Dawkins on Theology

The British Independent recently ran an editorial not worth reproducing in the Skeptic. The editorial did, however, generate a vigorous response from Richard Dawkins which is worth thinking about.

Sir: In your dismally unctuous leading article asking for a reconciliation between science and “theology,” you remark that “people want to know as much as possible about their origins.” I certainly hope they do, but what on earth makes you think that “theology” has anything useful to say on the subject? Science is responsible for the following knowledge about our origins.

We know approximately when the universe began and why it is largely hydrogen. We know why stars form, and what happens in their interiors to convert hydrogen to other elements and hence give birth to chemistry in a world of physics. We know the fundamental principles of how a world of chemistry can become biology through the arising of self-replicating molecules. We know how the principle of self- replication gives rise, through Darwinian selection, to all life including humans.

It is science alone, that has given us this knowledge and given it, moreover, in fascinating, overwhelming, mutually confirming detail. On every one of these questions, theology has held a view that has been conclusively proved wrong. Science has eradicated smallpox, can immunise against most previously deadly viruses, can kill most previously deadly bacteria.

Theology has done nothing but talk of pestilence as the wages of sin. Science can predict when a particular comet will reappear and, to the second, when the next eclipse will occur. Science has put men on the moon and hurled reconnaissance rockets around Saturn and Jupiter. Science can tell you the age of a particular fossil and that the Turin Shroud is a medieval fake. Science knows the precise DNA instructions of several viruses and will, in the lifetime of many present readers of the Independent, do the same for the human genome.

What has “theology” ever said that is of the smallest use to anybody? When has “theology” ever said anything that is demonstrably true and is not obvious? I have listened to theologians, read them, debated against them. I have never heard any of them ever say anything of the smallest use, anything that is not either platitudinously obvious or downright false.

If all the achievements of scientists were wiped out tomorrow there would be no doctors but witch-doctors, no transport faster than a horse, no computers, no printed books, no agriculture beyond subsistence peasant farming. If all the achievements of theologians were wiped out tomorrow, would anyone notice the smallest difference?

Even the bad achievements of scientists, the bombs and sonar-guided whaling vessels, work! The achievements of theologians don’t do anything, don’t achieve anything, don’t even mean anything. What makes you think that “theology” is a subject at all?

Richard Dawkins, Oxford

Skepticism and Miracles

This article is an abridged version of the fourth article in a series on philosophy and the paranormal. Here Dr Grey discusses David Hume’s analysis of miracles and his view that belief in miraculous events is always unjustified. He also investigates the nature, virtues and dangers of different skeptical viewpoints.

Hume’s Razor

What is a miracle? In the vernacular we speak of “miraculous” escapes and the like, to characterise events which are extremely unlikely — at odds with the normal course of experience. A miracle in this weak sense just means a very improbable event.

David Hume, in his famous essay “On Miracles”, had a stronger sense of “miracle” in mind, namely something which violates a law of nature. It is in this sense that miracles have commonly featured in religious systems of belief, as the means by which God has been thought to have demonstrated His presence or His power to His chosen people.

The question which Hume addresses is: are we justified in believing that miracles have in fact occurred? He argues for the very strong conclusion that we are never justified in believing that a miracle has ever occurred.

Hume is not claiming to show that miracles have never occurred. Proving negative existence claims is notoriously problematic. Hume’s claim is the importantly different one that we are never rationally justified in believing that miracles have occurred. That is, Hume is addressing the epistemological issue of what it is rational to believe, rather than the metaphysical question of what is and is not possible in our sort of world.

The argument has two parts. First, Hume argues that the evidence against miracles is usually very strong. (And according to one of Hume’s epistemological maxims “a wise man proportions his belief to the evidence.”) We therefore have to weigh the evidence that a miraculous event happened against the evidence that it did not.

In evaluating testimony for miracles, Hume advances the following principle which, echoing the famous methodological principle commonly attributed to William of Ockham (c. 1285-1349), has been called Hume’s Razor. The principle is:

No testimony is sufficient to establish a miracle unless that testimony be of such a kind that its falsehood would be more miraculous than the fact which it endeavours to establish.

The second stage of the argument claims that even though the evidence in favour of miracles might outweigh the evidence against them, in practice this never happens. Hume maintains that there never was a miraculous event established on sufficiently strong grounds to warrant rational belief in its occurrence. There are four factors which undermine the credibility of any claim in support of the miraculous.

First there is the problem of witness credibility. Witnesses who testify as to the occurrence of miracles are seldom totally above suspicion of either having been deceived or of the intent to deceive. In evaluating their testimony, we must always choose between believing that a miracle occurred or believing that the witnesses were deceived or deceitful.

According to Hume, no miracle has ever been “attested by a sufficient number of men, of such unquestioned good sense, education and learning as to secure us against all delusion in themselves; of such undoubted integrity as to place them beyond all suspicion of any design to deceive others…” All claims for miracles, that is, suffer from what we call a credibility gap.

The second problem which Hume identifies is human credulity. There is a natural human affinity for the novel, the surprising and the marvelous. Recognising this propensity for credulity, we must take note of and be guided by the following maxims in evaluating claims for the miraculous:

  • Objects of which we have no experience resemble those of which we do have experience;
  • What we have found to be most usual is most probable;
  • In case of dispute, give preference to the side favoured by the greatest number of observations.

These sound, if somewhat pedestrian, maxims are frequently overridden by the excitement and novelty which is often the basis of human credulity.

Hume’s third point about miraculous claims is the tribal origins of superstition. Miracles occur mainly in primitive (in Hume’s words “ignorant and barbarous”) nations, or are derived from barbarous and ignorant ancestors. As human understanding develops, we come to reject omens, oracles, astrology, demons, and the like as unhelpful in explaining natural phenomena.

Finally, Hume points to a problem which confronts claims of the miraculous concerning conflicts of testimony. It is impossible that the religious traditions of “ancient Rome, of Turkey, of Siam, and of China” should all of them be established on any solid foundation. Every miracle claimed within any one of these traditions is intended to establish the truth of that tradition and to discredit the claims of the others.

Hume believed that the inclination of mankind towards superstition and the marvelous may receive some check from sense and learning, but he also seems to have believed that it could never be thoroughly extirpated from human nature. Hume, one suspects, would not be surprised to find beliefs in astrology, UFOs, crystals, channeling, and similar credulous ideas in the twentieth century.

The Virtues of Skepticism

Skepticism can be characterised as a critical stance with regard to knowledge (or existence) claims, and a skeptic is one who calls such claims into question. Skepticism can refer to either the critical stance adopted in subjecting knowledge claims to careful scrutiny, or to a state of doubt or disbelief which may be the outcome of such an inquiry.

Being skeptical in the second sense (withholding assent, or suspending belief in a particular claim) need not involve believing the opposite. Skepticism is a matter of doubt rather than denial. If I withhold assent from the claim that God exists, it need not be the case that I believe that God does not exist. I might believe that the evidence is just not strong enough to settle the matter either way.

We need to distinguish between critical and dogmatic skepticism, and between selective and global skepticism, though these terms do not mark absolute distinctions.

Skepticism is dogmatic if assent is withheld a priori, that is, on the basis of prior conviction without considering the evidence. For example, Galileo’s colleagues expressed a perfectly intelligible skepticism about the existence of the moons of Jupiter; they became dogmatic when they refused to look through his telescope.

Skepticism is global if it is general and encompasses all claims to knowledge; selective if it is targeted to specific knowledge claims.

Global skepticism is rare. Perhaps Cratylus, an older contemporary of Plato (c. 428-348 BC), is the most global skeptic recorded in the annals of philosophy. His skepticism is said to have been so extreme that he refused to answer questions and would only wave a weary finger at his interlocutor to indicate that truth was so elusive and ephemeral that it would be useless to reply. (At least, that is what his interlocutors are reputed to have believed him to have been attempting to say).

Skepticism which falls short of the global always has to be qualified by specifying the subject matter to which it is directed. There are various beliefs, for example about rocks and tables, which are immune to skeptical doubts — at least outside philosophy seminar rooms.

At the other extreme there are tooth fairies, Santa Claus and the elixir of life, which most will immediately dismiss as lacking sufficient epistemic warrant. In between (drawing boundaries here will create controversy) there are various disputed cases and claims, such as God, economic rationalism, J-curves, nuclear deterrence and psychic and paranormal phenomena. Disputed cases are also the coal-face of the professional philosopher: on which side of the dividing line, for example, should we put minds, beliefs, desires, meanings, properties, and numbers?

Strange Claims

When confronted with a claim about some strange, paranormal or similarly anomalous phenomena (an accurate premonition, a “near death” or an “out of body” experience, say), we should adopt a scrupulously skeptical approach. By this I do not mean that we must conclude that the experience did not occur, or that whoever had the experience must have been somehow deluded — though do not rule that out either! Rather, we should be alert to the possibility of natural and ordinary explanations of unnatural and extraordinary occurrences.

We must be especially careful in evaluating the evidence which appears to support such anomalous events. While rejecting a dogmatic skepticism which refuses to countenance anomalous events, critical skepticism seeks to gather as much evidence as possible concerning any extraordinary or allegedly paranormal event, claim or theory.

Critical skepticism means keeping an open mind not rejecting disputed claims a priori. We must examine the evidence scrupulously. But it means refusing to accept as true claims for which there is insufficient or ambiguous evidence, and recognising that withholding belief is preferable to accepting claims for which there are not sufficient grounds.

It also means adopting as a methodological maxim the principle that in seeking explanations we should prefer the ordinary to the extraordinary, and the simple to the complex. This is one interpretation of the principle known as “Ockham’s Razor”.

Skepticism is the disposition, or art, of matching belief to evidence. There is at present no convenient antonym for “skeptic”. For convenience, I propose to revive the archaic expression “credulist” to serve this role. A credulist can be understood as someone who is apt to accept claims without sufficient evidence, that is to say, someone whose epistemic standards are too low.

Why be Skeptical?

Etymologically, skeptikos means “inquirer”, and the value of skepticism is that it leads to — and when seriously entertained is usually the result of — a systematic inquiry into the foundations of knowledge. Skeptical arguments play a central role in inquiry, particularly philosophical inquiry where they have been directed not just at eccentric belief systems, but at beliefs which most regard as self-evident. Thus skeptical arguments have been raised about the existence of other minds, knowledge of the past, knowledge of material objects (the “external world”), moral truths, sensory knowledge and even about knowledge of logic and mathematics.

The purpose of skepticism in these cases is (usually) not to raise extravagant doubts (though that is sometimes an unintended consequence), but rather to clarify our understanding of the subject of inquiry. There are apparently more modest forms of skepticism which challenge, for example, theological or metaphysical knowledge. And in some cases (for example, I suggest with respect to astrology or phrenology) skepticism seems to be not merely defensible, but appropriate.

When pressed to extremes, skeptical arguments sometimes turn out to be self-defeating, and the critical pursuit of knowledge leads to a denial that knowledge is attainable. Extreme or global skepticism has often been the consequence of setting unreasonably high standards as to what is acceptable as knowledge — in particular setting absolute certainty (the impossibility of being mistaken) as a requirement for genuine knowledge.

Objections to Skepticism

Routine rejoinders to skeptics are, first, the claim that skeptics demand unrealistically high standards of proof (often accompanied by the charge that the skeptics’ insistence on these standards is unjustified), and, second, an insistence (sometimes dogmatic) that a disputed category of experience (a psychic experience, say) is more certain than any skeptical argument which calls them into question.

Regarding the first point, the insistence of protocols, controls, and repeatability are based on the beliefs that nature is consistent — and human nature often suspect. No one demands 100 per cent repeatability. There are always anomalous observations due to the quirks of experimenters or their apparatus. (Indeed with complex scientific experiments it is a formidable task to get anything to work at all.)

But for any extraordinary claim to gain respectability, it has to be replicable by someone somewhere. A recent example of the failure to meet this requirement was the discrediting of the exciting empirical claim by Pons and Fleischmann about so-called cold fusion.

The problem with psi phenomena is not that it is difficult for careful researchers to get it to work occasionally under rigorously controlled conditions; it is difficult for careful observers to get anything at all that can’t be dismissed as noise, error, wishful thinking, chance and often, sadly, fraud. It is for this reason that the requirements of controlled experiments and repeatability cannot be dismissed as unduly fussy: experience shows that nature does not cheat and that people sometimes do.

There are number of manipulative techniques such as “cold reading”, which are well known to psychics (and magicians), which are used to fool people into believing that there are special psychic powers.

Skepticism should not be confused with cynicism, though it frequently is. A cynic is someone who is inclined to believe the worst about people. Cynicism is however a form of skepticism: it is skepticism about the sincerity or goodness of human motives and actions. Historically, Cynics were a sect founded by Antisthenes, a pupil of Socrates, who condemned wealth and the enjoyments of life. The most extreme and celebrated exponent of the movement was Diogenes.

In the history of philosophy we find skeptical arguments are repeatedly proposed and then attacked and “refuted”. Skepticism is a continuing challenge to dogmatic claims, and helps to maintain the spirit of free inquiry. Without skepticism we would be in danger of failing to distinguish enthusiasm, prejudice and superstition from serious, rational, and well-grounded beliefs, which is essential to the task of making sense of the world.

Perhaps the main danger for skeptics is that they sometimes have difficulty in distinguishing hard and soft data, that they set their standards of epistemic acceptability at too high a level (in contrast to credulists, whose epistemic standards are too low) and may tend to promote their own form of dogmatic conservatism.

The aim of skepticism is to combat doctrinal rigidities which can afflict almost any belief system, but skeptics must remain alert to the possibility of falling prey to rigidities of their own. Skepticism is all about matching belief to evidence. It is a difficult and continuing challenge to maintain the right proportion of skepticism in our inquiries. Only then are we able to steer between the Scylla of dogmatism and the Charybdis of credulism.

Monkeying with Your Private Parts.

Rejuvenation! The wish of many a tired old man, and not so old: to regain the physical and sexual vigour of youth.

During the early decades of this century it was widely though not universally believed that such a rejuvenation, a turning back of the clock, could be achieved. It was thought that the secret of youth lay in the primary sex organs, so transplantation of the testis from young to old was the method adopted. In the 1920s a dozen or more surgeons around the world were ministering to this fervent desire by grafting the testes of young animals into those patients who could afford the fee.

We now know that this operation was quite useless, yet the surgeons and their hundreds of patients were on the whole convinced that the latter were indeed made to feel younger and fitter. Since that time we have discovered what formidable barriers the body raises against the introduction into it of “non-self” tissues. Material even from close relatives is rejected, and only in very recent times have methods been found for breaching the body’s defences to allow the intrusion of carefully matched foreign organs. This type of operation still makes newspaper headlines. Grafting between different species, using the techniques of sixty or more years ago, is impossible; rejection, the complete killing of the graft, would have been very rapid.

We have here, then, a most powerful example of the placebo effect, so a closer look at these events would follow naturally on Bill Morris’s article on the subject in the previous issue (Skeptic 27).

To set the scene, the medical background to the activities of the gland grafters, we note that as the century began the science of endocrinology was just beginning. The powerfully acting secretions of the endocrine glands were slowly being discovered and studied. First, the effect of extracts of thyroid glands on cretinism and myxoedema, then in the early twenties the anti-diabetic action of the pancreas extract insulin.

Gland Extracts to Restore Virility

It seemed a natural extension that an extract of the testis gland should restore flagging virility, and some unsuccessful trials along these lines took place. (when a hormone was, many years later, isolated from testes, and named testosterone. it was found not to have the effect sought.)

Seeking a more successful way of using the sex gland, surgeons looked to grafting. It was known at that time that cornea and bone could be transplanted from one person to another; it was not then realised that these successful grafts were rare exceptions — rather they were taken to indicate that grafts between people of any organ were possible. This view was strengthened when the discovery of blood groups enabled doctors to avoid the disasters which attended many of the early attempts at blood transfusion. The fact that some skin grafts did not “take” was ascribed to less-than-perfect technique, and many apparent “takes” were only the growth of the recipient’s own skin, and not the graft at all.

So the grafters got to work, initially on animals, and then on human patients. The usual technique was to excise the testis from the donor animal, open the scrotum of the recipient, and to place either the whole donor testis, or a slice, close up against one of the recipient’s testes, and then to sew him up again. In most cases the implanted tissue appeared to persist over time, giving the impression that the graft had “taken”. From our present standpoint we view this effect as the result of the rapid invasion of the graft by host cells, so the apparent “extra” gland was merely inactive host tissue.

Some of the earliest transplants into humans (1919 on) were carried out on those well-known experimental subjects, the residents of US gaols. These were man-to-man transplants, the “death row” of the prison serving as a regular source of fresh donor material. Dr Leo Stanley, chief Medico at San Quentin Prison in California, was the leader in this work, and carried out many transplants into “volunteer” prisoners during the 1920s. He and his patients were generally pleased with the results, and he impressed his fellow physicians sufficiently that several of them underwent the operation themselves.

In spite of this, there is no doubt that the most famous of the testis grafters was Serge Voronoff, a Russian émigré doctor of great wealth and charisma, active in Paris from the 1880s until the Second World War. Already in his 50s, and with a successful and fashionable medical career behind him, he turned in 1919 to the work that made him famous, his rejuvenation treatment. Lacking access to human material, he chose as donor animal the chimpanzee.

Believing that human grafts were possible, he picked on man’s closest relative as being the most likely to provide a transplant acceptable to the recipient’s tissues. Despite the expense (the chimpanzees alone cost a small fortune, as they each had to be caught in Africa and brought safely to France), he had many patients.

Voronoff’s fame during the 1920s arose not only from the “success” of his grafts, but also from his copious output of books on the subject, which he continued to publish long after the operation had passed out of favour. He had had from the outset critics who doubted the efficacy of the testis grafts, but it is uncertain whether, judged by the knowledge of the time, they had more reason for their skepticism than Voronoff had for his optimism.

The two British doctors’ journals took differing views: the Lancet was consistently critical of Voronoff’s medical claims and reviewed his books unfavourably, while the British Medical Journal was generally more approving.

Perhaps surprisingly, Voronoff’s undoing came not from a medical but a veterinary quarter. Emboldened by his success with human patients, he returned to his earlier interest in animals, and put his talents at the service of French agriculture. In 1924 he secured the use of a flock of sheep at an agricultural station deep in the French colony of Algeria. Some of the young rams of this flock received a testis graft, others were left unoperated. On reaching maturity, the operated rams were found to be heavier, and yielded more wool, than the unoperated controls. Not only this, but the progeny of the grafted rams also gave more wool.


Conclusive proof! Surely this evidence would silence those who had doubted. The animal results could be assessed objectively, unlike the confidential and subjective observations on the human patients. So groups of veterinarians and agriculturalists were invited to inspect the “super sheep.” All but one of the international visiting parties were quite convinced; only the British put their fingers on the fatal flaw in Voronoff’s case.

Translated into present-day statisticians’ jargon, he had failed to randomise his young rams at the start of the trial. It is as if we judged the winner of a race by noting who first crosses the finish line, without ensuring that all competitors started from the same place at the same time.

Knowing now that these grafts must have been rejected, we can only conclude that Voronoff had, perhaps unconsciously, selected the better quality rams for the transplant group, and that this superiority had carried on into the animals’ maturity, and to their offspring.

Voronoff’s claims for the superiority of the offspring of his grafted rams implied “inheritance of acquired characteristics;” thus, all unwittingly, he had strayed onto the battlefield between the Lamarckians and the Darwinians. So, by his sheep experiments, he widened the area of interest in his work beyond the medical, attracting the attention of veterinarians, agriculturalists and finally general biologists.

By 1930 medical opinion was already turning against him; the scrutiny of the non-medical scientists hastened this process. By their nature, his human operations were very private, confidential affairs, the results of which were quite inaccessible for objective assessment by others.

When the fad for this operation died down, and its uselessness was realised, the practitioners were widely ridiculed, and reviled as quacks and charlatans. This was incorrect and sadly ungenerous; with few exceptions these surgeons were sincere men who wholeheartedly believed in what they were doing. Voronoff himself defended his work until his death in 1951.

A Change of Glands

That is not quite the end of the story of the gland-grafters. At the same time as testis transplants were going out of fashion, as described above, endocrinology was discovering more and more hormones produced by the body’s many glands, and these were available for “treating” a wide range of disorders.

The pituitary gland, in particular, was found to have a special role in controlling the activity of other glands (it was at one time called “the conductor of the hormonic orchestra”). Injection of cells of the pituitary, then, could be used by unscrupulous doctors to treat whatever glandular deficiency the patient could be persuaded he had.

The leading practitioner, Dr Niehans, a Swiss, was active until the 1950s, and counted Top People (from Hollywood to the Vatican) among his patients. None of his injections could have been of any use.

What lessons ought we to learn from this story, this false turning in medical science? Firstly, we see that misguided enthusiasts can be as dangerous as unscrupulous quacks. Furthermore, we should all subject our enthusiasms to rigorous self-scrutiny.

If Voronoff had kept better records of his operations, and taken a more objective view of the results, he might eventually have seen his error. Had he invited a histologist to examine his early sheep grafts he might have been convinced that they had indeed been rejected by the host. From the patient’s viewpoint, a person unhappy with his present state of health, having undergone a very expensive and uncomfortable operation, carried out by a charming, confident and persuasive surgeon, can almost be guaranteed to confirm whatever outcome of the operation the surgeon suggests to him.

A last thought: in a period which delivered to women the suffrage, protective labour laws and power-driven domestic appliances, the “rejuvenation” movement was almost entirely male-oriented. No-one seems to have considered whether anything could be done to help the post-menopausal woman who longed to be twenty again.

I am indebted for the information in this article to The Monkey Gland Affair by David Hamilton, London: Chatto & Windus, 1986.

Put a Pixie in Your Petrol

A Sprite in your Spirit, a Bogle in your Benzine, a Fury in your Fuel, a Greyhound in your Gasoline. With acknowledgement to the oil company which, many years ago, urged us to “Put a Tiger in your Tank.”

“It is far too easy for promoters of such products to make extravagant claims, and very difficult, time consuming and expensive to challenge such claims … there needs to be a system whereby advertisers can be required to prove such fulsome claims, rather than requiring disbelievers to disprove such claims.”

Yet another moan about homeopathic medicines from the pages of Skeptical Inquirer? Wrong! The quotation above is from the New Zealand Automobile Association’s Directions (September 1992), and refers to “Petrol Pills,” claimed by the distributors to improve your car’s fuel consumption by up to 17%, increase power by 8-12%, and to reduce harmful emissions. In careful tests, the AA could not confirm any of these claims.

The “Petrol Pills” promotion was backed by the usual “unsolicited testimonials” and by vague test reports of doubtful provenance. The subject of this next note has an apparently more respectable origin. It was observed by a contributor to Skeptiker, our German counterpart, at a well-respected technical exhibition, “Ceramitec,” in Munich.

Among the many well-attested marvels of modern ceramic technology was the stand of a Japanese firm, introducing “Mixrax” pellets — a “philosopher’s stone,” according to our German colleagues. A few pellets in your petrol tank will alter the molecular structure of the fuel (!), so that the specific heat of combustion is raised. This is claimed to allow fuel savings of 10-20%, power increases of 10-20%, the reduction of CO2 and hydrocarbon emissions by 30-40%, and a general cleaning of motor and exhaust systems. This material of paranormal power is made by sintering together over twenty common ceramic materials. One of these contains uranium, and the “Mirax” pellets contain much more radioactivity than is usually considered safe. Apart from the safety aspect, automotive engineers can see no way in which these pellets could work as claimed.

Our final “pixies” do not actually go into the tank; they are magnets which are fastened round the fuel intake to the carburetor. They are claimed to “excite” the fuel as it passes to the engine, making it burn more efficiently and less pollutingly. New Scientist has reported on a number of these devices recently. The British Advertising Standards Authority has ruled against the claims made for several, on the ground that no evidence was provided to substantiate them. More colourfully, a university engineer says a dead chicken wrapped around the pipe would be just as effective. American authorities, both state and federal, have used the courts to stop the sale of these devices until the claims are proved.

A joke from my boyhood was about a man who installed so many petrol- saving devices in his car that his fuel savings exceeded 100%, and he had to stop occasionally to empty his overflowing tank. Apparently the old chestnut has not lost its point.

Acupuncture Exchange

In the medical magazine Patient Management, Denis Dutton last year presented a tongue-in-cheek account of how GPs might incorporate alternative techniques into their practices. The article generated an interesting exchange.

Dr Denis Dutton’s original article in the March edition (“Increasing Your Income While Appeasing Your Patients”, pp. 9-11), and his more recent reply to Dr Campbell’s letter in the June edition (“One rule for Orthodoxy, Another for the Rest of Us”, p. 7) raise several interesting issues.

Our society comprises Western-trained doctors who study and practise acupuncture. For many of us, enthusiasm was first sparked by noticing the beneficial effects of acupuncture in the clinical setting. Most of our members are experienced clinicians and in their opinion, the effects of acupuncture amount to more than the sum of willing, motivated doctors enhancing a placebo response.

Many have been motivated to study the philosophies and pathophysiology of Eastern medicine, in particular traditional Chinese medicine. The collection of clinical material has been meticulously recorded by the Chinese for centuries, but it is only in the last 15 years that textbooks have been available to us, showing the logic and complexity of this study of medicine.

The marriage of Eastern and Western medicines is an exciting and vital factor in many parts of the world. The double-blind crossover trial, which all doctors would agree has been a cornerstone for the development of safe, effective Western medicine, is, however, an inappropriate measure of acupuncture. The reasond for this become obvious when Western doctors study the basics of acupuncture. The observations of the Chinese seem to fit in with modern advances in biophysics and it is ultimately the advancement of these basic sciences which will make the who subject more understandable to non- clinicians like Denis Dutton.

By reacting to acupuncture and claiming Chinese medicine is based on primitive and fanciful concepts, the American NCAHF exposes itself as being either unaware of the complexities of the subject, or worse still, threatened by them.

The medical profession, if it is to continue to earn the respect of the public, should study both Western and Eastern medicine with open minds.

Only then can valued judgements be made.

Dr Robin Kelly, President, Medical Acupunture Society (NZ)

Dr Dutton’s Reply

According to Dr Kelly, modern advances in biophysics will make acupuncture finally understandable to stubbornly sceptical non- clinicians like me. Wrong: the mechanism of the treatment is not the issue. I don’t know how Panadeine works, but I accept that it does. It is not the failure of acupuncture’s supporters to demonstrate an intelligible mechanism that is in question, but the straightforward clinical claims made on its behalf. The history of medicine is littered with episodes of “willing, motivated doctors enhancing a placebo response”. There need be nothing the least bit stupid or venal about this; in their eagerness to help their patients, an intelligent doctor can develop a sincere faith in an ineffective treatment modality. Blind testing routines are our best defence agaist this possibility.

On the subject of mechanism, it is worth remarking that I am aware of two local medical practitioners who were trained in acupuncture (one in Beijing, the other in Auckland) and who have used it extensively. Becoming increasingly suspicious, both of these practitioners had the idea of intentionally placing their needles at the wrong points, according to the Chinese charts (which don’t all agree with one another, incidentally). They found no difference in the perceived effect. One of these doctors has stopped using acupuncture, and the other continues to use it in the opinion that it is the time and attention he is giving the patient that produces the benefit, rather than a psychological effect of turning the patient into a pin-cushion.

Claim and counter-claim about the clinical effectiveness of acupuncture is all fair enough, and I hope doctors interested in these issues will consult both sides of the debate [start with P. Skrabanek, Lancet 1: 1169-1171, 1984; Irish Med J 79(12): 334-335, 1986]. What I find deeply disturbing is that Dr Kelly would claim that blind trials, though they are a cornerstone of safe, effective Western medicine, are “an inappropriate measure of acupuncture”.

This is a claim frequently made on behalf of alternative treatments and I believe it should be regarded with the utmost contempt. When a patient asks about the symptoms that might be alleviated by acupuncture, a definite answer is forthcoming; no one ever says “Oh, we have no idea what symptoms acupuncture is good for”. When the patient asks how much it costs, again a definite answer is immediately ascertainable. But in the present case, when we further ask if the modality has been shown through blind testing to be clinically effective, we’re told by the President of the Medical Acupuncture Society of New Zealand that this would be inappropriate. Not that it hasn’t been done, or that the results have been in his view indecisive, but that it would be inappropriate. Why? His society’s members deem acupuncture appropriate for the patient’s symptoms, which are demonstrably real. Real money is deemed appropriate for the demonstrably real account the doctor sends out. Why shouldn’t the paying patient demand that her treatment be just as real, as demonstrated by scientific tests? How can anything else be “appropriate” except the magic question: is acupuncture clinically effective beyond the usual placebo responses?

The “exciting and vital” marriage Dr Kelly describes looks to me like one in which Western medicine has taken Eastern superstition as a mail-order bride.

Dr Denis Dutton, School of Fine Arts, University of Canterbury

Psychics’ Predictions Fizzle for 1992

President Bush was not re-elected. Madonna did not become a gospel singer, and a UFO base was not found in the Mexican desert. These were just a few of the many predictions that had been made for 1992 by famous “psychics”, but were dead wrong, as chronicled by the Bay Area Skeptics.

At the end of each year, many well-known “psychics” issue predictions for the year to come. Twelve months later, they issue another set of predictions, conveniently forgetting those made the year before, which are always nearly 100% wrong. Each year, however, the Bay Area Skeptics dig up the predictions made the year before, to the embarrassment of those who made them.

Many of the “psychic” predictions made are so vague that it is impossible to say if they came true or not: for example, Jeane Dixon’s prediction that Tracey Gold “faces perilous periods in July and October” [The Star, April 14, 1992] is not obviously true or false. Many other “predictions” involve things that happen every year, or else are not difficult to guess, such as terrorist incidents, marital strife for Charles and Diana, or severe winter storms. Many supposed “predictions” simply state that ongoing events and trends will continue, such as economic uncertainty, or conflict in the Middle East. Some predictions did of course come true, especially those that were unspecific, or not at all difficult to guess: several “psychics” correctly predicted that a hurricane would cause major destruction in Florida or Cuba, but not one was specific as to the date or principal location of the damage. Hurricanes occur, of course, every season in the Caribbean. Significantly, not one prediction which was both specific and surprising came true.

Other supposed “predictions” are not really predictions at all, but are actually disclosures of little-known events which are already under way, such as movie productions, marriage plans, business ventures, or developing scandals. Because questionable claims of having made an amazing prediction are frequently made in the wake of major news stories, the Bay Area Skeptics only evaluates predictions that were published or broadcast before the events they claimed to foretell.

New York “psychic” Lou Wright predicted that three men would unsuccessfully attempt to kidnap Candice Bergen in Paris, and Marlon Brando would be arrested for trying to bust his son out of jail [National Enquirer, Jan. 2, 1992].

Los Angeles “psychic” Maria Graciette predicted that a secret UFO base would be found deep in the Mexican desert, thousands of years old, and that Vice-President Dan Quayle, attending a World Series game, would impulsively interfere with a play [National Enquirer, June 9, 1992].

New York “psychic” John Monti predicted that “a massive hurricane will devastate Cuba and topple Castro’s regime,” that a huge AIDS epidemic would “threaten to end professional sports” [National Enquirer, Jan. 2, 1992], and that a scientific advance would allow women to delay menopause, allowing them to have children into their 60s [National Enquirer, June 9, 1992].

The famous Washington, D. C. “psychic” Jeane Dixon, who supposedly has a “gift of prophecy”, saw that Fidel Castro would be overthrown, possibly resulting in Cuba becoming part of the U. S., and Virginia governor Douglas Wilder would gain enough support for a “vice-presidential invitation”. President-elect Bill Clinton, however, she described as “the Democratic shooting star,” for whom “an organization of women will try to block his path” [The Star, Jan. 21, 1992]. President Bush’s ratings would climb, resulting in his re-election [The Star, July 7, 1992]. She also predicted “a promising economic upturn in the spring,” and that “broccoli will become the miracle vegetable of the ’90s” [The Star, Jan. 21, 1992].

Chicago “psychic” Irene Hughes predicted that Vanna White and her husband would purchase a “haunted” mansion in Beverly Hills, from which they would flee in terror a week later. Madonna’s career would be interrupted by a “mystery illness,” but she would recover after having a religious vision, and become a gospel singer [National Enquirer, June 9, 1992].

New York “psychic” Laura Steele predicted that an earthquake would topple the Gateway Arch in St. Louis, and that William Kennedy Smith would enter the priesthood to become a missionary in Africa [National Enquirer, Jan. 2, 1992].

Los Angeles “psychic” Judy Hevenly predicted that George Bush would be re-elected “by a landslide,” that Madonna would be hit by a car while jogging in New York’s Central Park [National Enquirer, Jan. 2, 1992], and that Gennifer Flowers would join the cast of a popular daytime soap opera [National Enquirer, June 9, 1992].

Another Southern California “psychic,” Clarisa Bernhardt, who is claimed to make “uncanny earthquake predictions,” warned that scientists would be “shocked” in October when supposedly earthquake-proof Florida is hit by a trembler, only weeks after being hit by “the worst hurricane in the state’s history.” The prediction that this year’s hurricane season would produce Florida’s worst destruction yet was correct, but the earthquake prediction was dead wrong. Bernhardt also predicted that Joan Lunden would renew her marriage vows on her TV show, “Good Morning America” [National Enquirer, June 9, 1992], that Michael Jackson would lose his voice and quit singing, and that Joan Rivers would be plagued by three look-alikes created through “extensive plastic surgery” [National Enquirer, Jan. 2, 1992].

Joan Quigley of San Francisco, White House astrologer to the Reagans, predicted that Bill Clinton would run out of money toward the campaign’s end, and that the total eclipse of the sun on June 30 will cause earthshaking events in China [Washington Post, April 18, 1992].

Here in Northern California, the date of that devastating California earthquake everybody keeps predicting was pegged for Oct. 17, the third anniversary of the Loma Prieta quake, by “psychic” Ernesto A. Moshe Montgomery, who claims an accuracy of 99 1/2 percent [San Jose Metro, Feb. 27, 1992].

Based on the continuing failure of the “psychics” to make accurate predictions over the years, the Bay Area Skeptics urges everyone — especially the media — to exercise some healthy skepticism when “psychics” and other purveyors of the paranormal make extra-ordinary claims or predictions. Anyone who swallows the “psychics'” claims year after year without checking the record is setting a bad example for students and for the public.

It is important to note that no “psychic” succeeded in predicting the genuinely surprising news stories of 1992: The destructive fire in Windsor Castle; the feud between Vice-President Quayle and Murphy Brown; the surprising presidential campaign of Ross Perot. These major news stories were so totally unexpected that someone would have had to be genuinely “psychic” to have predicted them twelve months ago! Given the sheer number of so-called “psychics” out there, one would expect that if even one of them were genuine, these things would have been correctly predicted; and since they were not, it suggests that all such claims of “psychic powers” are without foundation.

“Mystical explanations are considered deep. The truth is that they are not even superficial.”
– Friedrich Nietzsche
(The Gay Science: 126)

Beware – This Tea Could Be Dangererous

Where’er you be
Don’t drink comfree
For drinking such tea
Could be the death of thee!

John R. L. Walker

Our everyday “cuppa” comes from the plant Camellia sinensis and it, together with a number of other common drinks including coffee, cocoa, guarana and maté contain small quantities (10-100 mg per cup) of caffeine, a mildly stimulatory alkaloid. In addition many people enjoy hot and cold beverages made from a wide variety of other herbs such as chamomile and dried raspberry leaves.

Unfortunately, an uncritical mythology has developed regarding herbal teas made from other plants that maybe very dangerous. Notable among these are herbal teas made from comfrey, coltsfoot and sassafras; the former contain toxic alkaloids while the latter contains the carcinogen safrole. Recently, the German government’s health authority, the Bundesgesundheitampt (BGA), has decided to ban some fifty herbal and homeopathic remedies because they are ineffective or contain toxic alkaloids. High on their list is comfrey.

They comment that although a medicament is derived from a common plant, it can be just as dangerous as any laboratory-synthesised chemical. This fact has been well known since the death of Socrates from a dose of hemlock (which contains the alkaloid coniine), but is all too often conveniently ignored by the herbal mystics.

Here in New Zealand there are many recorded animal deaths from ingestion of tutu (Coraria arborea) which contains “tutin”, a poisonous picrotoxinin.

Comfrey (Symphytum officinale) has aquired an almost magical status in herbal medicine, comparable almost to that of ginseng. It is one of the most often sold herbal remedies. However, unlike ginseng, comfrey has been shown to contain highly toxic alkaloids, yet many modern herbalists still wax lyrical about its safety and almost universal healing properties.

Comfrey is frequently used in folk medicine as an externally applied poultice for wound healing, and such treatments may be useful since comfrey contains allantoin, which promotes cell proliferation, tannins and mucilage.

So far so good, but comfrey is also recommended by many herbalists to be taken internally as a “blood purifier” and as a universal panacea for numerous other ailments including respiratory complaints and ulcers of the bowels, stomach, liver or gall bladder.

Now, in the light of much well-documented research, the German BGA has banned the sale of herbal remedies containing comfrey. This is because comfrey contains a group of chemicals known as the pyrrolizidine alkaloids which have been shown to be carcinogenic and to cause severe, even fatal, damage to the liver.

Coltsfoot (Tussilago farfara) and Senecio species, such as groundsel, are other common herbal remedies which also contain these dangerous pyrrolizidine alkaloids, although for many years coltsfoot has been prescribed as an ingredient of herbal cough syrups and smoking mixtures. Japanese and other research workers have shown that these preparations may be potential causes of liver damage.

Problems with herbal remedies nay also arise from other causes such as adulteration, contamination and misidentification. The latter should be of major concern since, for most herbal products, there is no guarantee that the original plant(s) were unequivocally identified by a competent botanist.

As with any drug, susceptibility to poisoning varies between individuals and may be affected by gender, age and state of health. in a recent paper Dr Ryan J. Huxtable comments that, in North America, more people are killed or injured by plant derived substances than by animals. Yet, despite this, the US herbal industry is still virtually unregulated and without legal safeguards to demonstrate the safety or efficacy of its products.

Locally sourced herbal teas from New Zealand native plants are now becoming available, but we should remember that many of our native plants produce alkaloids and other toxins which are dangerous if ingested. I therefore caution anyone who buys a herbal beverage to require not only a list of its plant components but also to be sure that these plants were competently identified.

For the edification of readers I append a list of a few common poisonous plants found in New Zealand and which I would not want in “my cup of tea”.

Common Poisonous Plants

Plant Botanical Name Toxic Principle
Apricot (kernals) Persea armeniaca Cyanogenic glycosides
Bittersweet Solanum dulcamara Alkaloids
Foxglove Digitalis purpurea Steroidal glycosides
Hellebore Helleborus sp Steroidal glycosides
Karaka (fruit) Cornyocarpus laevigatus Cyanogenic glycosides
Kowhai Sophora sp Alkaloids
Ngaio Myoporum laetum Ngaione
Peach (kernals) Prunus persica Cyanogenic glycosides
Porporo solanum aviculare steroidal glycoalkaloids
Ragworts Senecio sp Pyrrolizidine alkaloids
Tutu Coraria sp Tutin


Connor, H.E. The Poisonous Plants in New Zealand. (1977) Govt Printer, Wgtn.

Huxtable, R.J. (1992) The Myth of Benificent Natue; the risks of herbal preparations. Annals of Internal Medicine 117; 165-166.

Stewart, J. Plants in New Zealand Poisonous to Man. (1975) Govt Printer, Wgtn.

Tyler, V.E. The New Honest Herbal (1987) George F Stickley Co. Philadelphia. (Highly recommended).

The Placebo Effect

Many people will remember Dr Bill Morris’s entertaining autobiographical talk at the last Skeptics’ conference in Wellington. From his presentation, we extract this discussion of what is still the most persistent and potent medical effect known to the human race.

The word “placebo” may or may not be recognisable to you as being of Latin origin, from the verb placeo, placere, to please, and placebo is the first person singular of the future indicative tense, or “I shall please.” Its first recorded use in the English language was in 1225 in reference to Vespers in the Office for the Dead, and the word was derived from the first word of Psalm 116 v 9 “Placebo Domino in regione vivorum.” This is usually translated as “I shall walk before the lord in the land of the living,” but as the Vespers for the dead was in effect a request for the dead to intercede with God for the benefit of the living, it is better translated as “I shall please or intercede with God on behalf of those in the land of the living.”

By 1386 it had appeared in Chaucer’s Merchant’s Tale to mean a flatterer and by 1811 it had acquired one of its modern senses as “…an epithet given to a medicine adapted more to please than to benefit the patient.”

It may surprise you to learn that it was as late as 1938 before the word appeared in its other modern sense, that of a dummy medication used as a control, and probably the first well documented randomised placebo controlled trial was that of streptomycin for the treatment of tuberculosis of the lung, in 1948.

The Medical Research Council pointed out that the natural history of tuberculosis of the lung was so variable that “evidence of improvement or cure following the use of a new drug in a few cases cannot be accepted as proof of the effect of that drug” by contrast with tuberculous meningitis which was invariably fatal without treatment.

The placebo treatment was bed rest alone, whereas the streptomycin group received both bed rest and streptomycin. In this instance the patients obviously knew they were getting streptomycin as it has to be given by injection, but the progress of the disease was followed on chest X-rays which were assessed without knowledge of which treatment the patients had received.

Ethical considerations did not apply, as the only possible alternative treatment at that time was bed rest, and in any case only limited amounts of streptomycin were available. Nearly forty five years on, it is difficult to accept that bed rest alone was perceived to be an effective treatment.

By 1950 the Journal of Clinical Investigation wrote, “It is customary to control drug experiments on various clinical syndromes with placebos, especially when the data to be evaluated are chiefly subjective.” and so by this date, the use of dummy medication in drug trials was firmly established.

It soon became clear that many people reported side effects or improvement when receiving placebos in trials and it soon became possible, though perhaps not useful, to say that the placebo effect was that which all treatments have in common. Perhaps more useful is to combine the two definitions and say that it is a non-specific effect of a treatment attributable to it but not to its pharmacological properties.

Any form of treatment can act as a placebo, and the strength of the reaction varies with the supposed potency of the treatment so that a capsule is better than a tablet, an injection is better than a capsule, an injection that stings is better than one that doesn’t and an operation is even better than an injection that stings.

In 1939 it was suggested in Italy that tying off the internal mammary arteries could greatly reduce the pain of angina pectoritis. The operation eventually became fashionable in the USA with quite spectacular results. The patients said they felt better and there was objective evidence to support this in that they could walk further and their consumption of angina pills decreased.

Eventually a double blind controlled study was done in which half the patients had their internal mammary arteries tied and the other half simply had them exposed without tying them. Neither the patients nor those who assessed them knew until the study was completed who belonged to which group. It turned out that ligation had no greater effect than the dummy operation. Since ligation of the internal mammary arteries was quite a major operation with potential for harm as well as good, and there was genuine doubt that it was useful, not only was the trial ethical, but it would have been unethical not to have done it.

Placebos can also cause toxic effects just like those of an active drug, and in a study of 25 patients given placebos, ten reported sleepiness, nine palpitations, eight irritability, five weakness with a fall in blood pressure of more than 20 mm of mercury, four reported diarrhoea, two collapse and two itching. Three of the patients also developed dependence on the placebo (lactose) and had withdrawal symptoms when it was stopped.

Now one suspects that if we stopped people in the street at random they might report a similar rate of these symptoms, and at the 1992 Skeptics Conference, on asking for a show of hands, I found that the proportions enjoying the symptoms listed above were greatly exceeded.

As soon as the placebo effect became clear, investigators began to look for factors which might identify the placebo responder in the hope that eliminating them from the studies would make the data much clearer.

A variety of psychological studies has been done but there are so many inconsistencies among the results that one can conclude that there is no single personality trait that characterises the positive placebo reactor, with the possible exception that stress or anxiety has been rather consistently associated with placebo reactivity. Expectation has been cited as a possible mechanism.

In one study, experimenters were told that their rats had been bred especially either for intelligence or dullness, although in fact all the rats were from the same genetic strain. The experimenters then performed learning experiments on the rats and obtained results that conformed to their expectation.

Brody cites this as possible support for the idea that if experimenters can somehow communicate their expectations of the rats’ behaviour to the rats “It seems reasonable to assume that physicians can unknowingly communicate their expectations and attitudes to the patients, altering the patients’ therapeutic outcomes as a result.” My own view is that old Procrustes is at it again, altering the accuracy of the experimenters’ observations rather than the rats’ behaviour.

Theories of placebo action have been largely psychological or psychoanalytical, but a reductionist like myself sees behaviour, feelings, thoughts and so on in terms of as yet poorly understood physico-chemical activities in the brain and peripheral nervous system, rather than as something happening somewhere in a bubble marked “psyche.” A little support for this view comes from a randomised double blind placebo controlled study by Levine and others into the mechanism of pain relief following extraction of impacted lower wisdom teeth. A third were given naloxone, a substance which is believed to inhibit the action of naturally occurring pain relieving substances in the brain called endorphins, a third were given a placebo and a third were given morphine. Those given naloxone reported significantly more pain than those given the placebo.

Levine hypothesised on this basis that placebo pain relief is mediated by endorphin release, but as Skrabanek pointed out later, they did not test their hypothesis by actually measuring endorphin levels, and in any case the results were exactly what might be expected if the naloxone were acting as a placebo itself. The paper was also severely criticised by Korczyn, but nevertheless it continues to be quoted quite extensively as “demonstrating” that pain relief by placebos is mediated by endorphins, a claim, incidentally, that is also made for pain relief by acupuncture.

We simply do not know why about thirty percent of patients experience relief of symptoms when given a therapy that cannot be expected to have any effect. In a sense, the history of medicine up to about 1950 is largely the history of placebos. We may find it amusing to look at some of the truths of yesterday which are the falsehoods of today, like the fashion for enemata in eighteenth and nineteenth century France. Sometimes enemata even of tobacco smoke were administered, and while we cannot feel entirely confident that the Tobacco Institute would disapprove of this, we can feel sure that many of our present day medical practices will appear stupid and ignorant to our great grand-children.

For the last forty five years we have had the means to set a limit to our errors, and yet colleagues tend to set store by anecdotes and case series which are in truth little better than a succession of anecdotes. The results of poorly designed case control studies continue to be accepted without proper caution. If physics is the queen of the sciences, then the randomised double blind placebo controlled study is the queen of medical investigation, though for events that occur relatively rarely, cohort studies and case control studies are inevitable second and third best choices.

People, including I am sad to say, doctors, have said to me “What does it matter whether a treatment is a placebo or not as long as it works? Surely the thing is to cure the patient and when you cannot cure, to comfort.” I can certainly agree with the aim, but not that it does not matter how we do it. If we do not make sure of the truth then we shall not be able to separate the wheat of science from the chaff of falsehood, and as Berthold Brecht put it, the aim of science is not to open a door to infinite wisdom, but to set a limit to infinite error.

UFO Update

Dr J.F. De Bock gave the 1992 Conference an update on the study of UFOs.<>

The study of UFOs (UFOlogy) started out as research on unidentified atmospheric (or aerial) phenomena, but rapidly became invested with questionable researchers holding preoccupied, but popular, convictions that the earth is being invaded by extraterrestrials in their flying-saucer shaped spaceships.

The alleged recovery of aliens and their saucer in the 1947 Roswell Incident, and the photos of a hovering spaceship in the 1981 Gulf Breeze case, fuel the belief in extraterrestrial visitation. However, both cases are so invested with fraud, swindle, deception and contradiction that arriving at the truth is seemingly an impossible task.

To further cloud the credibility of serious UFO researchers, UFOlogy is forced to absorb subjects such as contactees, crop circles, Men in Black and cattle mutilations.

“True” UFOlogy is a continued unbiased research into verified sightings and encounters of mostly unidentified lights, occasionally exhibiting a physical reality by leaving a variety of tangible proof of exchange with the environment.

In 1989, during a UFO chase by two Belgian Fl6 fighters, the elusive unidentified object demonstrated seemingly controlled and deliberately evasive action, momentarily appearing to swing the balance in favour of the belief in alien visitation. Unfortunately, one finds that the case was reported by dubious researchers being too over-zealous to promote the extraterrestrial hypothesis. When the dust dies down, one is left with a confirmed sighting of a repetitive and common but puzzling occurrence of an unknown atmospheric phenomenon.

How to Make the Miraculous Blood of St Januarius

Brew up a miracle for fun and profit, in the comfort of your own kitchen.

The blood, in a phial in a church in Naples, is reverently turned over several times during services every few months. It has seldom failed to liquefy since 1389. (It has also accidentally liquefied when the monstrance holding the phial was being cleaned!) Three Italian scientists are quoted in the Skeptical Inquirer (Vol 16, No 3, Spring 1992, p236) as having duplicated the “blood.” The relevant data (Nature vol 353, p507) are:

“To a solution of 25g FeCl3.6H2O in 100 ml of water we slowly added 10g CaCO3, and dialysed this solution for 4 days against distilled water from a Spectra/por tubing (parchment or animal gut works just as well; a simple procedure1 even allows us to avoid this dialysis step). The resulting solution was allowed to evaporate from a crystallisation disc to a volume of 100ml (containing about 7.5% of FeO(OH). Addition of 1.7g NaCl yielded dark brownish thixotropic sol which set in about 1 hour to a gel. The gel could be easily liquefied by gentle shaking, and the liquefaction-solidification cycle was highly repeatable.”

Thixotropy is the property that interests us, that of setting to a gel or shaking to a sol(ution). I had always imagined the warmth of the priest’s hands was the main secular reason for the liquefaction, but apparently not.

I rang my old chemistry master, Alex Wooff, in Christchurch, to find out what the dialysis would involve. Dialysis is a differential diffusion through a membrane. You put the mix in a tube (rather like a sausage skin with the ends tied, I gather) and the tube in a tank of distilled water. Certain acidic by-products pass out through the tube walls, and what you want stays inside. (Someone who speaks French could look up what Herr Doktor Guthknecht had to say in 1946 about avoiding that.)

Alan Wooff also explained that the calcium carbonate would have to be precipitated — common chalk wouldn’t do; “You wouldn’t want lumps in it.”

Perhaps (I like to give people the benefit of every possible doubt) the 14th century originators of this pious fraud did not use sausage skin — let alone Spectra/por tubing — but stripped a blood-filled vein from the saint’s leg, say, and piously washed it in a mountain stream, like kaanga pirau.

If some reaction turned the iron in the haemoglobin into FeO(OH)– a reaction with the chalky deposits of the saintly artherosclerosis, perhaps? — and all unknowing they dialysed it out, perhaps they would get the result that the faithful see in Naples to this day.


Denise of Salmond Smith Biolab (Freephone 0800-807-809) told me they could get precipitated calcium carbonate (CaCO3) from England for $22.86 a kilo, in six or eight weeks by air freight at $39. They have hydrous ferric chloride (FeCl3.6H2O) in stock at $47.22 for 250 grams. The minimum order of dialysis tubing (10mm diam, 32mm flat) is 30 metres at $60. Geoff Meadows of Clark Products Ltd quoted $36.59 for 20 l of deionised water.

The limiting dimension is the volume of the tubing, 2.35 litres. That divides into 78 samples of 30 ml each.

That’s $205.67 (plus the cost of the phials) to produce 78 phials of miraculous blood. Perhaps 20 skeptics might pay $10 each for them, so I’d be lucky to break even. That is, if all the kitchen chemistry worked out.

Of course, if I sold them outside a church at $1000 a phial…?

Anyone got access to a chemistry lab?

1. Guthknecht, R. Bull Soc. Chim. Fr. 13, 55-60 (1946)
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This is a summary of a talk given at the 1992 Skeptics conference by Dr Eric Geiringer.

[An E-meter is a device used by members of the Church of Scientology, and some related groups or individuals, to “diagnose” illnesses. The subject grasps a pair of metal electrodes connected to an Ohm-meter, and an “auditor” asks questions and interprets the meter’s readings.]

The resistance the skin offers to the passage of an electric current is inversely proportional to the amount of electrolyte in the neighbourhood, and that essentially means sodium chloride in the sweat.

The skin is an important regulator of the sodium chloride content of the tissues, which must remain constant within narrow limits.

The amount of sweat and its salt concentration (0.1-0.37%) will vary in different people and at different times in the same person with:

  • fluid intake
  • clothes
  • stage of menstrual cycle
  • amount of salt in the tissues
  • amount of salt in food
  • the circum-ambient temperature
  • the number of sweat glands
  • their topical distribution
  • adrenal activity
  • anterior pituitary activity
  • posterior pituitary activity
  • hormone output of heart muscle
  • kidney function

and a number of other factors, all playing a part at any given moment in determining how much salt will meet the electrodes.

To this must be added the psychic state of the subject at the time of measurement, because as with blushing (which is also part of the hypothalamic heat regulating mechanism) sweating will be brought on by joy, fear, embarrassment or pain.

The effect of these variables on the final reading is, of course, additive and gives a composite reading of little, if any, specific value.

E-meter operators may claim that the refinements which they have introduced into the machine and the method standardise subjects to all these variables, and can therefore isolate idiosyncratic differences and enable specific physical or mental disorders to be diagnosed, but it would be up to them to substantiate such an extraordinary claim.

Although Scientology in toto is a dangerous, exploitative and mischievous humbug, we must concede that, by recording and utilising psychic sweating to loaded questions, their use of the E-meter is on a par with the use of lie-detectors<|>–<|>i.e. a crude, nonspecific but marginally valid means of spotting emotionally sensitive areas in a significant number of subjects.

It is the imaginative use, or pretended use, of these Ohm-meters and Volt-meters to diagnose specific mental or physical disorders by homeopaths and acupuncturists which constitutes their real danger.

Hot-footing it in Fiji

New Zealand Skeptics walk happily on red-hot embers, protected by the laws of physics. Fijian firewalkers, however, are said to stroll across white-hot stones. How do they do it?

Fijian firewalking is an ancient tradition. It was originally confined to a few villages on the island of Beqa (pronounced Mbengga). The ceremony achieved fame with a demonstration for visiting European dignitaries in 1885.

As John Campbell explains in Skeptic 15, firewalking is explained by science, not mysticism. Although the firewalker’s skin is in contact with glowing carbon at a temperature of around 700oC, very little heat energy is transferred. No injury occurs because though the surface of the charcoal is at this temperature, the charcoal has a low heat capacity and heat is not conducted through it sufficiently rapidly to raise the skin temperature to a dangerous level. Each foot only contacts the hot charcoal twice for a brief instant. Of course, if skin and hot carbon were in contact for longer, or if the walker attempted to take too many steps on the hot coals, burns would ensue. Faith in one’s firewalking abilities has no effect on the outcome.

Beqa Firewalking

Several published accounts of the Beqa firewalkers describe a ceremony with features that cannot be accounted for by this explanation. Many of these descriptions are rather informal (as well as unbelievable). Others are by anthropologists interested in rituals and beliefs associated with the ceremony. These describe human behaviour in minute detail until it gets to the part which would most interest a physical scientist. Some writers seem unaware that they are describing events which are commonly thought impossible.

Accounts agree that flat stones or rocks are heated using wood fuel in a fire-pit. The wood is then raked away, leaving the stones glowing white-hot. After various rituals, the walkers enter the pit and walk round and round on the glowing stones. The men (only men can do this!) have anklets of dried leaves; afterwards neither these anklets nor the soles of their feet show any effect from the heat.

According to Beqa: Island of Firewalkers (published by the Institute of Pacific Studies), the men even gather in the centre of the pit and chant! If these accounts are reasonably accurate then we are dealing with a miracle.

Profit Potential

About 1960 the villagers of Rukua on Beqa discovered that firewalking had commercial potential. The income of this village jumped from about $400 per year to about $6500 with this discovery, and other villages quickly followed their example. Contracts with tourist hotels guaranteed $400 per performance.

The original ceremony had involved the whole village. Firewalkers had to respect certain tabu — in particular, abstinence from all sexual contact for a period of one month. Costumes were made and burned afterwards. About six tonnes of firewood were consumed.


It was quickly discovered that costumes could be modified so that they could be re-used and a much smaller fire satisfied the tourists. If the walkers abstained from sex for only two weeks they were not injured by the smaller fire — this seems quite logical.

More hotels featured the ceremony and teams performed twice a week. The sexual abstinence tabu was reduced to one night or dropped altogether.

Traditionally the fire pit was large. Beqa: Island of Firewalkers contains some photos from the thirties and I have an old postcard of the ceremony. These suggest the hot area was around five metres in diameter (the pits are circular) and the walkers may have needed ten or a dozen steps to cross the hot stones.

The modern pit is about 2.5 metres, but in the two examples I have seen, the hot area was less than two metres in diameter. Apparently the cost of firewood is a big problem.

I have a postcard showing the preparation of a fire pit for a modern performance. The caption reads, “the fire-walkers the cross the pit walking on the white-hot stones.”

Skeptics can safely walk on red-hot charcoal, but “white hot” implies much higher temperatures. For example, mild steel is tapped from a furnace at about 1600oC. This molten metal is glowing brightly but it looks yellow rather than white.

Rock, unlike carbon, has a high thermal capacity, that is, it stores plenty of heat energy which can be released to human skin. This implies that hot rock is more hostile to human feet than carbon at a similar temperature.

Anybody with some knowledge of science should be dubious of the published accounts of Beqa fire-walking. Could the rocks really be white hot?

The anklets worn by the walkers provide a clue. If dead leaves were brought close to an object radiating at a temperature high enough to be glowing white, they would burst into flames. In fact, human skin could be damaged before contact.

Examining the Pit

In Fiji, I have twice had a good look at a fire-pit immediately before the ceremony. When the fire was dying down, any unburnt wood was raked aside and the stones brushed clear of glowing embers. White ash covered the stones which lay in a bed of glowing charcoal. They were so close together that little of the hot charcoal could be seen, but the white sides of the irregular rocks reflected the glow in a spectacular fashion. The rocks themselves were not glowing.

Obviously, the rock upper surfaces were at a temperature well below the 700oC of glowing carbon. This could explain why the Beqa people can stand relatively prolonged contact. The modern walkers cross the pit, circle round the edge and re-cross. All the tourists I have questioned agree on that point. I am sure anybody could do the same.

The photographs I have of the old ceremony with the large pit do not show any activity that could be construed as “walking round and round in the pit.” The old postcard shows a line of about fifteen people, some holding hands. About four or five are crossing the hot rocks. The rest appear to have crossed and are circling back around the edge.

In the pit they seem to be taking short steps, and perhaps few people have feet that could stand such lengthy exposure. However, these people probably never wore any kind of footwear. Certainly some modern Fijians can stand barefoot on a sun-heated surface that would cause me pain.

On the other hand, it is doubtful that Beqa people could have crossed such a large pit, so slowly, if they had had to walk on glowing charcoal rather than the relatively cool rock.

So how did this myth arise, that Fijians could walk barefoot across white-hot rocks?

Poor observation and inaccurate reporting, plus the will to believe, seem adequate explanations. The rocks are certainly white as they are covered in white ash; they are certainly hot, as they are heated in a fire. They are not, however, white-hot.