Monday, 27 July 2015

Paradox of the Ravens

I came across this youtube video last night (below) which I thought was a real eye opener. The argument expressed is that we can provide evidence for the proposition all ravens are black by observing things/objects which are not black and are not a raven. So I observe a daffodil. I note it's yellow and is not a raven. This provides evidence that all ravens are black! I observe grass. I note it's green and not a raven. This also provides evidence that all ravens are black!

This of course seems preposterous. The video below explains why it seems we are obliged to accept such a counter-intuitive position:

Here is the argument as I see it and expressed as simply as I can put it:

Suppose we have 2 lists:

List A: Every single black object in the Universe.
List B: Every single non-black object in the Universe.

So together the 2 lists comprise all objects in the Universe.

If all ravens are indeed black, then it follows that every single raven in existence must belong in list A. Conversely no ravens whatsoever will be found in list B.

So if we look at every single object in list B, and none whatsoever is a raven, then this necessitates that all ravens are black.

But this also suggests that just looking at a single object in list B, and finding it is not a raven, constitutes an incredibly small amount of evidence that all ravens are black!

So is there a paradox here? I've read nothing of the various arguments expressed, but it seems to me that if we observe all objects in list B and none are a raven, then this necessarily entails all ravens are black. So the probability of each of the individual observations of the objects in list B must add up to a probability of 1. But that doesn't mean to say that each observation provides equal evidence. Thus it might be that the observation of manufactured non-black objects -- for example a green car -- does not add any evidence for the proposition. But this might be made up by other observed non-black objects which are not ravens -- for example objects which nobody has ever seen -- providing a corresponding increased degree of evidence for the proposition.

Thursday, 16 July 2015

Why Scientists and Philosophers reject the Soul

Eric T. Olson is an American philosopher who specializes in metaphysics and philosophy of mind and is most renowned for his research in the field of personal identity. He’s written one of the chapters in The Myth of an Afterlife which can be read here. I’ve read approximately a third of this book so far, but had not as of yet got to this chapter.

Similarly to the other authors of the myth of an afterlife, Eric T. Olson suggests it’s very unlikely that we have a soul which survives the death of our bodies and the reasons he gives parallels very closely the arguments given by these other authors. He says:

“ . . there is wide agreement that, possible or not, it is very unlikely to be the case (that a soul survives). All the evidence supports the opposite conclusion.

For instance, if you could remain conscious despite the total destruction of your body, you could certainly remain conscious after comparatively minor and temporary damage to your brain (van Inwagen,2002, pp. 196-198). We would expect a sharp blow to the head to affect the interaction between you (the soul) and your body, temporarily preventing your body from obeying your will and giving you sensory information, much as damage to a remote-control aircraft might prevent its owner from operating it. You would be unable to move. Everything would go black and silent and numb. The soul itself, though, would be undamaged, and ought to remain fully conscious. You would find yourself effectively disembodied, wondering what had caused the condition and how long it might last. Yet that is not what happens: a sharp blow to the head makes you completely unconscious. General anesthesia does the same thing in a gentler way. But if such a minor alteration to your brain invariably causes unconsciousness, how could you remain conscious when your brain is totally destroyed?

We also know that medium differences in the brain are correlated with dramatic differences in intelligence, alertness, mood, memory, recognitional abilities, sense of humor, and many other mental properties. As far as we know, every mental phenomenon varies according to the state of one’s brain. Though there is much we don’t know about the connections between mental phenomena and the state of the brain, there is little doubt that the connections exist. Facts like these suggest that mental goings-on are physical processes in the brain, not non-physical processes in the soul. There does not appear to be any soul—or if there is, it has nothing to do with our mental life, and its continuation after death is of no more relevance to the afterlife than the continuation of our carbon atoms.

For these and other reasons, the overwhelming majority of philosophers and scientists regard the Platonic model as a lost cause. If this were the only way of escaping the devastation of the grave, we could only hope that the experts are badly mistaken. Naturally we cannot rule this out: theories that were once supported by all known evidence have turned out to be thoroughly wrong, and theories once undermined by all available evidence are occasionally vindicated.

But it is unwise to bet against the settled scientific consensus.

First things first, and as I have mentioned before, the evidence cited here is indeed extremely compelling -- at least from a psychological perspective.  It feels to me ridiculous to suppose our consciousness survives wholly intact with the destruction of our body, yet the brain can affect consciousness so as to seemingly completely extinguish it under general anaesthesia.  But yet I nevertheless gravitate towards a belief in a “life after death”.   Why is this?  Well certainly not because I don’t recognise the compelling nature of the argument that Eric T. Olson has articulated!

In my view, in order to come to any type of provisional conclusions regarding what we should believe on any topic, we need to look at the arguments and evidence on both sides.   Thus on the one hand there’s the evidence that Eric T. Olson cites.  On the other hand, there are reasons which very powerfully suggest that it is very implausible to suppose brains create consciousness.  I explain this in my Science, the Afterlife, and the Intelligentsia

To repeat what I said there, it’s not just the case that science cannot at present explain the existence of consciousness, but rather that science, at least as currently conceived, cannot in principle explain the existence of consciousness!  Brains might cause consciousness, but if so then this causal relationship is different from any other causal relationship we see.  Moreover, we have mindless matter interacting with itself which somehow produces not just conscious experiences, but also what philosophers label as intentionality -- the power of minds to be about, to represent, or to stand for, things, properties and states of affairs.  Indeed, it seems to me that the hypothesis that brains create minds is more surprising than if someone, without any knowledge of television or television sets whatsoever, were to hypothesize that the internal components of a TV set wholly create the programmes screened. 

Furthermore if brains create consciousness it is difficult to assign a causal role for consciousness.  It seems to me incoherent to suppose consciousness is wholly causally inefficacious as I explain in my blog entry can consciousness be causally inefficacious?  Eric T. Olson takes the option of asserting that “mental goings-on are physical processes” but physical processes and “mental goings-on” are wholly characteristically different with nothing in common whatsoever.  Hence by definition they are not one and the same although one of course may cause or elicit the other.

In addition there is all the evidence, both direct and indirect, which suggests an afterlife.  Such evidence includes near-death experiences (NDEs) and the closely related phenomenon deathbed visions, evidence for reincarnation in the form of children’s recollections of previous lives (although not alleged memories retrieved through hypnosis which is much poorer quality evidence), apparitions of a certain type, and mediumship. There is also much indirect evidence which tends to suggest the continuation of consciousness after death. The most notable indirect evidence is psi phenomena. It seems to me that the totality of all the evidence suggests that it exists even if the more remarkable demonstrations of such phenomena turn out to have involved trickery. Contradicting our current western understanding of the mind-brain relationship, the existence of such phenomena suggests there is far more to the mind than is implied by regarding consciousness as merely being either a function of the brain or a causally inefficacious by-product of the brain.

And it seems we can render the concept of a soul coherent providing we conceive of a self/soul in a certain way.  The fact that mental states are affected by brain states can be squared with such a conception of the self or soul by considering the brain to be a type of "filter" (see my is a "life after death" conceivable?).
Is a "life after death" conceivable?

So why is the concept of a soul a lost cause?  We can easily see why one would conclude this if only the evidence cited by Eric T. Olson is taken into account.  Is this what all the scientists and philosophers who decisively reject an afterlife are doing? Are they just considering the evidence against an afterlife and blithely ignoring all the reasons and evidence which might suggest an afterlife? 

In all honesty it seems to me this is precisely what they are doing.  I’m approximately one third of the way through reading the myth of an afterlife, a book consisting of a collection of chapters written by different authors. With the exception of one of the authors – Keith Augustine – they have all thus far concentrated on all the various ways that the brain affects our mentality, albeit in far greater detail than EricT. Olson.  No mention whatsoever has been given by any of the authors of the conceptual difficulties facing any type of materialism -- difficulties which I regard as decisive (although I stress that just because materialism is wrong, doesn’t entail there is a “life after death”.  But it does make the prospect vastly more likely).  Furthermore, with the exception of Keith Augustine, no mention is given of the evidence suggestive of a “life after death”.

Now of course someone might point out that it is likely that they’d find the reasons and evidence for an afterlife completely lacking any merit.  Perhaps so, but they need to argue for their conclusions here.  If I am to be quite frank I don’t get the impression that they even aware of the profound difficulties that face the hypothesis that the brain creates consciousness. 

Or perhaps they consider the evidence that the brain produces consciousness to be so overwhelming that no other reasons or evidence need be addressed?  But the evidence cited by EricT. Olson doesn’t entail that the brain produces consciousness.  If changes in X inevitably initiate particular characteristic changes in Y, this does not entail that X produces Y.  They might agree with this, but insist that any change in Y (the self) means that you have not survived.   In other words the self, or soul, is held to have a certain psychological properties. If these change then you have not literally survived. But I submit this is not the commonsensical notion of the self.  If our dispositions, interests, intelligence and memories constitute the self or soul (rather than being mere properties, as I hold) then we will not have survived from our childhood to adulthood either. 

But anyway, this is all besides the point because all these points need to be thrashed out.  Ignoring them, as all the authors of the myth of an afterlife do (thus far at least), might be profitable in persuading people of the foolishness of an afterlife, but it does little in terms of trying to establish the truth.  If we are serious in trying to establish the truth or falsity of a hypothesis (whether a scientific hypothesis or not) then all pertinent information, arguments and evidence need to be considered.

Finally I would take issue with Eric T. Olson’s words in the final paragraph I quote of him.  As I’ve mentioned before consciousness cannot, even in principle, be scientifically explained -- at least as science is currently conceived.  All we have are correlations between brain and mental events.  Making any causal connections cannot in principle be provided given that we subscribe to the mechanistic concept of reality.  So what’s with his reference to the settled scientific consensus?  Presumably this refers to scientists’ opinions, but their opinions are pretty much irrelevant since, first of all, it is not a scientific issue but rather a philosophical one, and secondly, if they only consider the evidence from one perspective and completely ignore all the evidence and arguments against this position, we cannot have any confidence in their conclusions.

In addition our modern western culture is pretty much unique in emphatically rejecting an afterlife.  What do the intelligentsia know that the most intelligent people in other cultures didn’t understand?  Are modern scientists more knowledgeable on this specific issue?  Certainly there is now a far greater degree of knowledge of the correlations between brain states and specific regions of the brain, and mental states. But presumably people have always been aware that sharp blows to the head can render one unconscious, have always been aware of deep sleep, have always been aware of the effects of alcohol and other drugs.  Why didn’t this evidence convince the greatest minds in the past that we all cease to exist when we die?   My suspicion is that it is less to do with knowledge of mind/brain correlations, which has convinced the “experts” (modern day scientists and philosophers) and more to do with the birth of the mechanistic philosophy and the profound shift in the way of conceiving reality that this initiated.  Once again see my Science, the Afterlife, and the Intelligentsia.

Eric T. Olson claims modern day scientists and philosophers are experts.  Well why doesn’t he, his fellow authors of the myth of an afterlife, and other prominent figures of the intelligentsia, provide some arguments and consider the whole matter dispassionately and justify this label?

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