Wednesday, February 25, 2015

Avoiding Dependency in Global Christian Mission

Spiegel Says (my emphasis): A goatherd with his flock on a road under construction north of Nairobi Kenya. Critics say Western aid, the way it is currently structured, has made recipient countries dependent on help from abroad.

Developmental aid for Africa from the West has long been of questionable efficacy; to cut a long story short this aid has so often encouraged unhealthy dependency. See for example this article on Spiegel Online:
See also the accompanying Photo Album:

Christian Mission has faced similar problems of unintentionally promoting African dependency on handouts.. Christian Missionary and Anthropologist Dr Jim Harries lives in Kenya and has spent much time pondering and writing about these problems. He is heading up the UK April 2015 conferences advertised here. Jim promotes a method of Christian Mission that uses local languages and local resources, without the potentially destabilizing effects of Western resources. Moreover, the use of local languages challenges missionaries to gain a deep understanding of the local culture and with it comes a much greater chance of reading the subtexts that tell us about the why's and wherefore's of Western project failures in Africa.

I may be presenting a paper at one of the conferences. If I do here is the abstract: 

De-polarising the dependency vs. independency dichotomy
What is at the bottom of the frequent failure of African development and Christian mission projects, projects prompted and assisted by Western Civilisation?  What prevents Western ways seamlessly grafting on to the African context?  This paper probes both the rural African and Western cultural mind sets and discovers incommensurability between the two. This incommensurability is very apparent in contrasting views about the source of “fortune”;  that is,  the hidden engine which drives everyday events.  Differences in the understanding of the nature of this engine lead to very different perspectives:  On the one hand the rural African has little inhibition about having a resource dependent identity but the downside of this is that it can compromise proactivity and responsibility. On the other hand the Westerner who feels he comprehensively grasps the underlying mechanisms that drive the cosmos may all too readily be prey to an unhealthy control freakery and an independence of the divine. Both perspectives have positives and negatives and constitute a thesis-antithesis pair crying out for synthesis.  This current paper, which grew out of a discussion document co-authored with Jim Harries , seeks a path between irresponsible dependency and the proud self-sufficiency of independency.

As the flint of Western thought grinds against the frizzen of Africa sparks are being produced igniting the fires of many fruitful discussions about African development. These discussions in turn could help address the problematical philosophical nihilism which so easily grows out of purely secular thinking thereby plaguing Western societies with deep existential crises.

(See also:

Spiegel says: Ideally, foreign aid should not offer anything that locals cannot do themselves. Expertise can be helpful, as here in Adama, Ethiopia. But foreign aid workers should not get in the way of local initiative.

Spiegel says: Many well known stars, such as Bob Geldof, have become heavily involved in African aid. But some say that we need to get away from the idea the more money necessarily means more help.

Wednesday, February 11, 2015

Evidence: Guide Lines but not Tram Lines

For the epistemically naive evidence is thought to lead straight to the Truth.

As usual evangelical atheist Larry Moran is keeping me on the hop with his interesting and thought provoking blog. This time it's a post about "Evidence for the existence of god(s)”. I reproduce the short post in its entirety below:

Evidence for the existence of god(s)

I am always on the lookout for evidence that some sort of god actually exists. The reason I'm an atheist is because I've never seen any evidence that's the least bit convincing. I keep asking for evidence but nobody ever supplies any. Somebody suggested to Barry Arrington that there was no evidence for god(s) and that really set him off [Astonishingly Stupid Things Atheists Say].

He responded with a list of all the evidence for god(s). Here's the list. I don't find it very convincing but some of you may want to head off to the the nearest church after reading the list.

  • The fine tuning of the universe.
  • The moral sense.
  • The fact that a natural universe cannot logically have a natural cause.
  • The fact that there is something instead of nothing.
  • The overwhelming odds against the Darwinian story being true (estimated at 10^-1018 by atheist Eugen Koonin).
  • The irreducible complexity of biological systems.
  • The vast amounts of complex computer-like code stored in DNA.
  • The miracles that have been reported throughout history.
  • My subjective self-awareness.
  • The fact that we do not even have plausible speculations to account for the origin of life.

Let me say straight away that in spite of being a theist myself I would claim that the list of "evidences" supplied by Barry Arrington is flawed on several counts. I won't go into details on that score here except to say that Arrington is part of what I refer to as the Homunculus  Intelligent Design movement, and although I would agree with the general thesis that one has to introduce the concept of intelligence a priori in order to make sense of life, I reject Homunculus ID’s Intelligence vs. Naturalism dualism (See here, here  and here for example). What I want to briefly comment on here is the concept of “evidence” itself, a question that I have aired more than once on this blog.

Except perhaps in very elementary epistemic connections it is wrong to speak of evidence as a kind of deterministic rail track that inexorably and necessarily leads to the truth and where the seeker of truth is portrayed as a passive dispassionate mechanical “follower” of the evidence. In contrast the actual assessment and interpretation of evidence that gives rise to very general theoretical explanations, especially when it comes to world view synthesis, is never going to be an exact science followed by passive dispassionate agents using a strict set of epistemic rules; in fact it is probably going to remain a very passionate fuzzy science.  As I have implied before, the human mind is highly proactive and creative in the hunt for meaning and explanation: If we think in terms of the joining of the dots metaphor (where the “dots” = “evidence”) we might be getting somewhere near the truth about how evidence and theorising works in practice;  in joining the "dots" we find that the arrangements of those dots stimulates a rich set of imaginative structures that exist in our minds, structures which in turn are no doubt a function of much experience. These imaginative objects are then used in the negotiations between theory and evidence. The upshot is that we move less from evidence to explanation than we do from a priori explanatory structures to evidences; although we must acknowledge that a bad fit between explanation and evidence ought to prompt us to at least keep our proposed explanations under review. In short, evidence is less tram lines that it is guide lines.

If the imagination (and probably the emotions as well) is highly proactive in the synthesis of evidences into unified explanatory objects, it should be no surprise that Larry Moran has found that claimed “evidences for God” don’t work for him, especially as this involves world view synthesis. These higher level world view matters cannot be said to rest on hard science and so opinions will differ. Consequently, I can respect Larry’s view (re. the existence of God) that “I've never seen any evidence that's the least bit convincing”. But to express the view that the evidence for God is not convincing is not quite the same thing as saying “there is no evidence for God”.  There is plenty of evidence for God in the sense that theists assimilate many evidences into a world view backdrop that incorporates those evidences, although of course for atheists like Larry Moran this assimilation will not ring true.

Barry Arrington is part of the polarised evangelical Christian vs. evangelical atheist North American scene where opposite sides of the debate slug it out together in uncompromising terms. It’s difficult not to get sucked into this battle because the respective sides see those who are not for them as being against them. For example, the evangelical Christian culture that Arrington represents is, in my view, too close to the paranoiac anti-academia right wing Christian fundamentalists for whom disagreement with their opinions is regarded as tantamount to siding with what they perceive as the Antichrist conspiracy ranged  against them. Consequently, cordial relationships are difficult if not impossible to foster even though one might be a fellow Christian theist.

Relevant links:

Wednesday, February 04, 2015

Plenty of Fish to Fry Here

This video of atheist Stephen Fry responding to a question has impressed many; it is, after all, about that perennial problem of Christian theism, the problem of evil and suffering.  I not going to take up that difficult subject here, but instead I’m going to focus on the reaction of my favourite evangelical atheist Larry Moran. This biochemistry professor, it seems, is pretty much underwhelmed by Fry’s response and entitles his blog post “Stephen Fry blows it by assuming he knows the mind of god” and in it he writes this:

Many of my atheist friends think that Fry's response is fantastic because he really shocks the interviewer, Gay Byrne. That's naive. Most intelligent Christians have developed some very good rationalizations concerning the problem of evil. They've heard it all before and they know how to respond. One of the classic responses is that they cannot know the mind of god. But Stephen Fry knows the mind of god and this is puzzling because Fry is an atheist.

Larry Moran knows that Fry is treading very deep theological waters indeed and also knows that populist answers to theological questions, questions which have been pondered by theologians and scholars for centuries aren't going to impress those “Intelligent Christians” one little bit.  But let me read between the lines of Larry’s post, as I did when I commented on it in a Facebook entry as follows:

  ..well I suppose we can all, to a lesser or greater extent, get held up at the theodicy problem; but the crucial point is Stephen Fry is seriously thinking about theology and moreover relating it to empirical conditions! As evangelical atheist Larry Moran over on Sandwalk points out, this is a virtual defeat because it can be taken as an admission that the "God" concept has some (profound) empirical content. Evangelical atheists like Moran would much prefer to see "God" as a vacuous, obscurantist fairy tale object, devoid of all empirical meaning, rather like Russell's orbiting teapot or the tooth fairy. Moran senses that Fry, by grappling so seriously with theism, is admitting that "God", as a concept, is empirically meaningful, even if Fry himself doesn't believe God to be a reality. In Moran's eyes Fry is on a slippery slope that could conceivably lead to conversion!

In other words Larry would much prefer that Fry didn't get in bed with the theologians by effectively encouraging the debate to enter into highfalutin theological discussions about the internal consistency and/or questionable morality of the Christian creator God, as a concept. He would much prefer to simply declare the whole subject to be rationally off limits because, he believes, theology is basically non-empirical nonsense. He sees Fry playing theologians at their own game; but Larry wants to only play the game of what he thinks of as "just science". His efforts, however, are in vain; Larry’s post  attracts a very long theological looking comment thread where the character of God is thrashed out in detail. In one comment Larry throws up his hands and tells us what he thinks (My emphasis):

Theodicy is an example of the "sophisticated theology" that Christians claim we atheists are ignoring. It's what PZ Myers was mocking in the Courtier's Reply. We atheists have already lost the battle once we start debating the merits of theodicy because we concede the possibility that god exists and now we are just quibbling about his properties.

Larry wants to just sweep all that theological sophistry off the table without engaging its finer points; after all, to him it’s just so must time wasting casuistry. Trouble is, if Larry is to seriously criticize Christianity (as is Fry) he can’t avoid thinking theologically and I have caught him at it several times:  See for example here and here

PZ Myers thinks Fry's response is good but, however, a “fairly standard atheist answer”. What does interest me is the following comment by Myers:

Another factor, to me, is that if their afterlife were true, they expect us to stand before a deity as a supplicant, with a vast power differential, and then essentially grovel. There is no human dignity and no hope in their vision of death — your choice is to submit or suffer. If this god could see into our minds what we were truly thinking, then there is also no point to pretending, and it would know it: this would be a monstrous alien passing judgment on a humanity it regards as corrupt, debased, and wicked, and the only propitiation it could get from us is our terror…… Fortunately, there is no evidence and no reason to think we will continue to exist beyond the death of our bodies, or that there is such a cosmic tyrant, so I’m relieved that I don’t have to worry about a Christian afterlife.

The answer to this response is very much bound up with the personality of God; The vision Myers portrays here is of a God who is a very repugnant personality, someone who, if he existed, Myers wouldn't want anything to do with (and neither would I!). Myers is very much consoled, therefore, by his belief that this God doesn't exist. Western fundamentalism is unlikely to disabuse Myers of such an opinion because the fundamentalist God is the God of hell and hamnation (See also here, here and here for example). If God does exist then Myers really needs to meet him personally as does Larry Moran. In fact in his blog post this is what Larry would say if he met God after he had died….

My questions would be "Who are you? Which groups of humans (if any) got it right when making up a religion? Tell me about yourself and why you didn't reveal yourself to me."

Good question! Which group of exclusivist scriptural literalists have “made up” the right religion?One can find a different species of fundamentalism creeping out from under every stone one turns. I am inclined to answer this question with Hebrews 1 and Philippians 2 but there is no shortage of fundamentalist brands out there claiming that the gospel of Hebrews 1 and Philippians 2 only fully applies to those affiliated to their observant communities of strict practice and belief. So, I for one can’t be too hard on the opinions of Larry Moran, PZ Myers, or Stephen Fry for that matter.

Saturday, January 31, 2015

Dodgy Flaky Logic

The above, which I recently found on the web, is part of a formalisation of the ontological argument. With a few axioms and logical deductions there you have it, the holy grail of faith, a proof of God's reality! Print it out, laminate it and you'll have a pocket sized theorem for God's existence ready to pull out and read through when your faith is feeling a bit rocky or if you want to convert an atheist on the spot. 

But seriously don't bother; this formalisation is not exactly robust, in fact it is extremely flaky. The theological motivation for the argument is not in doubt: i.e. a desire to show that somehow God is a necessary being, a being with aseity - this is a highly plausible proposition for theists like myself who feel that the concept of absolute nothingness and in particular the non-existence God are probably contradictions (although we don't have proofs, of course). But the above is unlikely to be part of a sound demonstration of God's aseity. Basically this type of argument depends on sheer existence being regarded .... no make that "defined", as a "positive property". It then follows that God, as the greatest being one can conceive, must an have existence; this follows because God would fall short of being the greatest conceivable being if he lacked the "positive" property of existence.

One could no doubt write a book on ontological arguments of the above character, arguments which no doubt draw on Anselm's ontological argument of the 11th century. Below. however. are some remarks (R1 through R4) followed by conclusions and corollaries (C1, C2, Cor. 1 and Cor. 2) indicating where I would take my critical analysis:

R1:  The truth of the above line of argumentation is a logical trivialism that depends on definitions: Clearly if one is going to define "existence" as a positive property and then define God as the being with all possible positive properties it trivially follows from these definitions that necessarily God exists..... one is effectively simply defining God as an existing being. For if a being doesn't exist then that being can't be God, because God, by definition, must have the property of existence!

R2:  Axiom A2 is not axiomatic; consider for example the optimisation problem where two desired "positive" properties complete against one another:  For example, in aircraft design radar stealth can compromise performance positives.

R3:  A5 looks more like a subjective definition than an axiom. One man's positives may be another man's excrement. For example, radar stealth is positive for an attacker but not for the attacked.

R4: I'm unhappy with the treatment of extrinsic and intrinsic properties.  (See D2 above). Presumably various platonic mathematical objects stand in relationship to God in someway and therefore become extrinsic properties of God. Some of these platonic objects may be far from what we would subjectively evaluate as "positive". It follows, therefore, that God has non-positive extrinsic properties that imply God's properties. So, are these non-positive properties considered to be "essences" of God?

C1: What a mess!

C2: Better go back to the drawing board!

Corollary 1: I don't think I'll bother.

Corollary 2: Take a day off instead

Saturday, January 24, 2015

Chaoskampf, Cancer and Conspiracy

The Cancerous Chaos Beast: the mythology of the mundane and banal

For the second time in as many weeks we find evangelical atheist Larry Moran "warming" his heart in a perverse nihilistic sort of way with news that  randomness once again has a big influence in the affairs of this world; the first time it was random drift as one of the important engines driving evolution, this time its about 50% of cancers being caused by nothing in particular but a bit of bad luck. All this is very much in line with Larry's vision of an acausal world largely driven by meaningless forces, empty of purpose.  Funny part about it is that I'll have admit he may well be right about this; from spontaneous corruption of genetic information in cells to stray cosmic rays and background radio activity, such influences are unlikely to be traceable to any deeper causes. I also think he may be onto something when he says that this is a message that many people do not want to hear; the implication is that there is human resistance to accepting that meaningless, goalless forces can play a large and decisive role in life. Moran quotes David Gorski, a quote I reproduce below with my emphases in bold:

It’s understandable that humans crave explanation, particularly when it comes to causes of a group of diseases as frightening, deadly, and devastating as cancer. In fact, both PZ Myers and David Colquhoun have expressed puzzlement over why there is so much resistance is to the concept that random chance plays a major role in cancer development, with Colquhoun going so far as to liken it to ” the attitude of creationists to evolution.” Their puzzlement most likely derives from the fact that they are not clinicians and don’t have to deal with patients, particularly given that, presumably, they do have a pretty good idea why creationists object to attributing evolution to random chance acted on by natural selection and other forces.

Clinicians could easily have predicted that a finding consistent with the conclusion that, as a whole, probably significantly less than half of human cancers are due to environmental causes that can be altered in order to prevent them would not be a popular message. Human beings don’t want to hear that cancer is an unfortunately unavoidable consequence of being made of cells that replicate their DNA imperfectly over the course of our entire lives. There’s an inherent hostility to any results that conclude anything other than that we can prevent most, if not all, cancers if only we understood enough about cancer and tried hard enough. Worse, in the alternative medicine world there’s a concept that we can basically prevent or cure anything through various means (particularly cancer), most recently through the manipulation of epigenetics. Unfortunately, although risk can be reduced for many cancers in which environmental influences can increase the error rate in DNA replication significantly, the risk of cancer can never be completely eliminated. Fortunately, we have actually been making progress against cancer, with cancer death rates having fallen 22% since 1991, due to combined efforts involving smoking cessation (prevention), better detection, and better treatment. Better understanding the contribution of stochastic processes and stem cell bio
logy to carcinogenesis could potentially help us do even better.

So why does this pique my interest? It's because it has tell-tale similarities with the human tendency toward paranoia and conspiracy theorism; conspiracy theorism is the imaginative multiplying of the machinations of sentient entities behind the scenes thought to be engaged in deception and/or acts against us. The motive for conspiracy theorism seems in part down to an unwillingness to accept that mundane and banal factors often have a big role in fortune; we may be tempted to feel that that fortune is worthy of grander narratives to explain it, narratives whose star turns are evil Machiavellian agents. This can have the effect of dignifying and mythologizing human struggles against the chaotic and the random. Personification of human woes can be cathartic because it provides a sentient target that anger can be directed toward. Cancer, with all the difficulties in its successful treatment, is prime material for conspiracy theorism. And yet this is in spite of the fact that in Western Christian tradition, the concept of Satan has a close association with  idea of the chaoslkampf, the beast who emerges from the abyss of chaos, the seething cauldron of randomness.  Not really very heart warming stuff I would have thought!

Wednesday, January 21, 2015

Misplaced Concreteness: The Theology of the Homunculus.

Is there an homunculus behind the scenes driving evolution?

Astronomer Otto Struve (1897 – 1963) is quoted as saying this:

An intrinsically improbable event may become highly probable if the number of events is very great….It is probable that a good many of the billions of planets in the Milky Way support intelligent life. To me this conclusion is of great philosophical interest. I believe that science has reached the point where it is necessary to take into account the action of intelligent beings, in addition to the classical laws of physics.

This statement is of IDlogical interest on several counts.

ONE: As Struve tells us sufficient trial resources (in terms of planet numbers in this case) can turn the improbable into the probable. But Struve is thinking in mere billions; this in itself is far from sufficient. For life to be generated with a realistic probability we must select one or both of two mathematical conditions: 1) An a priori physical regime which constrains the physical possibilities to such an extent that trial resources quantified with a mere 3 digit logarithm are capable of reaching life, and/or 2) A physical regime which is capable of returning trials whose number can only be quantified with a very large logarithm. *1

TWO: Interesting to note that Struve sets up an intelligence vs. physical law dichotomy –  at first sight this looks very much like the kind of thinking behind the explanatory filter epistemic of the de-facto Intelligent Design movement. But unlike the North American ID community I doubt very much that Struve was arguing from a subliminally theological position. More likely he was arguing from the point of view that “Law&Disorder” physics is a primary causal agent, whereas intelligent life is a secondary causal agent derived from physics; i.e. life is a product of the cosmic physical regime. I suspect that Struve is following the mainstream academic view that separating out physical action and intelligent action in to different categories is not a fundamental category division but one of utility: Deriving life from physical first principals is analytically difficult (if not impossible) making necessary an artificial discipline division where a higher level phenomenon like life is dealt with more descriptively by biologists.  In a similar way geologists who deal with complex geological processes don’t always work back to the first principles of physics, but cut the knot by talking about a separate category of “geological forces”; that’s not to say, of course, that geologists believe “geological forces” have any vitalistic basis. Likewise, most biologists are likely to believe that the kind of intelligence Struve is talking of would trace back to the generating power of basic physical processes. Needless to say atheists would favour this philosophy, a philosophy which doesn’t take intelligent agents as a given with all the potential there of smuggling in the divine. Of course, the de-facto IDists believe exactly the opposite; for them intelligence (subliminally, divine intelligence) must be taken as a given when reckoning up creative processes.

THREE: In the foregoing we’ve seen how intelligent action is put into a different category to “natural forces”, although for atheists this is done for utilitarian rather than fundamental reasons. It is surely ironic that this manoeuvre readily leads on to the Intelligent Design community’s explanatory filter epistemic. In this epistemic intelligent action is effectively placed on the same logical level as Law&Disorder explanations. In fact in most everyday contexts the explanatory filter of the IDists is robust; after all, something like this epistemic is used by archaeologists when they are trying to decide whether an object is an artifact or of natural origins. In short the explanatory filter is exactly the method one uses when one is faced with the possibility of action by either humans or aliens; but what about for God?

FOUR: That the de-facto ID community use the explanatory filter, a filter comfortably used by archaeologists and implicit in Struve’s statement above, says a lot about de facto ID theology.  This theology is a dualist theology where God has become an homunculus-of-the-gaps default agent of causation who acts almost within the cosmos and is invoked as an explanation when “in principle” physical explanations are difficult if not impossible to find. As I’ve complained many times before on this blog, this theology has the effect of setting up two mutually exclusive categories of causation, namely the physical and the divine. We know of course that what the de-facto ID community obliquely refers to as an “Intelligent Designer” is, behind closed doors, identified with God rather than aliens. God thereby becomes  a distinct “cause” to be lined up in an identity parade of all the other possible agents of “causation” that work within the cosmos. This has the pernicious effect of placing God very much inside creation like some super-alien, violating at a stroke both His eminence and immanence.

Moreover to talk of God being a “cause” also does an injustice to God. The notion of “causation” is itself very much a concept derived within the context of the contingent patterns of behaviour displayed by the physical universe; causation, in fact, can become difficult to define or even undefinable in connections where we are dealing with timeless patterns and/or disorderly patterns. Admittedly when talking about God it is almost impossible to do so without using metaphors based on our experience of this world, but some metaphors are not as good as others and to rank God as an agent of causation in a very literal sense is particularly insidious; the fallacy of the Kalam argument is a sign of this.

 FIVE: For myself I prefer the metaphor of the cosmos as a giant thought pattern or story created in the mind of God; it’s as if an author like Tolkien created and maintained his world of Middle Earth in his mind rather than reifying it in physical print. This metaphor satisfies to some extent the theological demand that God is both eminent and immanent in relation to the very contingent patterns of our world. We are effectively immersed in God rather than God being a homunculus who is immersed in creation as an ancillary agent of causation, occasionally turning up to do something special. The immersed human perspective on the physical workings of our world is a bit like the perspective of someone zooming in with a powerful microscope and looking at the behaviour  of individual neurons of the human mind and then wondering where the intelligence is; one only finds that intelligence at the high system level, in the big picture.

Above all, this metaphor satisfies the theological requirement for the otherness of God: The patterns of our world are contingent with no logical necessity and therefore very much other than the presumed aseity of a God who hosts them. These contingent patterns have been dragged out of platonic space and reified in an act of creative divine thought. In the sense that these patterns have a kind of immaterial platonic existence prior to reification, gives them a platonic existential status that is independent of God's existence; i.e. they are other than God. So, just as Tolkien's Middle Earth is other than Tolkien, the cosmos is other than God. God and Tolkien create in as much as they reify pre-existing platonic patterns.

It is tempting to think of the distinction between God and creation as bound up with a distinction of “substance”. But identity of “substance” is a derived concept based on our experience of the macroscopic physical world where material object integrity is only maintained by clear spatial separations and demarcations. This concept of substance breaks down, however, in the microscopic world of identical particles where it becomes clear that distinction of substance can only be maintained by clear distinction in patterns of behaviour, patterns determined by such properties as charge and mass.*2 That is, “substance” is bound up with the extrinsic properties bestowed by patterning and is not an intrinsic property.

*1.  What do you do if the universe only has a very limited number of particles, say 10^80 and therefore has very limited “trial resource” capability? Simple; you use quantum mechanics, a method whereby the possibilities open to a collection of particles are all explored at once. Individual particles are then effectively “smeared” over large volumes.

*2. Identity of “substance” is a problematical concept in the context of sheer patterning. Consider for example a binary pattern where we have two separate digits both set to “1”. Our use of common language, a language used to dealing with distinct concrete objects, tempts us to talk of these binary digits as distinct entitles, as if they had their own separate "substance"; but if this were true it would be possible to swap the digits and then claim that each separate digit has been moved. But as per quantum statistics no change has actually taken place and the "swap" doesn't count as a distinct combinatorial item. Ergo, talking about “swapping digit positions” is only a figure of speech and is otherwise meaningless.

Relevant Links:

Saturday, January 17, 2015

The Road to Somewhere

Random drift/walk, backwards or forwards. As long as you don't come off the rails you'll end up somewhere.

There has been a little flurry on the internet about the question of the Zebra's stripes: What function do they serve and how did they arise?   Evangelical atheist Larry Moran offers a possible alternative to the adaptive explanation: 

There's a fifth possibility: maybe there's no reason at all and stripes are just an evolutionary accident.....The point is that the prominence of stripes on zebras may be due to a relatively minor mutation and may be nonadaptive. That's a view that should at least be considered even if you don't think it's correct. 

This answer no doubt fits in very well with Larry's philosophical position as does his interest in "random drift" as one of the mechanisms of evolution; he might be right, after all he's the expert. But he seems to have little cognizance of the actual role of randomness in the greater scheme of things: For standard evolution to have the slightest chance of getting results the "random diffusion" of evolution must be working within a very constrained space indeed. Yes, evolution may go "backwards" and "forwards" at random, but for that to happen the current theory requires  "rails" or "constraints", in terms of the fitness space*, to be a given.  This is something that Larry just hasn't wrapped his head round. Am I being stupid in wondering why?

Relevant Links: 

* If the fitness space is an "information" given then it follows that the problem of finding life has effectively been solved before the computation of evolution has started; This view is not a horse I'm backing. See

The  General Theory of Evolution: But it only works if you've got rails