Tet

Tet

Friday, 4 September 2020

"You Can't Prove Homeopathy Doesn't Work"

The title is the repeated mantra of homeopathists (i.e homeopaths and their apologists). The point is that we don't have to: they are shifting the burden of proof.

They make the claim that homeopathy works, so the burden of proof is upon them. Until then, as the late Christopher Hitchens put it, "That which is asserted without evidence may be dismissed without evidence."

I can only assume that homeopathists are ignorant of how proof of efficacy works.  This is not written for those people (even if they do understand it, they will likely pretend not to), but for open-minded people who are not aware of this. (This lack of awareness is not entirely surprising, given that this is not the sort of thing that is taught in school unless one is studying statistics, at A level in the UK, and probably a similar level elsewhere.) What follows is somewhat over-simplified, but serves to illustrate the point it seeks to make.

When one conducts a scientific test, one needs what are called "controls"; the purpose of these is to ensure that any changing observations are due to the parameter that the experimenter is changing. When testing pharmacologically active compounds for potential use as medicines, if it is ethical to do so the control usually takes the form of a placebo.

You may have encountered the saying that "you can't prove a negative". For this reason, the test takes the form of disproving a negative. The experimenter formulates what is called the "null hypothesis" (the negative). This takes the form of a testable statement of the form: "There is no statistical difference at a significance level of [p-value given] between [test substance] and placebo in their effect on [specify condition being tested]." (NB: Significance testing and "p-values" are minefields that are poorly understood by most people. If you are interested in why, there is a superb article on this on the Royal Society's website.)

The tests are then conducted, adhering to experimental protocols that are established before the test is conducted and should include "blinding" (neither the experimenter nor the test subjects know if the latter are being given the placebo or the test substance) and "randomising" (the selection of the control group is random in order to prevent bias). This adherence to protocols means that, for example, if you are testing something for its analgesic properties and you suspect from the outcomes that it may have, say, antihypertensive effects, you must design a new test for the antihypertensive effects.

A key point is that the experiment determines whether or not the null hypothesis (i.e. the statement that there is no statistical difference) is refuted. The outcome is binary, i.e. there are exactly two possible outcomes: either the null hypothesis is refuted or it isn't refuted. There are no other possibilities. If the null hypothesis is refuted, the test is deemed positive for the test substance. Otherwise, the test is deemed to be negative. There are no intermediate states such as the "inconclusive" one so beloved of quacks; what they term "inconclusive" is what honest researchers call "negative".

The test is then written up in detail and published to enable other scientists to evaluate and replicate it (outcomes that can't be replicated aren't a lot of use!).

Another key point is that the burden of proof of a claim is placed where it belongs, i.e. it is for the person who claims that a substance is efficacious to prove it, not for others to disprove the claim. The touts for homeopathy do not like this, but this simple fact remains:

There is no such thing as an independently replicated robust-quality double-blinded randomised control trial that demonstrates that homeopathy is distinguishable from placebo for any condition or purpose.

 

So how can we be sure that it doesn't work?

First of all, homeopathy is not medicine. It is a marketing tool for pseudomedicine that pretends that magic is real and relies upon the gullibility of the people whom its practitioners cynically target in the cause of profit.

It is made by serial dilution of an original substance (“mother tincture”) and “succussion”, i.e banging it against a resilient surface (the inventor, Hahneman, reputedly used a leather-bound Bible). This banging, we are told, transfers the “essence” (or “vitality”, depending on which homeopath is quacking) of the original substance to the solvent. Nobody seems to be able to tell you how many bangs are necessary for this magic to occur.

In the homeopathic “C” scale, each dilution is 1 part of “magic” per 100 parts of solvent, so by the time you get to 30C, the dilution is 1 part per 1060 parts of solvent. There are several problems with this:

  • The solvent would also dissolve minuscule amounts of the containing vessel; hence, if this was a glass vial, borosilicate glass would be dissolved. For some unexplainable reason, the “magic essence” from the borosilicate is selectively excluded from being transferred to the solvent.
  • Back to the 1060: if a sphere the size of Earth’s orbit around the Sun was filled with water, it would contain “only” 4.25x1049 molecules, i.e. in a sphere that big containing the homeopathic “remedy”, there would be less than a 1:10,000,000,000 chance of a single molecule of the original substance existing.

We are then invited to suspend our critical faculties and believe that further serial dilution and succussion makes the substance more potent. The 30C dilution previously mentioned is referred to, by homeopaths, as a “low potency”. Something like the flu remedy touted by Boiron (a multi-million pound/dollar/euro manufacturer of this implausible magic) is what the homeopaths call “high potency”: 200C, ie a concentration of 1 part per 10400 . Given that there are only about 1080 atoms in the known Universe, you would need 100,000 Universes to have a probability of one molecule of the original substance existing!

Obviously, this is nonsense. Nothing can be diluted even as far as the “low potency” 30C level. The homeopaths try to get around that by pretending that water in the solvent has a magic memory of what has been dissolved in it. Somehow this memory is very selective: it remembers only the stuff the homeopaths wants it to remember and selectively forgets all the other stuff that it has dissolved in it (so-called “pure” water is never actually 100% pure). Remember the borosilicate! Anyone who believes this guff cannot possibly have a brain, but merely skull-water with the memory of a brain.

One of the apologists for homeopathy that regularly posts on Quora states that this water memory phenomenon was endorsed by winner of the Nobel prize for Physics, Prof. Brian Josephson, FRS. It was, but what the apologist neglects to tell us is that Josephson did not actually study it, but merely attended a lecture given by a proponent of the water-memory hypothesis, Jacques Benveniste, who published a paper on the subject in Nature. When corroboration was sought, it could not be found and neither Benveniste nor anyone else has been able to replicate it.

A very short duration “water memory” phenomenon does appear to exist, but it endures for only a few femtoseconds.

Water memory of the type proposed by homeopaths exists only in the homeopaths’ own deceptions (and delusions?).

Could there be some other explanation? Homeopaths claim any number of things, almost always from a position of profound ignorance of the science involved, ranging from quantum mechanics, through some as-yet undetectable “energy”, to an unknown mode of operation unknown to science (or anything else, for that matter). They can produce no evidence, or even a plausible scenario, for any of these things.

For homeopathy to work, most of what we know about chemistry and physics, including the bits that enable me to post this blog and you to read it, would have to be wrong: if homeopathy was plausible, the modern world could not exist. 

 

So why do some people believe in this stuff?

I contend that there are three main things that contribute to the anti-scientific magical-thinking belief that homeopathy works:

  1. The disinformation and dishonest marketing ploys used by the touts for homeopathy.
  2. A combination of human credulity/gullibility and the failure of science education to adequately counter this.
  3. A phenomenon whereby people tend to credit the last “remedy” or “treatment” they took for the “cure” (aka the post hoc ergo propter hoc fallacy). If, for example, somebody is taking medicine for a condition, but does not seem to improve, but then tries a pseudomedical intervention like homeopathy and seems to improve, they attribute the improvement to homeopathy and not to the possibility that the medicine takes a while to work. Similar phenomenon with self-limiting conditions.

This explains why the "skill" of a "good" homeopath lies in "treating" self-limiting (or, better, non-existent) ailments with nothing. For profit. Then you have the other kind of homeopath. These will pretend to be able to treat anything from malaria to autism to cancer with nothing. For profit.

It's worth repeating:

There is no such thing as an independently replicated robust-quality double-blinded randomised control trial that demonstrates that homeopathy is distinguishable from placebo for any condition or purpose.

Monday, 13 March 2017

Response to Consultation: The use and promotion of complementary and alternative medicine: making decisions about charitable status

Today, 13th March, 2017, the Charities Commission (the Commission) announced that it is conducting a Consultation on complementary and alternative medicines. This will run until 12:00am 20th May 2017, so responses should be submitted by 19th May, 2017.

This existence of this consultation is due to submissions made by lawyers acting for the Good Thinking Society, which writes:
This consultation represents an opportunity for organisations and members of the public to make their thoughts on CAM charities known to the Charity Commission. This is an opportunity supporters of pseudoscientific charities will almost certainly take up, so it is vital that supporters of science and evidence-based treatments get in touch with the Charity Commission in order to ensure our views are well represented.
My responses to the Commission follow. I'm sure you can improve on them.



Question 1: What level and nature of evidence should the Commission require to establish the beneficial impact of CAM therapies?

Ideally any evidence of beneficial impact should be in the form of replicated, good quality, double-blinded, randomised placebo-controlled trials that demonstrate that the therapy is distinguishable from placebo for the medical condition for which it is being offered. This should be published in a recognised medical journal such as The Lancet, the British Medical Journal, or the New England Journal of Medicine.


Question 2: Can the benefit of the use or promotion of CAM therapies be established by general acceptance or recognition, without the need for further evidence of beneficial impact? If so, what level of recognition, and by whom, should the Commission consider as evidence?

No. "General acceptance or recognition" falls under the umbrella of the "Bandwagon fallacy" (argumentum ad populum), i.e. the fallacy that something should be considered to be true or beneficial because it is widely believed to be true or widely used. Benefit can only be established by replicated, good quality, double-blinded randomised placebo-controlled trials that demonstrate that the therapy is distinguishable from placebo for the medical condition for which it is being offered.

In particular, accreditation of CAM trade bodies (e.g. the Society of Homeopaths, the General Chiropractic Council) by bodies like the Professional Standards Agency, the Complementary and Natural Healthcare Council and the British Complementary Medicine Association must never be accepted as evidence of benefit, because these bodies do not require evidence of efficacy or benefit as a condition of accreditation.


Question 3: How should the Commission consider conflicting or inconsistent evidence of beneficial impact regarding CAM therapies?

Firstly, the burden of proof lies entirely with the proponent of the CAM therapy. The proponent must demonstrate that the therapy concerned is distinguishable from placebo for the medical condition for which it is being offered.

If the robust evidence is conflicting or inconsistent, this should be resolved by an independent (e.g. Cochrane Collaboration) meta-analysis that gives additional weight to higher-quality trials. In the absence of a meta-analysis, the adjudication of the Government Chief Scientist should be sought.


Question 4: How, if at all, should the Commission’s approach be different in respect of CAM organisations which only use or promote therapies which are complementary, rather than alternative, to conventional treatments?

It should not differ at all. The Commission's sole criterion must be that of demonstrable benefit over and above that of placebo for the medical condition for which it is being offered.


Question 5: Is it appropriate to require a lesser degree of evidence of beneficial impact for CAM therapies which are claimed to relieve symptoms rather than to cure or diagnose conditions?

It would not be appropriate.  The Commission's sole criterion must be that of demonstrable benefit over and above that of placebo for relief of the symptoms for which the CAM therapy is being offered.


Question 6: Do you have any other comments about the Commission’s approach to registering CAM organisations as charities?

Yes.

1. The absence of any mandatory reporting of harmful or adverse effects of CAM make it impossible to weigh benefit against harm for the simple reason that the harms are unknowable. The Commission must therefore not accept submissions that any CAM therapy either causes no harm or has more benefits than harms.

2. The Commission should not register CAM organisations which either promote their own therapies over, or seek to denigrate, evidence-based medicine.

Monday, 19 May 2014

Homœoneologisms


In addition to creating a new form of pseudomedicine, in order to protect it from reasonable debate, its touts and apologists have devised a whole new set of fallacies, red-herrings and diversionary tactics. In order that we need not describe them in full every time we meet them, some are named for convenience (rather in the same way that "homeopathist" (not itself a neologism) is shorthand for "touts, purveyors and apologists for homeopathy"). Here are some of them.

BrownBagging (aka "Hermann-Courtney Insufficiency"): A bizarre, clueless and complex hotch-potch of Dunning-Kruger compliance, Scopie's Law and its Corrolaries, Willberging (qv) and Poe's Law, occasionally modified by Hanlon's Razor and its variations. 

Bruckering: Finding that you're getting hammered in a debate, so calling for reinforcements and, when your quackdogs arrive, leaving them to carry the can while you skulk off to postures new.

Dullmann Index: An informal assessment of the degree of inappropriate (i.e. all of them!) citations or explanations that attribute a theory of how homeopathy works to quantum physics, nano-pharmacology, and other terms from modern science. The unit of measure of the Dullman Index is the milGrom.

Inane Lewis Manoeuvre: Posting, in an online discussion, a link in which you have posited some personal information, then trying to divert attention away from criticism of homeopathy by accusing anyone who notices it and subsequently comments on it of "snooping" on you.

Jahnigging: Posting huge gish-gallops of links that supposedly support some unscientific notion or fruit-loop conspiracy theory but which, on inspection, do nothing of the sort (which was pointed out the last time they were posted). (Intimately associated with Redding (qv) - in fact, so intimately that you would be forgiven for thinking that they were the same thing.)

Redding: Citing impressive sounding documents (often from international organisations like the WHO) which, on inspection, turn out never to have existed. (e.g. go here and search on "WHO report") (Intimately associated with Jahnigging (qv) - in fact, so intimately that you would be forgiven for thinking that they were the same thing.)

Tactical Janissing: Scattergun gish-galloping of a wide and varied spew of unevidenced bullshit, ranging from ridiculous claims that different sceptics are one person to Jahnigging (qv), all designed to try to hide the fact that the spewer has been spouting a wild hotch-potch of bullshit.

Willberging:  Repeatedly getting caught out bullshitting (mostly because the bullshit is usually so mind-numbingly stupid that you'd have to be two neurones short of a synapse to believe it in the first place, eg here and here), then blithely and shamelessly continuing without a shred of contrition, as if it had never happened.

I suspect there will be more....

Edit: ...and indeed there are:

Venkatosh: Claiming the ability to identify homeopathic "remedies" if, and only if, collusion is possible.



Edit (Suggested by Lee Turnpenny):

Ros(s)ing: A noisy, dishonest deflection device, characterised by mantric accusations of ‘ignorance’ and ‘prejudice’, employed to obfuscate copious logical fallacies and feigned oblivion to failure to address and correct untruths.

Thursday, 15 May 2014

Venus: Stellar Errors — Pseudomedical Misuse of Astronomy (and Logic)

Homeopathy is a pseudoscientific system of medical quackery that claims to work on the principle that if a substance makes a healthy person ill, it will cure a person with that illness. In homeopathic jargon, this is "the law of similars" and is often stated as "like cures like".

Homeopaths compound this illogic by claiming that, if a solution of this pathogenic agent is diluted and "succussed", their jargon word for hitting the vessel that contains the solution against an elastic body (apparently this was originally a leather-bound bible), it somehow becomes more effective. Homeopaths call this process "potentisation". We are invited to believe that a solvent, so dilute that were it larger than the known universe the probability is that it would not contain a single molecule of the original pathogenic agent, has somehow become more "potent". Homeopaths assert that this is due to the substance leaving its "imprint" on the solvent. They misrepresent (e.g here and here) physics to claim that this is due to the "memory of water", conveniently ignoring the evidence that any "memory" that water possesses lasts, at the most, for a few picoseconds. Exactly how the solvent remembers only the homeopath's pathogenic agent and conveniently forgets all the other stuff it's had dissolved in it for millions of years, or the atmospheric gasses that must be come into contact with it during the "potentisation" process is something that, unsurprisingly, is not adequately explained.

One can easily understand the appeal of such claims. Homeopaths usually hawk their remedies in either an aqueous solution of ethanol or on pillules of sucrose. There is an enormous profit to be made in selling aqueous ethanol or sugar for several hundred £, € or $ per kilogram. (See note)

Furthermore, it is now no longer necessary for the homeopath to actually have the original pathogenic substance: it is now possible to buy for £1000 or more, a machine that is claimed to use something akin to radionics to imprint sugar pills with the "vibrational energy" of the desired substance at whatever "potency" the user wishes.
In their quest for new "remedies", and perhaps also for fame in the pseudomedicine community, homeopaths seem to be on the lookout for wackier things to use. One of these has been starlight from Polaris — you couldn't make this up! I was unable to get in touch with the author of that particular example of homeopathic quackery, but have had more luck with an enterprising English homeopath, Chris Wilkinson, who has created another "remedy" using, I kid you not, the Light of Venus. Following the pretentiousness that seems to infest most so-called pseudomedicine (presumably some misguided attempt to create a veneer of academic authenticity) Mr Wilkinson has Latinised the name of his "remedy" to Venus Stella Errans (or "Planet Venus" in plain English). Mr Wilkinson is very active on Twitter, where he valiantly defends his chosen species of pseudomedicine, so I took the opportunity to quiz him about this "remedy".

Mr Wilkinson's description of his experimental process is strangely lacking in any of the detail that would enable his experiment to be replicated. In a Twitter exchange on the 25-27 June 2012, Mr Wilkinson seemed reluctant do divulge much more asserted that this is not necessary on the grounds that "any homeopath who knows about remedy making would have enough info to make something close enough … also the remedy doesn't have to be made again for a very very long time, way after we are dead" and that "there were too many minor variables involved to precisely replicate". So that's alright, then! However, I did manage to elicit some experimental detail:
"The telescope was a reflector, about 18in. The lactose was on the eyepiece."

I asked what part of the eyepiece (Eye lens, field lens, field stop, somewhere else?); Mr Wilkinson replied:
"the bit your eye looks in! No idea what that was called. It was slightly curved? … convex i mean"

In response to a question about how he had exluded other light from the lactose and during the "potentising", Mr Wilkinson responded: "It wasn't "completely" dark of course. Likewise with the initial potentising."

"The perpetrator of the Polaris drivel (above) stated:
The procedure was as follows. Having at my disposal an eight-inch Schmidt-Cassegrain Celestron telescope, I inserted a half-inch diameter clear-glass vial encircled by a cork rim into the eyepiece aperture. For autumn viewing the vial was filled with well water; in the winter, I used vodka, neat, to prevent the fluid freezing. The telescope itself was set up in the middle of a free-standing stone enclosure some three feet high and forty feet in diameter, which was oriented on a north/south axis.
"By means of the finderscope I kept the telescope contered on a chosen star for an interval of one hour. At the end of the viewing period I removed the vial from the telescope and to avoid human contamination placed it in a plastic container filled with sand. "

For a moment, let us suspend our critical senses and incredulity and assume, for the sake of argument, that homeopathy might work and that starlight or sunlight reflected from Venus might work homeopathically. The sunlight that Mr Wilkinson "collected" in his lactose took this route:
  1. Several million years transiting from the core of the Sun to its surface, where it was radiated into space.
  2. Impinged on the visible surface (i.e. atmosphere) of Venus, where about 25% was selectively absorbed and the other 75% reflected into space.
  3. Some of this reflected light then entered Earth's atmosphere; a tiny amount would have been selectively reflected, some selectively absorbed, some selectively scattered and some would heve entered the aperture of Mr Wilkinson's telescope, either directly or as a minuscule part of the scattered light.
  4. This light would then be reflected off the aluminium coating on the primary mirror (double-passing through any quartz overcoat) and again off the aluminised surface of the secondary mirror.
  5. It would then pass through layers of optical coatings on the eyepiece and through the several lens elements which, in modern eyepieces are of at least two different types of glass. Each of these would selectively absorbed some of the light, and each optical surface would have reflected some.
  6. It then passes onto the surface of Mr Wilkinson's lactose, where it mixes with the ambient light.
Even if Mr Wilkinson's "remedy" had some effect (and he has not, to the best of my knowledge, published, in any scientific journal, any RCTs with evidence of efficacy), he would have no way of knowing whether the effect was due to :
  • Reflection off Venus's atmosphere
  • Reflection off the aluminised mirror surfaces
  • Reflection off any other optical elements
  • Selectivebsorption by the atmosphere or any of the optical elements the light transited
  • Other scattered light from the atmosphere
  • Ambient light that the lactose absorbed from the time of its manufacture, up to and including the process of "potentisation"
In short, the design of this experiment is so poor that it beggars belief! As far as I can tell, there are no controls at all. Applying the homeopathic theory that "more dilute" equates to "more potent", the reflected sunlight from Venus would be amongst the least active of the different "lights" in the solution!

The "Polaris" one is even worse: the experimenter used water from a well! How did it manage to "forget" all the myriads of compounds that are found in any well water and "remember" only the starlight of Polaris?

If this shoddiness and appalling lack of control is typical of the design of homeopathic experiments or in the manufacture of their "remedies" (and I have no evidence to suggest that it is not typical), we should not be surprised at any outome. In my Twitter exchange with Mr Wilkinson, he seemed unconcerned about experimental rigour and much more concerned that I should have experienced homeopaths supervising any subjects I "proved" the "remedy" on ("Can go thru variables at some point, tho thats far less an issue than the proving process")if I decided to make it and test it. (To homeopaths,"proving" is the process by which they decide which "remedies" will treat which symptoms. Again, as far as I can ascertain, it is a shoddy process where experimental rigour is concerned. Although homeopaths try to claim that they are equivalent to clinical trials, they are not randomized, not blinded, highly subjective and prone to expectancy bias. As long as 170 years ago, Oliver Wendell Holmes stated that they are not repeatable and are too vague to be useful.



Note: I do not assert that all, or even most, homeopaths are knowingly committing medical fraud. However, I do assert that they are committing quackery, as defined by Quackwatch:"  Most people think of quackery as promoted by charlatans who deliberately exploit their victims. Actually, most promoters are unwitting victims who share misinformation and personal experiences with others."   I also assert that, most people of integrity who claim efficacy for homeopathy and much other pseudomedicine would not do so if they had a full understanding of the placebo effect which, contrary to what supporters of pseudomedicine try to tell us, also works on animals and children.

Monday, 14 October 2013

What 'What Doctors Don't Tell You' really told you


Last updated 2013 October 17 09:05 UT


The tacky health-scare magazine self-styled "journal", What Doctors Don't Tell You, has been getting a little hot under the collar recently about things that it claims it is reported to have said but didn't really say. It's also been making some rather surprising assertions about other things. Some of these are clearly silly "couldn't be bothered to check"-type errors, others are more than that. You be the judge.

This post will be added to as time and information permits.


The Claim The Reality
McTaggart (said) her journal would accept no advertising - "we have to remain pure" - Not only is approximately a quarter of each issue devoted to advertising (based on June 2013 issue), in February 2013, the Nightingale Collaboration reported that the Advertising Standards Authority had adjudicated against advertising in WDDTY to the tune of 54 CAP-Code breaches. This is in addition to eleven "informally resolved" cases (i.e. the advertising was acknowledged to be in breach of CAP-Codes and was amended voluntarily.)
"...the Nightingale Collaboration, a ragtag group who meet in a pub of the same name..." Errr.. there is no pub called The Nightingale Collaboration.
"...the pharmaceutically backed organization [Simon Singh] fronts, 'Sense About Science'...." Sense About Science is a charity. Its accounts are therefore open to scrutiny.




Less than 5% of its funding comes from companies; none of these is a pharmaceutical company.
WDDTY complained: "The Times stated: we said vitamin C cures HIV."

"Five Live followed up with a television debate about our magazine." Five Live doesn't do TV debates. (Clue: It is a radio station!)
"It's also apparent from the information published in The Times and in all the media following that not one journalist or broadcaster has read one single word we've written, particularly on the homeopathy story, and for very good reason: the article and the magazine containing it in fact have not yet been published." Ummm -- WDDTY published their claims for homeopathy months ago!



And bragged on Facebook about doing so!




(To the Times) 

"You have no idea yet what we're going to write about, so how can you say we're going to write that homeopathy 'cures' cancer?"
Ummm... Maybe they were referring to a claim WDDTY has already made? (See above)




"Just to clarify yet another lie about us: we are not 'pro' or 'anti' vaccine." From WDDTY, June 2013: "The safest interpretation is that the MMR increases the risk of autism by 5 per cent"










"Not one of the newspapers, radio shows or television stations bothered to contact us, even to solicit a comment,,," The Times journalist who reported on the campaign to get the magazine off supermarket shelves sent this email:


And phoned twice:
 

(Having had no reply from the "Editorial" department, he next tried "Accounts and General Management")



"...the Swiss government decided that there is some proof of homeopathy..." It did nothing of the sort! See Zeno's Blog for what really happened.
"For months, Singh, whose Sense About Science group has the sponsorship of the British Pharmaceutical Association..." If the The British Pharmaceutical Association actually exists and is not just something else made up by McTaggart, it is not a sponsor of Sense About Science.
"[Waitrose] are not one of our stockists" Curious. That's not what the distributor thinks:

"The letter being sent out by the Times to our readers..." The Times is sending out letters to WDDTY readers?
Really?
Is WDDTY implying that the Times somehow get hold of the WDDTY subscriber database?
Has anyone ever actually seen one of these letters?


What does become apparent is that WDDTY needs some sort of disclaimer on a lot of what it asserts!

Friday, 2 August 2013

Simple Test for the Efficacy of Homeopathy

Take the "Tetenterre Challenge"

  • Homeopaths claim that their so-called "remedies" are effective. 
  • By definition, something that is effective has an effect. 
  • If something has an effect, that effect can be observed.

This offers a simple double-blind, randomised test for the claims homeopaths make:
  1. An experienced homeopath selects sufficient quantities for a dozen provings of two remedies whose provings show them to have very different, preferably opposite, effects.
  2. This homeopath selects eleven homeopath collaborators.
  3. A researcher, using techniques determined by the homeopath, distributes the pillules of each remedy into a dozen separate identical new vials.
  4. A placebo (physically identical "inert" pillules) are distributed into another dozen identical new vials.
  5. The vials are individually randomly labelled by the researcher with identification numbers.
  6. The researcher records, for each ID number, whether it holds Remedy #1, Remedy #2, or Placebo.
  7. The vials are randomly grouped into threes, each group containing one vial each of Remedy #1, Remedy #2, Placebo.
  8. The homeopath collects a package containing the vials (no contact with the researcher).
  9. The homeopath distributes the groups of vials to his/her homeopath collaborators.
  10. Each homeopath, conducts "provings" of the contents of each vial.
  11. The homeopaths use the results of the provings to identify which vials hold the placebo and which vials hold which of the two known remedies.
  12. The homeopath's identifications are compared with the researcher's records.

Any takers?

(Yes, I know that there are more holes in this than in a decent roquefort, but if homeopaths can't distinguish between "remedies" with this....)

Tuesday, 2 July 2013

The Human Eye: Evolution or Spectacularly Unintelligent Design?

As a visual amateur astronomer, I return time and again to considering the structure and spectral response of the human eye. It soon becomes clear that anyone postulating that it was created by some sort of divine entity must conclude that the divine entity is either spectacularly ignorant about the nature of light and its interaction with matter, or is just a bloody-minded sod that has chosen to endow its pinnacle of creation with substandard eyes. With a bit of thought, it could have done so much better — it's not as if it didn't know how!

Structure

Firstly consider the retina:






(Image Source: Public Domain Image from Wikipedia Commons; author: Santiago Ramón y Cajal)


As you can see, the main light receptors (rods & cones) are not situated on the front surface, but behind (in the simple model, above) three other (non-transparent) layers of tissue: The light has to pass through four layers before it is received by the photoreceptors. (If you want a more complex model, it's 9 layers, but that doesn't really make any difference to the argument).

Another consequence of this arrangement is that the nerve fibres are in front of the receptors. This means that they have to pass through the receptor layer, thus creating the Blind Spot. Hmmm -- clever? Nah, not really. Stinks of evolution!

Spectral Response

Now let's consider the response of the different cones to different wavelengths (colours) of light. Human vision has a range of approx 420nm to 680nm. We are trichromats, which means we have 3 types of colour receptor (called "cones"), with peak responses at approximately  430nm, 545nm and 572nm. Why would an intelligent designer create the clumping around 550nm? The usual excuse is that this is where the Sun's peak output is. This is simply incorrect: it is 504nm. Anyway, even if it was correct, we would not need 2/3 of our colour vision receptors to be closely packed around that wavelength.










(Image Source: Public Domain Image from Wikipedia Commons; author: Ben Rudiak-Gould)



So, how could it have done better? The answer is: "Really Easily!" It had lots of practice. After all, in its wisdom, before it created us, this divine entity supposedly also created the birds, the fishes and the insects, many of which are tetrachromats (four kinds of cone) and some are even pentachromats (five kinds). The finch, for example, has its peak colour responses more evenly spaced:











(Image Source: Public Domain Image from Wikipedia Commons; author: Ben Rudiak-Gould)




So, why did this divine entity give us such relatively poor vision, when it could so easily have done better?

Or did our vision just evolve, with inherited characteristics from folivorous and frugivorous mammalian ancestors, for whom an ability to finely discriminate colours in the yellow-green would have conferred an evolutionary advantage?