Sunday 31 January 2016

Three Wise Men - A Parable

Once upon a time, three wise men were walking along the top of a long, high cliff.  Being men, they didn't talk much but rather spent their days belching and scratching various parts of their anatomies.  One day, however, the least cynical and skeptical of them – Trevor – cried out, pointed out over the ocean and said "I saw something, a vision of a distant land, a wonderful land, one in which we could experience eternal bliss, if only we could reach it!"

They stopped and they stared in that direction, but try as they might, none of them saw any distant land although Trevor did point at the occasional cloud, saying his paradise looked a bit like that but much, much better.

"Hm," said one of the other two wise men, Anthony, "It seems to me that you might be mistaken about what you saw, Trevor, but it is indeed possible that there is something of interest in that direction.  The key question is how best to reach it.

"We are three men, wise in our ways, but totally impractical and weak of body, so we can neither build a boat nor swim to any possible distant shore.  We know that we stand upon this cliff, that waves crash upon the rock below, that across the waters there may or may not be another land, fair and wonderful as our friend here claims.  What say you?"

The third wise man, Denis, spoke.  "I did not personally see this land that Trevor saw, but I am convinced that it exists.  Why should he claim to see that which he did not?  And has it ever happened that a man was misled by his perceptions?  Do we not always see clearly and true?  I choose to retrace our path, to reject our progress so far and to seek out a way across the waters in our distant past."

Then Trevor spoke.  "No, that is not the way, I shall build a bridge here, right here.  We are all here and that can be no coincidence.  It must assuredly be that the path to the distant land can be built from here, using only the materials available to us now and with no more than the wisdom we have gleaned in our travels."

Trevor quickly collected some rocks, piled them upon one another and declared that his bridge was now all but complete.  "See, my friends, this bridge is clear evidence that the distant, wonderful land exists exactly as I described."

"Hm," said Anthony, "I find your poorly constructed bridge to be totally unconvincing, Trevor.  And Denis, I doubt that we passed a way across the ocean in our past wandering and yet failed to notice it.  Perhaps it is true that we overlooked such a thing, but if so, this is merely evidence that we are apt to be misled by our perceptions and that Trevor might well be wrong about what he claims to have seen.

"No, my friends.  I feel quite sure that there may be something of at least prosaic interest across this ocean of ignorance before us, some truth to be revealed and furthermore I am sure that, if we have glimpsed any aspect of that truth, it is only because we have come so far.  I shall continue forward, seeking a land bridge – a natural bridge – in order to understand the reality of what lies beyond this ocean, be it the wondrous land of Trevor's febrile imagination or something far more mundane yet infinitely more wonderful, by stint of being true."

And so, after centuries of struggle, Anthony broke free from the attempts of Trevor and Denis to either subdue or slay him for his lack of faith in the distant, wondrous land and he continued along the cliff.  Occasionally he would turn, belch, scratch himself and glimpse some new aspect of what lay beyond ocean.  Sometimes, the path along the cliff would bring him closer to resolving the mystery and, at other times, any perceived proximity was entirely illusory.  But he was slowly making progress.


In the meantime, Trevor sat on his bridge and Denis retreated steadily into the past.  Both looked out across the ocean from time to time.  And belched.  And scratched.  Because, despite their wildly different paths, they too were men.

Thursday 28 January 2016

Galilean to Special in One Page

This is not the first time that I have tried to explain how to get from very basic (Galilean) relativity (the si = so + vt sort of thing) to special relativity.  What I have done here, however, is try to boil it down to one page that could conceivably be printed out and pored over.  Here goes:


So, what I am wondering is – does this make any sense to anyone other than me?

I should, perhaps, explain some things.

First, priming notation in the uppermost box.  The prime indicates that the quantities in question are not fixed, the distance (x') between M and the little cloud (notionally an explosion at some location) changes with time (t').

This notation is carried through to the second box.  In this box, however, it's not necessarily the case that we know the location of the explosion.  Without external assistance, we can't immediately know where it happened without knowing when it happened, and we can't immediately know when it happened without knowing where it happened.  Therefore, rather than consider the explosion per se, we consider the photons from the explosion at the moment that S and M were collocated.

In the third box, it becomes clear that prime notation is relative.  For S, primed means "in motion relative to me" but for M, primed means "stationary relative to me".  Another way to think of it is that x' is always the distance between M and the event and t' is always the time taken for a photon to reach M from the event, while x and t relate to similar values associated with S, irrespective of which is moving (S or M).

Finally, in the lowermost box, I mention "inequalities".  I think that this is pretty obvious, but the point is that if S is in motion away from location at which S and M met, then it will take more time for those photons to reach S than it would if S were stationary.  In each case the other's measure of an invariant distance is one's own measure multiplied by some factor (which we go on to calculate).

The remainder is, I believe, pretty self-explanatory.

A further step one can take is to simply divide the resultant equation by c.  This gives us:

x'/c = (x/c - vt/c)/√(1 - v2/c2)

And, since x = ct and x' = ct'

t' = (t - v/c2.x)/√(1 - v2/c2)

This is the standard Lorentz Transformation in the time domain.

It's all quite simple really.

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It might be worth noting that, in the process above, I make no assumptions or claims about the value or nature of c.  We do know that light from an explosion consists of photons that travel at some speed.  We could even consider one photon that passes M and continues on to S rather than two separate photons.  There's nothing in the scenario which would drive a change in speed of the photon.  We don't need to know more than this to arrive at our equations and the odd features of relativity (like photons always travelling in vacuo at c compared to individual observers irrespective of any motion they might have relative to other observers and having two spaceships travel towards the other at 0.75c each [relative to a third observer] but at 0.96c combined [relative to each other, rather than 1.5c]) fall out of those equations.  The value of c becomes (in this derivation) merely something that needs to be measured.


Interestingly, it was Galileo of Galilean relativity fame who is credited with first attempting to measure the speed of light in 1638.  He concluded that it was very fast, if not instantaneous and gave it a figure of at least 10 times the speed of sound (so therefore at least 3403 m/s).  Given that he had concluded that light has a speed, Galileo could have conceivably arrived at special relativity with no more than the information that he had to hand.  To be fair to him, when he attempted to measure the speed of light Galileo has been under house arrest for five years, having been found guilty of heresy for his support of Copernicus, and he died four years later.  And even if he had arrived at special relativity, such an idea may have been considered too heretical for him to pursue with the church looking over his shoulder. 

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I thought it might also be worth mentioning the last step, in which I drop the subscripts.  I only do this to arrive at the standard equations.  I would keep the subscripts, if that were permitted, because I think they make some things clearer.  For example, it might not be immediately obvious by (4) and (5) are actually the equations for length contraction.

Consider xS and xM. The former, xS is a measurement made by S who is considered by M to be in motion.  What is xS in terms of xM?  This is given by (4), xM = γ.xS so xS = xM/γ.  Using standard length contraction terms, this is L = L0/γ (occasionally and, rather confusingly, written as Δx' = Δx/γ – although this usage appears to have declined over the past decade or so).

Wednesday 20 January 2016

Gyroscopes on Earth

I posed a question in the article Gyroscopes on the Moon, at r/AskPhysics and also in a dedicated r/Physics question thread but, as of the time of writing, I've not had a response.

Given how swift people have been to pile on when there is a vague hint that I might be wrong, I thought I might provide what I think might be the answer, put my neck on the line.  Perhaps that might elicit a more authoritative response.

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My thinking is this.  The Earth is orbiting the Sun and the path the orbit describes is a geodesic.  Effectively, therefore, the Earth is travelling along a "straight line" in curved space, rotating as it does so.

This rotation is where it gets a little complicated.  Imagine that we had a non-rotating body which has a uniform linear motion with respect to either the galaxy or the cosmic microwave background (CMB), moving in flat space.  Aim it at a large enough star so that it's just right for entering into a stable orbit.  What this non-rotating body is doing is following a "straight line" in the space that is curved around the star.  If I've thought it through properly, in this simple two body system there is no reason why the non-rotating body should start rotating.  However, the curvature of space will be such that, once in stable orbit, the body will show the same face to the star at all times – it will, in effect, be tidally locked.  To an observer of the system, it will appear as if the body has a rotational period equal to its orbital period – but, in another sense, it's not rotating at all.  It makes sense that orbiting bodies tend towards being tidally locked because this is a minimum energy state, the relativistic equivalent of being stationary.

A gyroscope on a non-rotating body with uniform linear motion does not undergo precession.  This should not change once the body is captured in an orbit – being in a stable orbit will put it in free fall, so not even the gravity of the star will be a factor.

So, how can we relate this situation to the Earth?

The Earth is certainly in a stable(-ish) orbit around the Sun, so the orbit itself should not have any effect on gyroscopes on Earth.

However, the Earth is not tidally locked, and it therefore rotates rather than being non-rotating, so gyroscopes on Earth will be affected by that rotation.  However, a gyroscope on the Moon, which is a tidally locked body, should not be affected by the Moon's apparent rotation.  (Note that this is merely a conclusion I've come to, not a statement of fact.  There may be errors in my thinking, something that I've overlooked so that lunar gyrocompasses would actually work.  I've not been able to see any indication that this has been tested.  The lunar rover had a "navigational gyroscope orientated in relation to the Sun") rather than a gyrocompass per se.  There doesn't appear to be any intention on relying on gyrocompasses in plans for the next lunar mission either.)

There are a couple of apparent flies in my ointment.  The first is that the Earth is on a tilt with respect to its orbit of the Sun (from the ecliptic), and this tilt does not appear to change during that orbit.  At perihelion, when the Earth is closest to the Sun, in early January, the North Hemisphere is tilted away from the Sun but at aphelion, when the Earth is furthest from the Sun, in July, the Northern Hemisphere is tilted towards the sun.

If we conceptually smoothed out space, so that the Earth was following a straight path, this would mean that its axis of rotation would be moving in an annual cycle (and we've just removed that cycle by turning the orbit into a conceptual straight path).  I did consider, momentarily, that it could have something to do with the fact that the Earth's orbit is elliptical and the direction and extent of the tilt is related to the eccentricity of the orbit.  This is highly unlikely though because the tilt is 23.5° from the ecliptic while the eccentricity of our orbit is minuscule at about 0.0167, making it pretty much circular even though even this tiny eccentricity does have a minor effect on our seasons (warmer summers in the south, which is counteracted by the greater proportion of ocean to landmass in the Southern Hemisphere which actually makes it cooler overall than the Northern Hemisphere).  It's more likely, I thought, that there's another factor at play.

The other apparent fly in the ointment is that the Earth itself precesses.  There's a 26,000 year cycle in which the tilt of the Earth changes, such that while Polaris is currently the (north) Pole Star, that won't be the case in a few thousand years.  Vega will apparently take on the role in about 13,000 years.  This precession manifests because the Earth itself is acting like a gyroscope and some force is making its axis of rotation tend to point towards the north ecliptic pole (also see this graphic).    Note that this means that, on average, over a period of 26,000 years, the axis of the Earth's rotation aligns with the axis of the Earth's orbit of the Sun (axis of the ecliptic).

If the Earth itself is being precessed by its orbit around the sun, with a period of 26,000 years, then a gyroscope should also be precessed by the same phenomenon, but probably only very weakly.  I'm not quite sure what the problem is with my geodesic thinking, but it seems to be wrong and therefore, I would have to presume that gyrocompasses would work on the Moon.  (It'd still be interesting to see the results of an experiment though.)

As to whether there would be a wobble or an offset, I think that (for a gyroscope on Earth submerged in a viscous fluid so as to act as a gyrocompass) there would be a very tiny offset from the north celestial pole towards the north ecliptic pole and this offset would change over a period of 26,000 years – so yes, I think there would also be a wobble, in that offset, or perhaps more of a circle, but either would be pretty hard to detect over such short periods as a human lifetime.

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Of course, I might be wrong, I might just be telling myself a complicated story using concepts that don't cohere as well as they might first appear to, but please don't let my free admission stop you from attacking the ideas above if you think they are misled.

Monday 18 January 2016

Pimping the Well

The recent comments by Scott Church and Anonymous on "poisoning the well" may reveal an interesting strategy on their part, one that I call "pimping the well".

Their argument is that some people, such as myself, employ a strategy in which the intentions of their opponents are maligned rather than addressing their arguments.  An inherent assumption here is that such efforts will work (or would work if there wasn't a shrill chorus of "poisoning the well" accusations).  This might be the case if the arguments did not stand by themselves and they absolutely needed some authority on the part of the person making the argument.

Scott Church was quick to point out the credentials of Luke Barnes and even went so far as to say that Barnes' "home page (linked from this blog) lists his CV, his research, his popular and refereed publications … everything one needs to vet his claims".  This, I think, is a clear case of "pimping the well".  Look how well (ha ha) credentialed this person is, his arguments must therefore be true.

That's not how it works.  Barnes' arguments would be correct if they are correct, even if he were a complete nobody with no history.   And they'll be incorrect, if they are incorrect, despite having ticked all the boxes.

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While I am at it, I would like to point out another little peculiarity.  Scott first, but then Anonymous, wanted to paint me as guilty of poisoning the well.  Anonymous even wants me to "to withdraw the objections rather than keep defending the indefensible".

It seems to have escaped their notice that, at least in recent times, I have posted two different comments on Barnes' blog: one addressing his paper with Geraint Lewis (reproduced with links intact here) and another addressing his diproton disaster.  These are quite different comments.

The former, which I wrote first but which appeared on his blog later, attacks his stance as a cloaked theist in general and his association with the Templeton Foundation specifically.  I made absolutely no comment on the content of the document that he was referring to, the paper co-authored with Geraint Lewis.  I have no idea what arguments they have deployed, so how could I?

In the latter, I made comments about the arguments in his diproton disaster paper, but I made no comment whatsoever about his theism.

The accusation of "poisoning the well" only stands if you read these comments together and ignore the fact that they are completely different comments addressing different issues, written at different times.  Effectively, what these people (Scott Church and his anonymous admirer) are implying is that since I have questioned Barnes' impartiality in a comment (and a number of my own blog posts), then any comments I make about his arguments, no matter how hygienically (ie without making any attempt to poison the well in my comments on his arguments by acknowledging his theism, be it cloaked or otherwise), then I have fallaciously poisoned my own well, making my objections invalid.  In other words, they are saying it's a fallacy when they (erroneously) claim that I have committed it, but it's not a fallacy when they imply that I am the victim of it (apparently as an "own goal").

One has to admire the chutzpah of these people.  I'd be ashamed to be involved in such duplicity, but they have an extraordinary level of self-confidence and self-righteousness that the rest of us can only aspire to.  And their efforts to be cast in the role of victim are worthy of an Oscar.

Sunday 17 January 2016

Gyroscopes on the Moon

This is another one of my off-the-wall questions, one for which I don't have any definitive answer but, given my track record, may still get me into trouble with some expert or another.  That said though, while I have vague inkling as to where the answer might lie, I don't pretend to know it’s precise nature.  And I may be completely wrong as to where the answer lies as well.

Gyrocompasses use gyroscopic precession to identify true north.  Basically as the earth rotates around its axis, gyroscopic torque is induced on a gyroscope that is somehow limited in its motion, precessing it such that it points to true north, or to the north celestial pole.  If weights are used to force the gyroscope to point to the centre of the Earth in one axis, the gyroscope's other two axes will end up parallel with the Earth's surface and it will point true north.  If a viscous fluid (or equivalent) is used, the relevant axis of the gyroscope will become parallel with the Earth's axis of rotation, pointing north.  The viscous fluid is used, as far as I can tell, to dampen overshoot and allow the gyroscope to settle on north rather than dithering on either side of it.

Now, this precession is due to the rotation not so much of the Earth around its axis as the rotation of the gyroscope around the Earth's axis of rotation.  In effect, if not in actuality, it is the centripetal force on the gyroscope that leads to the precession.  However, the gyroscope in question is not only rotating around the Earth's axis of rotation, it is also rotating around the Earth's axes of orbit (of the centre of mass of the Earth and the Moon and the centre of mass of the Earth and the Sun).  There's also the orbit around the centre of the galaxy, but this is a pretty slow orbit, so I think we can disregard it.

My question is this: would a highly precise, dampened gyroscope still have a detectable (even if extremely minor) wobble related to the combination of the Earth's orbit(s) and the Earth's rotation – or would it stay fixed on a celestial north pole defined only by the Earth's rotation?  If there is no wobble, why isn't there one?  In other words, why is the rotation around the Sun not a factor (if it isn't)?

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The title, by the way, is related to apparent fact that a gyroscope on the Moon might be forced to point to the Earth's axis of rotation, since Moon is tidally locked to the Earth, and shows only one face to us (with a slight wobble, so that over time we see slightly more than 50% of it).  In effect, a gyroscope on the Moon would be describing same sort of path as one on the Earth, just at a different speed.  Since the Earth and the Moon both rotate in the same direction, and the Moon is tidally locked, they share the same celestial north pole anyway.  If there is a wobble related to the orbit around the Sun, then this might be more noticeable on the Moon, because the looping would be more extreme.


I am aware that the Earth's axis of rotation is not the same as the axis of orbit around the sun.  If it were, then we might still have summers and winters (due to the elliptical orbit), but they'd be at the same time for both the north and the south hemispheres.  As it is, the southern hemisphere is tilted towards the Sun during summer (the definition of summer) and the Earth is also closest to the Sun in January (which could be a definition of summer if we had no tilt to our axis, if we didn't call it summer, there would still be a term that means "when temperatures are generally higher than the annual average").

Thursday 14 January 2016

Argument from, well, the lack of evidence

In 1905, Albert Einstein published a few papers.  One of them was the basis of Special Relativity (On the Electrodynamics of Moving Bodies).  He had an idea and he argued for it, providing a thought experiment and some equations (Lorentz transformations).  At the end of the paper, he provided a prediction which could be experimentally tested, thus providing evidence in support of his theory if successful and falsification otherwise.  Other experiments were also possible, such as testing for time dilation.

Scientists performed these experiments, confirmed results consistent with Einstein's theory and Einstein moved on to General Relativity.

What they didn't do is provide endless variations on "Philosophical Argument for Special Relativity from ...".  This is because they didn't need to.  They had evidence.

It seems to me that the never-ending stream of arguments of the form "argument from …" merely highlight the fact that theists don't have any actual evidence.  The same applies with pseudo-clever pseudo-logical manipulations that masquerade as arguments (and are sometimes called for within "argument from …" arguments).

In a way, it's almost like the avid ghost-hunters and those people who try to track down the Loch Ness monster, or Bigfoot, may well be less crazy than some of our theist friends – they are at least trying to obtain evidence for their obsession.  Imagine someone trying to run an ontological argument for the existence of Bigfoot, completely crazy!  Going out into the forests and mountains to obtain evidence for the existence of Bigfoot is merely going to be unsuccessful (at least on the balance of probabilities).

Those arguing for the existence of god, however, seem to have no embarrassment about running these sorts of crazy arguments and then claiming that these arguments are in themselves "evidence"!  (Warning for uninitiated, apologists don't like being called crazy, I've tried it a few times and they tend not to respond well.)

I think this is one of my major reasons (at least now) for being such a strong atheist, bordering on being an anti-theist (that is I have a negative attitude towards certain types of theists, I'm not anti-god – that would be incoherent, I'm no more anti-god than I am anti-Santa or anti-satan, come to think of it – they're all imaginary).

Every time someone raises a new "argument from …" style argument for their god, I become that little bit more convinced that they are grasping at non-existent straws.

It's also interesting to note that many fallacies, which apologists love to bandy around, also are referred by apologists and other theists to as "argument from …" – a bit of a Freudian slip, perhaps?  That there might be bordering on an argument from ridicule, according to the site linked, an apologetic site, one that is arguing that the following is a logical fallacy:

"The definition of Christianity: the belief that a cosmic Jewish Zombie who was his own father can make you live forever if you symbolically eat his flesh and telepathically tell him you accept him as your master, so he can remove an evil force from your soul that is present in humanity because a rib-woman was convinced by a talking snake to eat from a magical tree."

To me this doesn't sound like an argument at all, it just sounds like ridicule.  An argument from ridicule might take this form:

If christianity is ridiculous, then it is false

If christianity is false, then god does not exist

Christianity is, by definition, the belief that a cosmic Jewish Zombie who was his own father can make you live forever if you symbolically eat his flesh and telepathically tell him you accept him as your master, so he can remove an evil force from your soul that is present in humanity because a rib-woman was convinced by a talking snake to eat from a magical tree

This is ridiculous

Therefore christianity is false

Therefore god does not exist

I think we can all agree that this argument has more problems than an appeal to ridicule, oops, I mean "argument from ridicule".  For example, a magic sky-fairy could possibly exist even if christianity were false.

Monday 11 January 2016

Poisoning the Well and Other Crimes

There is little else that a christian apologist likes more than a poor understood and woefully misapplied fallacy.  The case in point is the "poisoning the well fallacy".

What, I hear you ask, is the "poisoning the well fallacy"?  We'll get to that, but the question itself is interesting.  I've seen mention of this fallacy a few times recently, but only within a very limited range.  In other words, if you go to specific web-sites or forums and hang around for any amount of time, you will hear poisoning the well mentioned, but in the rest of your life, you may not hear it mentioned at all – unless you are an historian or you're a right-wing nut-job and/or christian apologist.

Most recently, I've been accused of the committing the fallacy myself.  Here's that accusation:

neopolitan,

“I’m astounded to see that this grant has, as its source, Templeton World Charity Foundation/Research Support…”

I’m astounded to see you questioning Luke’s objectivity when you can’t even recognize a poisoning the well fallacy in your own comments. Any mediocre high school student studying philosophy would’ve known to avoid this… you didn’t. If there are issues with Luke’s objectivity or funding they will reveal themselves in flawed datasets and/or faulty analysis. This is what you need to demonstrate if you want to make a credible case. So far you have not, here or at your own blog. In any event you certainly aren’t going to do so by questioning his motives, especially when they haven’t kept him from avoiding basic logical blunders you’ve fallen for or led to his published research failing peer-review.

If I were you I’d steer clear of poisoning the well not only because it’s fallacious, but because it can be turned against you with a great deal of force.

Luke is operating from “a covert position as a theist” you say…? Well he’s clearly stated that he’s a theist in this forum and elsewhere. His home page (linked from this blog) lists his CV, his research, his popular and refereed publications… everything one needs to vet his claims. If there’s anything “covert” in all that I’m not seeing it. Your blog on the other hand tells us… nothing. You show an email, an empty “About Me” section, an icon, and a note that says you’ve been on blogger.com since June 2012. No CV, no publications refereed or otherwise… nothing whatsoever that might tell us whether you’re qualified to speak on this or any other topic. As for the “objectivity” of atheism (yours or anyone else’s)… countless examples can be documented of where an atheist agenda led to all sorts of reckless scholarship, including (but not restricted to) ignorance of science, ignorance of philosophy and history, cherry picking, math errors, citing gossip spoof sites as legitimate sources, and even deliberately falsifying information, the latter of which is outright negligence.

You need to up your game Sir… ;-)

Well, thank you for your interest, Scott Church, of scottchurchdirect.com (apparently a gossip spoof site, but perhaps I am misunderstanding the intent of his link).  I was going to protest loudly about the list of crimes tacked onto the end of this comment, but it appears that Scott has protected himself by being vague as to who has committed these crimes.  At least the links he provides, when he provides them, indicate that there were other suspects (Richard Dawkins in one cherry picked example – the arguments in the God Delusion do not hinge on the specifics regarding the ravings of Pat Robinson – and Lawrence Krauss in another).

I find it interesting that, according to Scott Church, Luke Barnes is a theist and he (Barnes) has admitted as much somewhere on his blog.  Luke hasn't (so far) complained about that characterisation.  But then again, I've not seen him complain about being labelled as an atheist either, Richard Carrier has Barnes listed as an atheist.  But perhaps Barnes has complained privately.  J.W.Wartick mentions Barnes (now) as a "cosmologist blogger", but initially referred to him as an "atheistic blogger" (there's a link back service active on Letters to Nature).  It sort of makes sense for a theist like Barnes to go out of his way to correct his theist allies, but leave his atheist opponent's errors untouched.

I'd be interested to see where Barnes fully decloaks as a theist, if he actually has anywhere.  Perhaps Scott can be more forthcoming.

And then there's the question of covertness.  Scott accuses me of being covert, and by extension of hypocrisy because I have accused Barnes of being "a covert theist" (and here) – I have also accused him of being "a cloaked theist" – while maintaining anonymity on my part.

True, I am anonymous, but as a consequence I am not a public figure, I don't have a platform and less can be reasonably demanded of me.  Any arguments I make have to stand or fall on their own merits, I cannot point to my academic papers, or degrees, or the adulation of fawning wannabe apologists (if there were some sort of atheist equivalent to the fervent followers of people like WLC and those who support him in his apologetic mission, like Luke Barnes).  In any event, I am accusing Barnes of being coy about his theism and his theism is relevant because of his fixation with Fine Tuning.  He knows as well as I do that for anyone to be at all credible as a proponent of Fine Tuning they have to be working from a purely scientific background.  For this reason, I suspect, Barnes has wanted to keep his theistic leanings quiet.  If Barnes is a raving theist with apologetic aspirations, then his interest in Fine Tuning is tainted.  He knows it.  I know it.  But Scott Church either doesn't know it, or doesn't quite understand it.

And, thus, we come to poisoning the well.

Scott's complaint, as far as I can work out, relates to either my accusation that Barnes is a theist (thus pointing out that his work on Fine Tuning is tainted by his theistic partisanship) or my pointing out that Barnes is compromised by his association with Templeton.  Is either of these a case of poisoning the well?

I don't think so.  Let's look at Scott's link to the Wikipedia entry on what he calls the "poisoning the well fallacy".  We are told that:

Poisoning the well (or attempting to poison the well) is a rhetorical device where adverse information about a target is pre-emptively presented to an audience, with the intention of discrediting or ridiculing everything that the target person is about to say. Poisoning the well can be a special case of argumentum ad hominem, and the term was first used with this sense by John Henry Newman in his work Apologia Pro Vita Sua (1864). The origin of the term lies in well poisoning, an ancient wartime practice of pouring poison into sources of fresh water before an invading army, to diminish the attacking army's strength.

It's not strictly speaking a fallacy after all, but a rhetorical device.  However, it can be a special case of ad hominem, so perhaps we can let this slide.

There are other problems though.  Poisoning the well is supposed to be pre-emptive.  Nothing I've provided about Barnes has been pre-emptive.  Also, going from the example provided by Wikipedia, the poisoning has to be irrelevant to issue at hand – and Barnes' theism is not irrelevant to the issue at hand.  So, your Honour, I plead "not guilty".

I'd also like to point out that, in pointing out my anonymity the way Scott did, he may well have been attempting a bit of well-poisoning himself – perhaps as a demonstration of how they could be turned against me "with a great deal of force": You shouldn't listen to this guy, he's hasn't got a detailed history of himself on his blog and he hasn't told everyone his name!

My arguments don't rest on my personal history or my name, Mr Church, so your attempts fail.  Please try again.