Theistic Notebook

March 28, 2011

An Intro to the Philosophy of Religion Ch. 5 (Ontological Arguments)

Intro to the Philosophy of ReligionAnselm, Descartes and objections

1. God is the greatest conceivable being.
2. God exists in the understanding.
3. To exist in reality is better than merely to exist in understanding.
4. Thus, if God exists merely in the understanding, then we can conceive of something greater than God, namely a being just like God, but who also exists.
5. But it is impossible to conceive of a being that is greater than the greatest conceivable being.
6. Thus it is impossible that God exists merely in the understanding.
7. Thus God exists in reality as well as in the understanding.
8. Thus God exists.

Rea and Murray find Anselm’s original formulation of this argument, as it appeared in his famous work the Proslogion, to be problematic.  What exactly are we to make of the second premise?  They refer to Descartes’ version of the argument for help, and take notice of his slightly different notion of God as a being containing all perfections rather than Anselm’s greatest conceivable being.  They reconstruct the argument as follows:

1. God is the greatest possible being (GPB).
2. The GPB possesses every perfection that would make a being great.
3. Existence is a perfection that would make a being great.
4. God possesses existence […thus God exists]

Gaunilo of Mamoutier penned a famous objection to Anselm’s argument, entitled “In Defense of a Fool,” where he facetiously replaces “God” with  “Lost Island” as a proof for the existence of the greatest conceivable island; his objection aims to show how Anselm’s argument leads to absurd conclusions.  But does the argument really work when we plug in other greatest conceivable things?  That depend on what makes something the greatest of its kind.  How many miles of beach would the greatest conceivable island have (100, 1,000, 10,000)?  Certain types of perfection (such as the greatest number of miles of beaches) don’t have an intrinsic maximal value, and thus Mamoutier’s objection hasn’t identified a valid candidate for use in Anselm’s argument .  Not so fast though, this objection might cut both ways if some of God’s own great-making properties don’t have an intrinsic maximal value (e.g., God ‘s being perfectly loving).

But is existence a property at all, much less (or should I say much more) a great-making property?  Kant answered in the negative, maintaining that existence is always presupposed for a thing which is propertied (more simply, Kant maintains that “my cat is black” presupposes “my cat exists”). [1]  Murray and Rea don’t see why a precondition (for ascribing other properties) can’t itself be a property.  For example: taking up space is a precondition for having the property of being red, but taking up space is itself a property.  Their response seems reasonable, except that existence is the precondition for all other properties (or so Kant argues).  But this fact alone doesn’t show that existence isn’t itself a property (or at least I can’t see how it does).

The third and most popular, potent objection to this argument is simply that is begs the question; it assumes God exists before in the premises.  After we modify the first premise to avoid this objection, it’s hard to see how we can reach any satisfactory conclusion.  For instance, if the first premise reads “For anything to count as God,  that thing would have to possess existence” we can follow the argument through and see how this is undesirable.  Rea and Murray, and many other philosopher, think the traditional argument fails to avoid this third objection.

The Modal Ontological Argument
A new rendition of this argument has surfaced via recent work in an area of philosophy known as modal logic.  Modal logic deals with possibility and necessity.   Rea and Murray define a possible world as “a comprehensive description of the way the universe might be … the maximally comprehensive description of our universe is the actual world.”  Contingent beings only exists in some possible worlds but not others.  A necessary being, if it exists, would exist in all possible worlds.  A being possesses a property necessarily if it has that property in all (relevant) possible worlds (Plantinga refers to the properties that a person has necessarily as their “essence” ).  For example, Arnold Schwarzenegger is 6 feet tall ascribes a property to Arnold, but Arnold could be 5 feet tall in another possible world.  On the other hand, Arnold Schwarzenegger is a person ascribes a property to Arnold that he holds in all (relevantly) possible worlds.  Having laid the ground for understanding modal logic, the modal ontological argument is presented as follows.

5.20 God is the greatest possible being.
5.21 The greatest possible being is one that possesses all perfections necessarily.
5.22 Necessary existence is a perfection.
5.23 It is possible that the greatest possible being exists.
5.24 If it is possible that the greatest possible being exists, then that being exists necessarily.
5.25 God exists necessarily.
5.26 God exists.

My rough attempt at stating it with a little less precision and a little less jargon:
If we can show that the great possible being exists is true in at least one possible world, then we have shown that God exists.  Why?  Since the greatest possible being would possess all perfections necessarily (see premise 5.21), this means it would have those perfections in every possible world where it exists.  Since necessary existence (that is, existence in all possible worlds) is a perfection, then it follows that the greatest possible beings exists in all possible worlds is true in all possible worlds if true in any possible world.  Since the actual world (the one we live in) is one of those possible worlds, it follows that God exists in the actual world.

Premise 5.23 is susceptible to refutation.  For instance, some philosophical theologians think that the concept of a greatest possible being entails a contradiction, thus disqualifying God from existing in any possible world.  In other words, if a perfect being is shown to be conceptually incoherent, this argument fails.  A more modest critic might simply insist that we withhold judgement on this argument until we have resolved all the apparent contradictions in philosophical theology.  But a rebuttal can be given to both critics here.  Since premise 5.23 asserts the possibility that the greatest possible being exists, then the ontological defender’s response to conceptual incoherence should be to adjust the concept of the greatest possible being to get in line with what is possible.  Does omnipotence and impeccability entail a contradiction?  No problem, just tweak the concept to remove the contradiction.

One final objection to be raised is that necessary existence is impossible (premise 5.22).  Rea and Murray don’t think that any convincing arguments have been offered in this direction. [2]

Alvin Plantinga, in God, Freedom and Evil (1977), proceeds meticulously through the details of Kant’s objections in a section entitled, “The Irrelevance of Kant’s Objection.” Pdf is available here.  Chris Heathwood wrote a reply entitled, “The Relevance of Kant’s Objection.”
2 See Edward Feser’s summary of Plantinga’s ontological argument here.  Also, see William F. Vallicella’s articles on broadly logical necessity (he disagrees with many philosophers who say that conceivabality entails possibility)  as well as A Modal Ontological Argument and an Argument from Evil Compared.

March 22, 2011

An Intro to the Philosophy of Religion, Ch. 4

Intro to the Philosophy of ReligionThe nature of faith
Murray and Rea offer their account of faith as follows:

“…to say that a person S has faith in proposition p is to say that S believes p despite the fact that (a) there are alternatives to p that are compatible with whatever evidence supports S’s belief that p, and b) there is genuine and somewhat weighty evidence in favor of one or more of those alternatives.”

Since they classify faith as a kind of belief, there can be degrees of faith just as there can be degrees of belief (credences).  In addition, their definition of faith implies that faith can be judged as rational or irrational depending on the evidential context.  But what counts as evidence?

Reliabilism and Evidentialism
The evidentialist maintains that the rationality of a religious belief (merely) depends on the degree to which the belief is supported by arguments–in other words, only propositional evidence counts.  On the other hand, the reliabilist maintains that a belief is rationally held when (a) produced by reliable, properly functioning cognitive faculties, and (b) unaccompanied by overriding reasons to deem the belief irrational.  This implies that experiential evidence (e.g., religious experience) can justify a belief under the right conditions.  Properly basic beliefs are ones which can be justified or held without relying on other beliefs; for instance, perceptual belief is held on the basis of perceptual experience.  Likewise, Rea and Murray think that religious experience might justify a religious belief so long as it satisfies the criterion mentioned above.  What kinds of evidence might defeat our confidence in religious experiences?

Religious disagreement
Just as scientific theories explain sensory experience, Rea and Murray construe religious theories as collective attempts to explain religious experience.  A problem comes to light here: while scientific theories enjoy a fair level agreement, most religious theories are quite the opposite.  In light of this disagreement, one might ask some questions:

1. Do religious theories track truth about reality?

2. Are the arguments for any religious positions successful?

3. If not, should religious belief and practice be abandoned?

The religious skeptic generally replies in the negative to the first two questions, but affirms the last one.  Religious pluralism holds that no religion has a weighter share of (religious) truth than the others.  Pluralists maintain that many religions can capture isolated truths about reality, but none of the religions are superior in this sense.  The third view is religious exclusivism.  The exclusivist affirms what the skeptic denies: that religious theories track truth about reality.  He also affirms what the pluralist denies: that there is one objectively true religious narrative.  This doesn’t entail that all religious truths are known with certainty, but merely that we can have substantial knowledge of the truth about spiritual reality, and we can use this knowledge to judge disparate religious views.

Religious diversity poses a problem for exclusivists, and Rea and Murray undertake to show that this problem doesn’t render exclusivism unreasonable.  Putting aside pragmatic reasons for embracing pluralism, they examine how widespread religious disagreement might constitute evidence against exclusivity.  They conclude (as reliabilists) that it depends on whether or not disagreement should cast doubt on the believer’s reliability to judge the facts at hand.[1]  The mere fact of disagreement is insufficient.  Disagreement plus backgrounds beliefs (beliefs about the supernatural, morality, your own memory) work together to determine how heavily the evidence weighs.  Unfortunately, we don’t have adequate background beliefs about “a typical person’s ability to judge religious matters.”  More importantly, Christian background beliefs predict religious diversity.  So, the evidential force of religious diversity might be weakened.  Rea and Murray acknowledge that this only scratches the surface of the debate over exclusivity.

Is atheism irrational?
Alvin Plantinga has fashioned an argument which, if successful, renders atheism irrational.  Imagine that you’ve acquired evidence that your cognitive faculties are completely unreliable.  What should you make of the following proposition?

(R) Your cognitive faculties are reliable.

Well, firstly, you couldn’t have evidence for (R) that hasn’t already assumed (R), since reliable cognitive faculties are a prerequisite for assessing propositions about reliable cognitive faculties.  More importantly, if you have reason to reject (R), on the basis of the evidence you’ve acquired, then now you have a reason to doubt all of your beliefs, including the belief that (R) is true!  Defeating (R) defeats everything … resulting in global skepticism.

Why should we think that atheism gives us evidence of unreliable faculties?  According to Plantinga, evolutionary theory is concerned with survival and reproduction, and doesn’t give a fig for true beliefs.  Thus, conjoining naturalism with evolutionary theory leads us to believe that our cognitive faculties are unreliable.  Why?  The ability to arrive at truth about the world might be (and Plantinga would say is) irrelevant to the function of enabling us to survive and reproduce.  For example, consider a man who wants to die and he believes that the best way to secure death is to run away from tigers and mate frequently with women.  He’ll do just as well as the man who doesn’t want to die, and believes the best way to secure life is the same.  Thus, Plantinga argues that the probability of our faculties being reliable–given evolution and naturalism–is low.  But if so, then the atheist who accepts evolutionary theory and naturalism has a defeater for his belief that naturalism is true … and a defeater for all his other beliefs too.  Rea and Murray suggest that a more modest version of this argument might work: arguing that natural selection might produce some true beliefs, but why should we think our philosophical and religious beliefs are among these? [2]

1 There are “undercutting” and “opposing” defeaters.  It sounds like Rea and Murray are arguing that an undercutting defeater is needed, since presumably there is no opposing defeater for basic beliefs such as my belief that I was at work yesterday morning.  See this article for more information on defeaters.
2 See Plantinga’s paper “Naturalism Defeated.” Stephen Law has been working up a response.  Also, see Fitelson and Sober’s response.

March 20, 2011

Philosophical Themes from C.S. Lewis

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An excerpt from Steven Lovell’s dissertation, “Philosophical Themes from C.S. Lewis.” (pdf)

“The dissertation contains five main chapters, addressing four issues in the philosophy of religion through the writings of C.S. Lewis. Those issues are: the Euthyphro dilemma, the philosophical status of miracles, the Freudian  critique of religious belief, and an argument from Lewis that has been dubbed ‘the argument from desire’. While disagreeing with Lewis in some of the details, the dissertation defends a broadly Lewisian (and therefore broadly Christian) approach to each of these issues. Indeed, these Lewisian positions are defended with refurbished versions of Lewis’ own arguments.  In addition to a summary of some of the philosophical themes and arguments from C.S. Lewis that are not addressed in this dissertation, the work also includes two appendices. Appendix A is a short biography of C.S. Lewis. Appendix B offers a few thoughts on Lewis’ general stance on the relation between faith and reason.”

(H/T: Victor Reppert)

March 15, 2011

An Intro to the Philosophy of Religion, Ch. 3

Intro to the Philosophy of Religion Intro
After carving out the theistic concept of God, Murray and Rea turn their attention to the Christian concept of God as triune and incarnate. Can these claims be established apart from appeal to scripture?  Both sections begin with a brief discussion of the heresies before examining orthodox (officially recognized) doctrine.

“So if it turns out that Christian doctrine as interpreted by those creeds and councils is incoherent, then, at the very least, large segments of Christendom will be forced to revise their religious views and also, perhaps, to revise their views about the authority and reliability of the relevant creeds and councils.”

The Trinity
The orthodox challenge, in light of the above quotation, is to show how there are three divine persons and yet only one God.  A variety of analogies have been offered to illustrate how this might be understood. [1]

The social analogy
Social Trinitarians believe the Father, Son and Holy Spirit are one Godhead in a way analogous to Abraham, Sarah and Isaac being one family.  Each family member is not a complete family on their own; however, each member is complete in the sense of being a “complete instance of a single nature, humanity.”  Thus, the Father, Son and Holy Spirit are one in two senses: (a) they are members of the single Godhead, and (b) they each fully possess (or are a complete instance of) the divine nature.  One problem with this analogy is that a family is an impersonal set of personal beings.  “So while we can say that a family is welcoming, in fact it is literally not the family that is welcoming but rather the component members of the family.  And by the same token, it is not God that is loving but rather the token members of God.” [2]

Psychological analogies
The most prominent form of this analogy compares God with a human that has multiple personality disorder.  See Thomas V. Morris, The Logic of God Incarnate.

The statute-lump analogy
Perhaps when we say that three persons are distinct and yet the same God, we mean to say that they are same with respect to something without being identical.  Stated precisely: “x is an F, y is an F, x is a G, y is a G, x is the same F as Y, but x is not the same G as y.”  Rea and Murray ask us to consider Rodin’s statue, The Thinker.  It can be described both as a lump of bronze and as a statue.  The lump of bronze shares the same matter in common with the statue; however, we can melt down the statue and still be left with the lump of bronze.  Though they share all their matter in common, the statue and the lump of bronze have different persistence conditions, and thus are not identical.  Perhaps this helps illustrate how the Trinity is the same with respect to divine nature, and yet distinct with respect to personhood. [3]

Arguments for the Trinity
Putting aside whether or not the doctrine is coherent, are there arguments in favor of it?  Those with prior commitments to scriptural inspiration will want to examine exegetical arguments. [4]   Richard Swinburne has offered an a priori argument for the doctrine of the Trinity; here is my (rough) reconstruction:

1) A perfectly loving being exists.
2) God is essentially a perfectly loving being.
3) Perfect love requires a beloved (second person).
4) Perfect love requires a third person whom the lover and beloved can cooperate together in loving.
5) Since God was free to abstain from creating anything, it is possible that no created persons exist for him to love.
6) Therefore, there must be three uncreated persons (and anything more would be unparsimonious).

Those that deny God’s intrinsic loving nature will not be compelled by this argument.  Perhaps God would not be loving if he abstained from creating.  Others reject Swinburne’s argument, doubting that our intuitions about love should ground conclusions about God’s nature.

Incarnation
How can it be that Christians worship Jesus, when the the first commandment explicitly forbids them from worshiping anything but God?  The answer, of course, is that they believe Jesus is God incarnate.  “But what could possibly lead someone rationally to think that a thirty-something-year-old Palestinian man, born to a local carpenter and raised in a town of little import, was none other than the Lord of the Cosmos in human flesh?”

Lord-Liar-Lunatic
The Lord-Liar-Lunatic argument was developed in the seventeenth century by Blaise Pascal and then popularized in the late twentieth century by C.S. Lewis.  Pascal and Lewis proposed three competing theses about Jesus: 1) he was divine as he claimed, 2) he was an incredibly deceitful liar, or 3)  he was a lunatic.  As far as convincing those who don’t already accept the conclusion (i.e., being dialectically appropriate), the argument assumes that the Gospels are somewhat reliable–at minimum a man named Jesus existed who claimed to be divine.  In what ways has this argument been challenged?  Some propose a fourth option: that Jesus was sincerely mistake.  They point to great rulers like Julius Caesar and Akhenaton who believed themselves to be divine.  Unless one appreciates the stark contrast between monotheistic conceptions of God and other Roman or Egyptian deities, this resistance might seem plausible … but Jesus was not crucified for claiming to be a powerful superhuman, rather he was crucified by the Jewish community for claiming to be Yahweh (the omnipotent and omniscient creator of all things). [5]  After noting some other objections to this argument, Rea and Murray conclude that it appears “stronger than some contemporary critics have given it credit for being.”

Orthodoxy
The doctrine of Incarnation describes Jesus as one person with two complete natures, fully human and fully divine. A host of heresies are listed: Arianism (Jesus was not fully divine), Ebionism (Jesus was just a man), Docetism (Jesus was not fully human), Nestorianism (Jesus was not one person), Monophysitism (Jesus didn’t have two natures, only one divine nature), Appolinarianism (Jesus lacked a human soul), and Monothelitism (Jesus had only one will).  All but the last heresy were specifically condemned at the Council of Chalcedon in 451 AD.

Problems
Rea and Murray address two problems with this doctrine.  The first problem with the orthodox doctrine is that it posits a divine person with two wills (human and divine).  If Jesus the man (body/soul/will) is the second person of the Trinity incarnate, why wouldn’t there be two persons (human and divine) to accompany the two wills (human and divine)?  A second problem arises from scriptures which imply that Jesus grew in wisdom (Luke 2:52), or reported his own lack of knowledge about the last day (Matthew)–if Jesus is divine wouldn’t he be omniscient?  Likewise, how could Jesus be genuinely tempted to sin if he was divine (impeccability)?

Responses
Solving these problems requires probing exactly what it means to “have a human nature.”  Three-Part Christology says that Jesus consists of a body, soul and the Son (second person of the Trinity); notice, there is only one person mentioned since (presumably) the body and soul don’t constitute a separate person in the case of the Incarnation.  But why the special case of a body-soul not constituting a separate person?  The answer seems to be that God the Son assumed the body-soul composite, and thus human personhood is absent.  This doesn’t explain how the assuming of the composite actually works, but it does show how that the doctrine can be coherent.

Regarding the problem of Jesus and omniscience, the book of Hebrews says, “Although He existed in the form of God, did not regard equality with God a thing to be grasped, but emptied Himself, taking the form of a bond-servant, [and] being made in the likeness of men.”  Kenosis theories suppose that Jesus either abandoned omniscience or else gave the appearance of not having omniscience.   Unfortunately, this also entails that omniscience is not an essential divine attribute since Jesus is divine but not omniscient.  Another response to the problem of omniscience, developed by Thomas Morris, is the “Two Minds” view of the Incarnation in which “the divine mind of God the Son contained, but was not contained by, his earthly mind, or range of consciousness.”  The earthly conscience didn’t have fully access to the divine mind. [6]

Conclusion
A variety of problems and potential solutions confront the orthodox doctrines of the Trinity and the Incarnation.   Nevertheless, none of the objections presented succeed in rendering these doctrines incoherent.

1 See also, Jeffrey Brower and Michael Rea, “Understanding the Trinity,” Logos 8 (2005), pp. 145-57. (online draft)
2 Dr. Randal Rauser offered some helpful comments on a draft of this post.  Also see his article, “Is the Trinity a True Contradiction?
3 See Peter van Inwagen’s essay, “Three Persons in One Being: On Attempts to Show That the Doctrine of the Trinity is Self-Contradictory”, in The Trinity: East/West Dialogue, M. Y. Stewart (ed.), Boston: Kluwer, pp. 83–97.
4 James White’s The Forgotten Trinity gives excellent attention to detail regarding the Biblical basis for this doctrine.
5 Daniel Howard-Snyder, “Was Jesus Mad, Bad, or God?…or Merely Mistaken?” Faith and Philosophy 21 (2004), pp. 456-79.
6. Thomas Morris, Our Idea of God (Notre Dame, IN: University of Notre Dame Press, 1991), p. 169.

March 10, 2011

Alvin Plantinga – Science and Religion: Are they Compatible? Part 3

Alvin PlantingaWhat follows is part 3/3 of my transcription of Plantinga’s opening statement during his exchange with Daniel Dennett in 2009. The mp3 is available here. Also, Plantinga and Dennett co-authored a book shortly after this debate.

“Science and Religion: Where the Conflict Really Lies”

Speech delivered by Alvin Plantinga at the 2009 American Philosophical Association Central Division Conference.


Section 3: Naturalism versus Evolution

Naturalism comes in more than one variety.  Here, as I said, I take it to be the view that there is no such person as the God of the theistic religions or anything at all like God.  So taken, naturalism is not a religion.  Nevertheless, it is a crucial part of the naturalistic worldview which in turn plays at least one of the most important roles of a religion.  This worldview functions as a sort of myth in the technical sense of that term.  It offers a way of interpreting ourselves to ourselves; a way of understanding our origin and significance at the deep level of religion.  It tells us where we come from, what our prospects are, what our place in the universe is, whether there is life after death, and the like.  We could therefore say that it is a quasi-religion.  What I propose to argue next is that naturalism and current science are incompatible, so that there is a religion (or quasi-religion) science conflict sure enough, but it is between science and natural not science and theistic religion.  What I’ll argue is that naturalism is incompatible with evolution in the sense that one can’t rationally accept them both.  Since I’ve given this argument elsewhere I can be brief.

First, note that naturalists are all (or nearly all) materialists about human persons.  A human person is a material object through and through with no immaterial self or soul or subject.  For present purposes therefore, I’ll assimilate materialism to naturalism.  The central premises of the argument are as follows: where ‘N’ is naturalism, ‘E’ is current evolutionary theory, and ‘R’ is the proposition that our cognitive faculties are reliable.  The argument goes like this:

(1) The probability of R/N&E is low

(2) One who accept N&E concedes that 1 is true as a defeater for R

(3) This defeater can’t be itself defeated

(4) One who has a defeater for R, has a defeater for any belief he takes to be produced by her cognitive faculties including N&E itself

(5) Therefore, N&E is self-defeating and hence can’t be rationally accepted

These premises need defense, perhaps the first in particular; so, suppose there are beliefs.  This isn’t essential to the argument for (1), but it will facilitate a brief statement of it.    From the point of view of materialism, a brief will presumably be an event or structure in the nervous system—perhaps in the brain.   It will be a structure involving many neurons connected in various ways.  This structure will respond to input from other such structures: from sense organs and so on.  It may also send signals along a structure of nerves to muscles and glands thereby causing behavior.  Such a structure will have at least two kinds of properties.  On the one hand, it will have neurophysiological properties—called “NP properties”—specifying, for example: the number of neurons involved in the structure; the rate of fire in various parts of it; the change in rate of fire in one part in response to the change in rate of fire in another; the way in which it is connected with other structures, and muscles; and the like.  But if it is a belief, it will also have a property of quite a different sort: a mental property.  It will have a content.  It will be the belief that p for some proposition p.  NP properties are physical properties; having such and such a content is a mental property.  There are three ways in which, given materialism, mental and physical properties can be related.  First, non-reductive materialism: while mental properties can’t be reduced to physical properties, they supervene on them.  And take supervenience to be like this: properties of sort A supervene on properties of sort B just if necessarily, if entities x and y differ with respect to their A properties then they differ with respect to their B properties.  A necessity involved could be either broadly logical metaphysical necessity or nomological necessity—­giving us two varieties of supervenience: logical and nomological—and hence two possibilities as to the relation of mental properties to physical properties.  The third possibility for that relation is reductive materialism: according to which ever mental property is identical with some physical property.

Now, in order to avoid inter-specific chauvinism, suppose we think not about ourselves but about a population of creatures (perhaps in on of those other cosmoi proposed by inflationary scenarios) who resemble us in holding beliefs, changing beliefs, making inferences and so on.  Suppose also that naturalism holds for these creatures, and that they have come to be by the processes specified in contemporary evolutionary theory.  Now ask about P(R/N&E)—specified not to us but to them.  And consider that probability with respect to each of the three suggestions about the relation of mental and physical properties.

Consider first logical non-reductive materialism: call it ‘LNM.’  Mental properties are distinct from physical properties but supervene upon them where the necessity involved is broadly logical.  What is P(R/N&E&LNM)?  Well these creatures have evolved; we may therefore assume that their behavior is adaptive in their circumstances and that accordingly the neurophysiology producing that behavior is also adaptive.  But natural selection doesn’t give a fig about true belief just as such.  It rewards adaptive behavior and punishes maladaptive behavior, but doesn’t care about the truth of a belief.  As Patricia Churchman says, “Truth, whatever that is, definitely takes the hindmost.” [viii]

So truth in a particular belief B held by one of these creatures.  We may assume that B is adaptive and that its NP properties are adaptive.  But of course nothing so far follows about the truth of falsehood of the content that supervenes on these properties.  If the supervening content is true, excellent.  But if it is false that’s just as good.  Its falsehood in no way interferes with the adaptively of the NP properties.  We should assume therefore that the probability of that belief being true (given N&E and LNM) is about a half; but then the probability of their faculties being reliable would be low.  If you have a hundred independent beliefs and the probability of each is a half: the probability that three-fourths of them are true (which is a modest enough requirement for reliability) will be less than one out of a million.  So P(R/N&E&LNM) therefore is low.  But the same thing holds (and for the same reasons) for P(R/N&E&NMN)—where ‘NMN’ is the version of non-reductive materialism where mental properties supervene upon physical properties with nomological necessity.

That leaves reductive materialism, which we’ll call ‘RM’.  What is P(R/N&E&RM)?  Here the property of having such and such a content is identical with some physical property—­presumably a neurological property.  Again consider any particular belief B held by one of these creatures.  We may suppose that having this belief B is adaptive, and adaptive by virtue of its content as well as its other physical properties.  But once again, it doesn’t matter whether the content associated with B is true or false.  We may assume that the physical property identical with the property of having B’s content is adaptive.  The content associated with B is, of course, true or false.  If it happens to be false, this in no way compromises the adaptivity of B.  Once more then, we must suppose that the probability of that belief’s being true is about a half.  But then it would be unlikely that the cognitive faculties of these creatures are reliable.  It follows therefore that P(R/N&E) with respect to these hypothetical creatures is low.  But then of course the same goes for us: P(R/N&E) is low specified to us as well.

The next step to note is that anyone who sees that P(R/N&E) is low and also accept N&E has a defeater for R in her own case—a reason for rejecting R, for giving it up, for no longer believing it.  This defeater cannot itself be defeated.  That is because the defeater for this defeater would have to take the form of an argument; but, of course, one who accepts N&E will also have a defeater for the premises of this argument as well as for the proposition that if the premises are true so is the conclusion.  Another way to put it: any argument for R will be epistemically circular in that reliance on the argument presupposes that the conclusion of the argument is true.  But anyone who has a defeater for R has a defeater for any belief that has been produced by her cognitive faculties, including of course N&E itself.  Hence, one who accepts N&E and sees the truth of that first premise has a defeater for N&E.  N&E, therefore, is self-defeating and cannot rationally be accepted.  If so, however, there is a conflict between naturalism and evolution.  There conjunction cannot rationally be accepted.  Evolution, however, is one of the pillars of contemporary science.  Hence, there is a science/religion or perhaps science/quasi-religion conflict in the neighborhood of evolution alright.  But not between evolution and theistic religion.  The real conflict is between evolution (that pillar of contemporary science) and naturalism.  Thank you [audience applause].


viii Churchland, Patricia. “Epistemology in the Age of Neuroscience.” Journal of Philosophy. 84. (1987): 548.

March 4, 2011

Alvin Plantinga – Science and Religion: Are They Compatible? Part 2

Alvin PlantingaWhat follows is part 2/3 of my transcription of Plantinga’s opening statement during his exchange with Daniel Dennett in 2009. The mp3 is available here. Also, Plantinga and Dennett co-authored a book shortly after this debate.

“Science and Religion: Where the Conflict Really Lies”
Speech delivered by Alvin Plantinga at the 2009 American Philosophical Association Central Division Conference.


Section 2: Broader Anti-Theistic Arguments from Evolution

So Darwinism as such doesn’t include or imply the proposition that the process is unguided.  What about broader anti-theistic arguments involving evolution?  I’m aware of three sorts of arguments proposed here.  First there is the claim that evolution undercuts the argument from design, thus reducing the rational support (if any) enjoyed by theism.  Second, there is the claim that the process of evolution so wasteful and productive of suffering is not the sort of process God would use or permit.  And thirdly, there is the thought that unguided evolution as a hypothesis is superior to the hypothesis that the process of evolution has been guided or orchestrated by minds (divine or otherwise), because it is simpler and more Occamistic.  None of these objections, I believe, is promising.  While I can’t deal properly with any of them, let alone all of them in the time I have, I’ll briefly outline a response to each.

Start with the claim that evolution undercuts the argument from design, thus making it less reasonable to accept theistic belief.

According to John Dupré, “Darwinism undermines the only remotely plausible reason for believing in the existence of God.” [iv]

That is…the argument from design.  Now it’s reasonable to think that evolution makes it somewhat easier to be rational or sensible in accepting atheism.  Prior to 1859, there simply weren’t decent answers to the question: if this abundant variety of life wasn’t created by God, how did it get here?

In this connection Richard Dawkins says, “Darwin made it possible to be an intellectually fulfilled atheist.” [v]

But making it easier to be a rational atheist doesn’t as such make it harder to be a rational theist, and doesn’t as such create a religion/science conflict.  And how much support does the argument from design actually offer theistic belief anyways?  Perhaps it suggests belief in the existence of a very powerful, very knowledgeable being (or group of beings).  But that’s a long ways from theism.

In any event, however, current molecular biology may offer the materials for a different sort of argument from design, as explained in the much maligned Michael Behe’s recent book, “The Edge of Evolution.”  Michael Behe is indeed much maligned.  His argument is one of the few serious and quantitative arguments in this area.  We have the living cell, both prokaryotic and eukaryotic, with its stupefying complexity and its multitude of elaborately complex protein machines.  Behe argues that unguided natural selection is probably incapable of producing these protein machines.  His argument is quantitative and empirical rather than a priori.  Its centerpiece is the saga of the malaria parasite, Plasmodium falciparum, and its long trench warfare over the human genome.  I don’t have the space here to outline this argument, but to me as a layman the argument seems reasonably powerful though very far from conclusive.  If Behe is right, or anywhere nearly right, the probability of the existence of the cell as we find it is much greater on theism than on naturalism.  And if this is so, the argument from design is reinstated at a deeper level.  What current biological science takes away with one hand, it restores with the other.  But the real point lies in a different direction.  Belief in God is seldom accepted on the basis of the teleological argument, or indeed any argument or propositional evidence at all.  Both untutored observation and current research in the scientific study of religion suggest that a tendency to believe in God (or something very much like God) apart from any propositional evidence is part of our native cognitive endowment.  Furthermore, if theistic belief is true, it probably doesn’t require propositional evidence for its rational acceptability.  As I argued in this book, “Warranted Christian Belief,” if theistic belief is true than very likely it has both rationality and warrant in a basic way: that is, not on the basis of propositional evidence.  If theistic belief is true, then very likely there is a cognitive structure, something like John Calvin’s sensus divinitatis, an original source of warranted theistic belief.  In this way belief in God, like belief in other minds, has its own source of rationality and warrant and doesn’t depend on arguments from other sources for these estimable qualities.  The demise of the teleological argument (if indeed evolution has compromised it) is perhaps little more of a threat to rational belief in God than the demise of the argument from analogy for other minds is to rational belief in other minds.

Second, there is a suggestion made by Gould and others that the waste and suffering involved in evolution is evidence against theism.

Phillip Kitcher puts it like this, “When we envisage a human analogue presiding over a miniaturized version of the arrangement…it’s hard to equip the face with a kindly expression.”

And then it goes on to suggest, “Had a benevolent creator proposed to use evolution under natural selection as a means for attaining his purposes, we could have given him some useful advice.” [vi]

I’m not sure how such advice would be received [audience laughter], but of course we don’t require current evolutionary theory (or current science at all) to tell us that the animal world is full of predation, death, pain and suffering.  Alfred Lord Tennyson noted that “nature is red in tooth and claw” well before 1859 and no doubt some suspected it even earlier [audience laughter].  Still current science gives us reason to believe that suffering and death have afflicted the human and animal world for a much longer time that was ordinarily thought before the nineteenth century.  It has therefore given us information about the extent and duration of animal suffering … including human suffering.  The first thing to see here I think is this is a special case of the so-called “problem of evil”: a problem that is alleged to afflict theistic belief.  Sin and suffering do indeed constitute a problem or perplexity for theism, although it may be hard to specify precisely what the problem is.  Most atheist thinkers have given up the idea that the existence of sin and suffering is logically incompatible with theistic belief.  Some kind of inductive or probabilistic anti-theistic argument is presumably what’s at issue.  It has proven surprisingly difficult, however, to give a really plausible statement of a probabilistic argument from evil.  And as these arguments become more complex, they also seem to become less convincing.  Surely, however, sin and suffering create some kind of problem or at least perplexity for theists.  The existence of so much suffering and hurt in God’s world certainly seems to call out for an explanation of some sort.  And what current biological science adds to the problem is that predation, suffering, and death have been going on for a very long time.  But does this put any additional pressure on the various theistic or Christian responses to suffering and evil?  My own favorite response is the “O felix culpa” response, according to which all of the really good possible worlds involve divine incarnation and atonement (or at any rate atonement).  But then all the best possible worlds also involve a great deal of sin, and as a consequence a great deal of suffering.  Some of this suffering is on the part of non-human creatures.  Christians think of suffering, both human and non-human, as due in one way or another to sin, although not necessarily to human sin.  There are also Satan and his minions who may, as C.S. Lewis suggests, be involved in one way or another in the evolution of the non-human living world.  But learning that sin and suffering has been going on for longer than we had originally thought shouldn’t raise any additional difficulties for the “O felix culpa” response.  Suppose we learn that our world with all its problems heartaches and cruelty will endure for millions of years before the advent of the new heaven and the new earth.  That wouldn’t have much bearing, one thinks, on the viability or the satisfactoriness of this response to evil.  The new heaven and the new earth, after all, will exist for a vastly longer period than our current sad and troubled old world.  Officially at least, it will be such a long period that the length of time our current sad and troubled old world exists isn’t any proportion of it at all.  But the same goes, I should think, for our learning that our world (with all the ills there too) has gone on much longer than originally thought.  Current science shows that suffering, both human and animal, has gone on much longer than previously thought; but it doesn’t thereby diminish the value of Christian responses to the problem of evil, and in this way doesn’t exacerbate that problem much if at all.

Finally, there is the claim—perhaps made more often in the oral tradition than in print—that the hypothesis of unguided evolution is simpler and more in accord with Occamistic injunctions than the hypothesis that God or other intelligent beings have guided the course of terrestrial evolution.  Here, two points are relevant.  First, even if unguided evolution is more Occamistic than guided evolution, it isn’t at all clear that the former is—all things considered—superior as the hypothesis to the latter.  It involves fewer kinds of beings, yes, but that isn’t the only relevant consideration.  Another is their respective likelihoods, that is, the probabilities of the living world—more exactly, the variety of the living world—coming to be by way of these two hypotheses.

(1) Let ‘D’ be the proposition that the variety of the living world is come to be by Darwinian processes.

(2) ‘E’: the biological evidence

(3) ‘G’: the proposition that evolution is guided

(4) ‘U’: the proposition that it is unguided

Then our question is which is greater:  the probability of ‘D’ on ‘E’ and ‘G’, or the probability of ‘D’ on ‘E’ and ‘U’?

It is, of course, overwhelmingly difficult to make anything like reasonably precise judgments here; but perhaps we can make sensibly comparative judgments.  Consider first: P(D/E&G).  Clearly God could have created living things by way of natural selection: causing the right mutations to arise at the right time, preserving the right populations from disaster, and so on.  He could also have allowed other intelligent creatures to be involved in the whole process.  Again, it is overwhelmingly difficult to estimate the probability that this is the way in which it has in fact happened.  But P(D/E&G) is perhaps not terribly low.  What about P(D/E&U)?  Going all the way back to St. George Mivart, critics have expressed serious doubt as to whether the eye, for example, could have come to be by way of unguided natural selection operating on random genetic mutation.  Could have that is, apart from absolutely stunning improbability.    The eye, the mammalian brain, and other organs remain difficult problems for unguided evolution; but the really hard problem here for unguided Darwinism isn’t the development of macroscopic organs such as eyes and hearts.  The hard problem rather is at the microscopic molecular level: the stupefying complexity of the living cell, both prokaryotic and eukaryotic.

So for example, Bruce Alberts (President of the National Academy of Sciences when he wrote this) says, “Nearly every process in a cell is carried out by assemblies of 10 or more protein molecules…Indeed, the entire cell can be viewed as a factory that contains an elaborate network of interlocking assembly lines, each of which is composed of a set of large protein machines…” [vii]

It’s only in the last half century or so that this enormous complexity has come to view.  The eminent scientist Ernst Haeckel sums up nineteenth century opinion when he declared the cell “a simple little lump of albuminous combination of carbon.”

Of course, it’s widely assumed that in fact the cell must have come to be in that fashion.  But there is little by way of serious argument for the conclusion that its coming to be in this way is less than prohibitively improbable.  On the other hand, as I said above, Michael Behe has proposed a serious and quantitative argument for the opposite conclusion.  Given the stunning complexity of the living cell with its enormous complication, together with what we know about mutation rates, the age of the earth, population size, and the like: it seems reasonable or maybe not unreasonable to estimate that P(D/E&U) is exceedingly low.  Perhaps orders of magnitude lower than P(D/E&G).  If this is right then even if we accept ‘U’ as Occasmistically superior to ‘G’, it is inferior to ‘G’ in that the relevant likelihood is lower.

But again, the real point lies in a different direction.  The theistic noetic structure already, of course, includes the existence of God.  Relative to that noetic structure, therefore, there is no additional Occamistic cost in the hypothesis of guided evolution.  As an analogy: suppose we land a spaceship on a planet we know is inhabited by intelligent creatures.  We find something that looks exactly like a stone arrow head, complete with grooves and indentations apparently made in the process of shaping and sharpening it.  Two possibilities suggest themselves.  One: that it acquired these characteristics by way of erosion let’s say.  And the other: that it was intentionally designed and fashioned by the inhabitants.  Someone with a couple of courses in philosophy might suggest that the former hypothesis is to be preferred because it posits fewer entities than the latter.  He’d be wrong, of course.  Since we already know the planet contains intelligent creatures, there is no Occasmistic cost involved in thinking these structures designed.  The same would go for evolution.  Theists already accept divine design, and do not incur additional Occamistic cost by way of thinking of evolution as guided.  This objection to guided evolution would have more by way of teeth if we theists and atheists alike were starting from an agnostic position, and then the theists proposed to postulate the existence of a divine designer in order to explain the course of evolution.  That would be substantially like offering a theistic argument.  And then the availability of a non-theistic alternative hypothesis—providing the relevant likelihood wasn’t too overwhelmingly small—would indeed undercut the argument.  But of course, in this context the theist isn’t presenting a theistic argument.  She already accepts divine design, and hence the fact that guided evolution involves more entities than unguided evolution, is no reason in favor (with respect to her noetic structure) of the latter.  Since that is so, there is no conflict here between theistic religion and evolutionary science.

I’ve argued that contemporary scientific theories of evolution taken as including Darwinism do not entail the claim that natural selection is unguided.  But suppose I’m mistaken, or suppose instead that current evolutionary theory itself evolves in such a way that this claim becomes part of it.  This could certainly happen.  We can easily imagine the authorities in the textbooks stating the theory as such a way as to explicitly include the claim that natural selection is unguided by any personal agent.  After all, many (perhaps most) biologists believe that it is unguided.  Would that show that there is scientific evidence against theism?  Hardly.  We could imagine physics evolving in the same direction:  all the physics textbooks behind them endorsing general relativity … adding that the behavior of large-scale physical systems is never guided by any personal agents.  In either case, it wouldn’t follow that there is scientific evidence against theism.  Annexing a proposition p to one for which there is evidence doesn’t automatically confer evidence on p.  I learn that Feike is a Frisian lifeguard.  That increases the probability that he can swim.  It also increases the probability of the proposition: Feike can swim, and the next toss of this coin will land heads.  But it does not increase the probability that the next toss of this coin will land heads.  And even if, contrary to fact, there were scientific evidence for unguided evolution (and hence for atheism), that would by no means settle the issue.  Suppose there is scientific evidence against theism.  It doesn’t follow that theism is false or that theists have a defeater for their beliefs or that theistic belief is irrational or in some way problematic.  Perhaps there is also scientific evidence or otherwise for theism.

Second but more important: as I mentioned, if theism is true it is likely that it has its own intrinsic and basic source of warrant.  Something like the sensus divinitatis proposed by John Calvin or the natural but confused knowledge of God proposed by Thomas Aquinas.  If so, the warrant for theistic belief doesn’t depend on the state of current science.  Indeed, what Christians and other theists should think of current science can depend quite properly in part on theology.  For example, science has not spoken with a single voice about the question of whether the universe has a beginning.  First the idea was that it did, but then the steady state theory triumphed, then big bang cosmology achieved ascendancy, but now there are straws in the wind suggesting a reversion to the thought that the universe is without beginning.  The sensible Christian believer is not obliged to trim her sails to the current scientific breeze on this topic—­revising her belief on the topic every time science changes its mind.  If the most satisfactory theistic or Christian theology endorses the idea that the universe did indeed have a beginning (isn’t eternal let’s say), the believer has a perfect right to accept that thought.  If so, then even if there were scientific evidence against theism and no propositional evidence—­arguments, let’s say, scientific or otherwise—­in favor of it, it still might be both rational and warranted.


iv Dupre, John. John Darwin’s Legacy: What Evolution Means Today. Oxford University Press, 2003. 46.
v Dawkins, Richard. The Blind Watchmaker. W. W. Norton & Company , 1986. 6.
vi Kitcher, Phillip. “The Many-Sided Conflict Between Science and Religion.” The Blackwell Guide to Philosophy of Religion. William E. Mann. Wiley-Blackwell, 2004. 268.
vii Alberts, Bruce. “The Cell as a Collection of Protein Machines: Preparing the Next Generation of Molecular Biologists.” Cell. 92. (1998): 291.

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