I’m unconcerned about biting this bullet.