Diluting the scientific method: Ars looks at homeopathy (again)

In honor of World Homeopathy Week, we discuss why it shouldn't be celebrated.

by John Timmer, Matt Ford, Chris Lee, and Jonathan Gitlin - Apr 13 2013, 8:15am EDT

• Science Policy and Education

http://arstechnica.com/science/2013/04/the-pseudoscience-behind-homeopathy/

Aurich Lawson

Over the past couple of weeks, Ars has started receiving e-mails about a topic that doesn't really fit into our normal areas of coverage: homeopathy. The belief that the administration of nothing more than water can have a medicinal affect certainly isn't technology, and it only peripherally touches upon science, in the sense that any health benefits it provides seem to involve the placebo affect.
Nevertheless, many of the practitioners of homeopathy have tried to claim the mantle of science, creating scientific-sounding explanations for "water memory"—the idea that a substance can actually gain potency as it is diluted out of existence. These practitioners even formed a peer-reviewed journal to discuss their findings. Six years ago, the journal Homeopathy ran a special issue on these explanations, and the Ars writers teamed up to tackle the bizarre distortions of science that it contained.
So in honor of World Homeopathy Week (which we just received a press release for), we're going to run an updated version of that story. Not because we think there's a value in talking about homeopathy. Rather, by scientifically evaluating homeopathy's attempts to sound scientific and revealing it to be nothing more than "pseudoscience," we think it's possible to learn something about the scientific process and the reasoning that drives it. In turn, we can possibly learn to recognize other areas where scientific reasoning has ended up on the rocks.
This feature was originally published on September 11, 2007.

Welcome to Waterworld

Science can be a tricky thing to define, and it's sometimes easier to contrast it with some of the arguments that pose as science. Unfortunately, most of those issues are entangled with implications that keep the basic question—is this science?—obscured by emotional responses. Thus, the science of climatology has become entwined with political, economic, and policy issues. The science of evolution conflicts with the political and religious goals of some individuals. Even basic scientific questions about the nervous system get embroiled in family and personal health issues when topics like autism and radio frequency radiation are broached.
That's why a special edition of the journal Homeopathy appears to be a gift, allowing us to look at science and pseudoscience without getting entangled with politics and religion. Homeopathy claims to be a form of medical practice that's based on the principle that "like cures like." Given a set of symptoms, a homeopath will identify an herb or chemical that causes similar symptoms. Following a predefined ritual, the homeopath performs a series of dilutions of that chemical that continue well beyond the point where there should be no molecules of it left—the final solution is essentially well-shaken water.
Giving patients water is probably a lot less harmful than many folk remedies that fly under the scientific radar, but homeopathy has two notable distinctions. One is that people spend a lot of money on it—the US market was already close to half a billion dollars in 1999. The second is that homeopaths have demanded that their field be treated as a science, performing clinical studies, proposing mechanisms, and even convincing Elsevier to publish Homeopathy, a peer-reviewed journal.
The articles in this special edition of Homeopathy display a number of consistent themes: internal inconsistency, a rejection of scientific standards and methods, and established science being applied to inappropriate situations (for example, quantum entanglement between people is proposed). In cases where mechanisms are suggested, they frequently violate our basic understanding of the natural world. Tying things together are unsupported assertions and logical leaps that have no place in science. The experience of reading the journal was like seeing a science publication reflected through Alice's looking-glass.
By criticizing homeopathy, we hope to illuminate the general distinctions between science and pseudoscience. Hopefully, in finding a topic that's largely free of baggage, we'll help provide a broader picture of what makes science distinct from fields that feign scientific legitimacy.

Suppression of water memory

Most special editions start with an editor's comment; this is no exception. Homeopathy’s editor acknowledges that the most widely held theory for homeopathic action involves the placebo effect. However, he also claims that there is a growing body of evidence for the efficacy of homeopathy, so water memory should be investigated further. He makes a bold claim regarding what the results will be: "There is much work to be done, but at this stage we can say one thing with certainty: the assertion that homeopathy is impossible because the 'memory of water' is impossible is wrong."

The memory of water.

Does the rest of this issue bear out this statement? The second article, entitled "The memory of water: an overview,” acts as an introduction. The implication of this title is that we should be able to get a good feel for the state of the field, where it is heading, and what challenges remain.
The author, Martin F. Chaplin, writes with the assumption that the existence of water memory is obvious. But Chaplin never gives a definition of the "water memory effect." As one reads the article, it becomes clear that any behavior of water that is non-obvious is "water memory." This allows Chaplin to present a mix of trivia as if it formed a coherent body of scientific evidence. Oddly, whenever any of these behaviors must be described, Chaplin presents an analogy. We have never seen analogy used in scientific writing as a replacement for a direct, formal argument.
It would seem to be possible to demonstrate the role of water memory in homeopathy in two ways: physical measurement of some structure that was imposed upon water by the active ingredient or by the demonstrated efficacy of the diluted solution. Chaplin apparently disagrees. In fact, he appears to overtly plead for homeopathy to be held to a non-scientific standard:
"Editorial comment in the scientific press has subsequently drawn on whether water can indeed show any 'memory' of its prior history as direct 'proof' of whether homeopathy can be successful or not. Such linkage is quite unnecessary and may easily mislead as the two areas use fundamentally differing and entirely independent evidence and should therefore be considered separately."
In a certain sense this is true; consistent observations for the efficacy of homeopathy can and would stand alone. However, no such body of evidence appears in this issue, which shifts the burden back to evidence for the memory of water.
Water memory claims violate several deeply studied physical principles that are backed by a great deal of evidence, so proof of the failure of these principles should require solid data. Instead, we are subjected to increasingly wild and far-fetched proposals that, in the absence of direct evidence, must be investigated as a substitute. Chaplin bristles at the fact that these proposals have not been well received by the scientific community, and he suggests that science’s high standards for overturning established principles have "resulted in the slow uptake of new ideas and the overly long retention of fallacious concepts."
Let's consider science's track record in this regard. Quantum mechanics, special relativity, and general relativity spring to mind as examples of radical new ideas. They went from new hypotheses to accepted theories in less than the working lifetime of the scientists involved. RNA splicing and interference were radical at the time, yet they were quickly accepted on the basis of solid evidence. This should tell you something about both science and the article's author.

Water's selective memory

Water supposedly only remembers what a homeopath wants it to.

Chaplin also addresses a key question: if water can retain a memory of a vanished substance, why isn't all water pharmaceutically active? After all, water comes across a huge variety of substances as it cycles through the ecosystem.
He responds: "I do not dispute this argument, but it is of no relevance to the state of known samples of liquid water, where the history concerns just the sample and is not the sum of the individual memories of all the molecules since the beginning of time (indeed individual H₂O molecules only have lifetimes of fractions of a second)." This would imply that water only remembers the limited history that is known by the people who consider a sample of it.
Chaplin then moves away from memory and into structure. His claim is that the homeopath's ingredients structure the water, and that structure is somehow retained during dilution. One of the main references cited is a light scattering study on samples of water containing various chemical compounds, all of which aggregate into large-scale domains over the period of several hours, days, or even months. Sounds like evidence, right? Well, yes, except that the concentrations studied are between six and ten percent; this leaves a large gap between these studies and anything related to homeopathy.

The persistence of the memory of water

In the end, water memory and water structure, according to the evidence presented by Chaplin, are anything but self-evident. This seems to weigh on Chaplin's mind, but rather than strengthening his arguments, he simply proposes alternate ways in which homeopathy might work. He moves on to look at ways in which the active ingredient (or some other random stuff) might be in the final "medicinal product." These take the form of, for example: silica from the glass, residual material on the glass surface, and (our favorite) aerosol matter. "Although not often recognized, except by microbiologists, such shaking can also produce aerosols saturating the laboratory atmosphere for extended periods and offering a route for the contamination of later dilutions," he writes.
This is true, but one question to ask is this: did the homeopath wear gloves and a mask? Because if they didn't, that water probably contains more stuff from the homeopath’s breath than any active ingredient—not a confidence-inspiring thought. It is truly remarkable that Chaplin spends time discussing these possible explanations for water's memory, in part because they obviate the need for any of his prior explanations.
In the end, this overview provides a clear demonstration of tactics used by many practitioners of pseudoscience: make a large number of vaguely scientific arguments in the hope of making the desired conclusion seem inevitable. It is essential to recognize that a disconnected assemblage of weak arguments does not create a single, strong scientific argument.
Homeopathy, 2007, DOI:10.1016/j.homp.2007.05.008
Homeopathy, 2007, DOI:10.1016/j.homp.2007.05.006

Water memory's forgettable history

Next on our list is "The history of the memory of water" by Yolène Thomas, which begins with a recounting of some of the original work done by Jacques Benveniste. It descends into a diatribe against Nature for not supporting it and then describes Thomas' current experiments on something she terms "digital biology."
Benveniste brought water memory to wide attention by using it as an explanation for results he reported in Nature: extreme dilutions of a histamine-containing solution (where no histamine was present) still induced a response in tests for allergic reactions. Nature, expressing disbelief, agreed to publish the results provided that they could send an investigative team to verify that (a) there was no fraud and (b) the experimental procedure was rigorous.
The team discovered that no fraud had occurred, but the lab's analysis procedures led to a common statistical error that induced false positives during individual tests. Benveniste’s team had ignored long runs of negative results, introducing a strong selection bias over time. Under more rigorous experimental conditions introduced by the investigative team, only null results were produced.

Water memory ignores the past

According to one paper, appropriately patterned sound can induce a memory to form in water.

A scientific response to the Nature setback might involve repeated tests under appropriately rigorous conditions. But Thomas doesn't acknowledge that the original experiments were flawed, and he suggests that the Nature team simply asserted fraud. "Three of the four labs involved in the trial reported statistically significant inhibition of the basophil degranulation reaction by HD [high dilution] of histamine as compared to the controls. The fourth lab gave a result that was almost significant."
This is not a very encouraging argument, since a result that was almost but not quite statistically significant is, in fact, insignificant. The article doesn't address any of the specific deficiencies described by the Nature team, so we cannot tell if the methodology of more recent experiments is improved. The newer results have been published in peer-reviewed journals (and not only specialist homeopathy journals), so the scientific establishment is not preventing researchers from getting their results out, contrary to one of the themes mentioned by Chapman.
Thomas goes on to describe recent research that purportedly shows that recordings of white noise that has passed through a sample with the active ingredient can induce activity when broadcast at a sample of water. Unfortunately, Thomas chose incredibly complicated tests of activity using live animals, opening the door to artifactual results. A more reasonable approach has been suggested here.
It is pretty clear that Thomas and his coworkers still do not understand science very well, as results are reported in terms of success or failure. Experiments do not succeed or fail; they either report results in agreement or disagreement with your hypothesis—or, in the case of a badly designed experiment, randomly oscillate between agreement and disagreement. The following quote gives a pretty good clue about which of these three categories the experiment Thomas is running fits into: "More surprising and mysterious was the fact that in some cases certain individuals (not claiming special talents) consistently get digital effects and other individuals get no effects or perhaps block those effects (particularly when handling a tube containing informed water)."
Homeopathy, 2007, doi:10.1016/j.homp.2007.03.006

Spooky action at a distance in the non-quantum world

Homeopathy via entanglement of the practitioner, remedy, and patient. Too bad none of them are quantum objects.

Next, we move into quantum mechanics. Could water memory possibly be a form of entanglement? Lionel Milgrom seems to think so. But this doesn't appear to be quantum mechanics as we know it. "It is as if at a deep level, everything in the Universe is instantaneously linked together in a vast holistic matter-energy network of interacting fields which transcends ordinary concepts of space and time," Milgrom says. "And we, composed of trillions of particles are an inseparable part of it: far from what reason seems to tell us."
Reason, indeed, seems to tell us nothing of the sort. This is a serious misuse of scientific terms; "quantum mechanics," "entanglement," and "coherence" do not imply anything like that. The amount of time particles remain entangled is reduced by every interaction with other particles. As a result, at any particular moment, most particles in the Universe are not entangled with anything.
Milgrom next introduces some of the properties of water, also using the unusual method of analogy rather than actual description. He asserts that the preservation of structure in liquid water is only a small stretch beyond our present understanding of the transient structures formed by water molecules. But these structures have a lifetime on the order of a few picoseconds; something new to our understanding would be required for them to last for seconds, much less the months homeopathic remedies are stored. Milgrom proposes that the information is not actually carried by a structure of water molecules but is an emergent behavior of the whole. Exactly what emerges and how it emerges are, apparently, left as an exercise for the reader.

Entangling thermodynamics

Milgrom at least recognizes that emergent behavior in room temperature water is problematic, in that emergent behavior occurs only in systems with nonequilibrium thermodynamics. The paper does not say what the thermodynamic system is or what is out of equilibrium, but Milgrom asserts that a quantum description of the quantum critical points of an apparently classical system can explain the efficacy of homeopathy. At this point, we would expect to be introduced to the details of exactly where the quantum behavior manifests itself and how mixing and diluting changes that behavior. Instead, Milgrom performs a bait-and-switch by talking about superconductors and superfluids.
In the end, the quantum mechanical explanation for water memory appears to boil down to this: the practitioner who diagnoses the illness and mixes the medicine becomes, through observation, entangled with it. The person who is ill, through talking to said practitioner, becomes entangled with him—and, by drinking the mixture, is also entangled with the mixture. This entangled state allows the active ingredient to transfer its activeness to the patient. Apart from misunderstanding what constitutes an observer, Milgrom also misuses the concepts of entanglement and wave function collapse to create a system that sounds scientific but has absolutely no relationship with quantum mechanics.
Conveniently, this abuse of physics doubles as an explanation for the apparent non-efficacy of homeopathic remedies when they're tested. Apparently, these ideas "provide a rationale for why RCTs (Randomized Controlled Trials) of homeopathy often return equivocal results. It suggests the double-blind RCT 'collapses' the three-way patient–practitioner–remedy entangled state in a way analogous to that by which observation collapses a particle’s wave function in the Copenhagen Interpretation of orthodox quantum theory." In other words, the efficacy of homeopathy relies on us all averting our gazes.
Homeopathy, 2007, DOI:10.1016/j.homp.2007.05.002

Dilution without loss

After the dilution of a mixture, pounding the resulting solution on a table somehow re-establishes its memory.

Two additional papers discuss the process of dilution-succussion cycles. Homeopathic remedies are created by starting with a mother tincture (MT); this starting material is then diluted by adding some of its volume to a larger volume of solvent. Each dilution step is followed by succussion strokes, where the container holding the mixture is struck against a hard object a set number of times. The newly succussed mixture may be re-diluted and re-succussed many times over before being given to patients. The first paper in this set presents a mathematical model of these succussion-dilution cycles. Typically, scientific models of this sort are based on the well-understood properties of the substance being modeled. What David Anick models is a "(hypothetical) persistent structural feature in what is chemically pure water," a species he terms an "active ingredient." The term "hypothetical" seems like an understatement, given that water is well-studied, and there is no evidence that stable structures exist in a vial of reasonably pure water, and certainly not at room temperature and pressure.
Anick then seeks to model the concentration of these structures over the course of successive succussion-dilution cycles. He manages to model the dilution properly but invents his own physics to allow structures to spontaneously form during succussion. Chemistry and thermodynamics are pretty clear that this isn't possible. No molecules come for free after a banging against a hard surface.
Dr. Anick applies this questionable model to a variety of situations before ending on a point we agree with. "The model may not apply... if remedies are ultimately proved to be mere placebos or markers that support the ritual of healer-client interaction. The great weakness of the model is that it is inspired solely by clinical conventions with no direct experimental support." Here, for once, he is guilty of understatement, given that there are experimental indications that many of his assumptions are invalid.

It’s all in the glass

Water's memory might be based on silica, too. In contrast to electronics, nobody can say how it got there.

In a second paper, Anick evaluates silica derived from glass containers as a possible basis of homeopathy, suggesting that there are three things needed for the idea to be accepted. The first challenge is to "describe thermodynamically stable parameter(s) that not only show how remedies might differ from controls, but also how thousands of remedies can all be different from each other." The second challenge relates to what exactly happens during a dilution-succussion cycle. He phrases it this way: "Whatever pattern or information is in a remedy, it must somehow 'survive' being mixed into 99 parts of water, and then 'convert' the whole sample to that same pattern (or a slightly different pattern) when the whole is succussed." The third and final challenge is how water becomes altered by the original solute in the first place.
The paper offers a "silica hypothesis," suggesting that "vial-derived silicates [could] be the long-sought active ingredients in remedies." The hypothesis states that complex silicate structures can form during succussion strokes and that such structures may be able to answer the three challenges laid out above. The paper states that determining how such structures may be biologically active is beyond the scope of its work.
The problem is that glass exists as a near infinite network of chemically bonded Si(O_1/2)₄—there is no free SiO₂ to dissolve. Despite this, the author suggests that vials will typically contain a saturated or supersaturated solution of Si(OH)₄ monomer after the SiO₂ in the vial dissolves.

Contrafactual assertions

Undeterred, the article moves on to describing how solute molecules could seed silicate structures. It correctly notes that organic molecules can be used as templates for patterning silica structures. Since many initial homeopathic solutions contain organic matter, some of those molecules may act in this manner. When an organic molecule is used as a template in the real world, however, it becomes trapped inside the newly formed silica structure and cannot be used to template another one. The authors merely state that this doesn't apply to homeopathic solutions.
If we ignore this bit of science-by-fiat, there is still the second question: how does this work when the solution is diluted to the point where no template molecules are left? The authors suggest that previously formed silicates are able to replicate themselves and propose four methods for how this can happen. We must be blunt here: none of the four have any basis in reality.
Homeopathy, 2007. DOI: 10.1016/j.homp.2007.03.008
Homeopathy, 2007. DOI: 10.1016/j.homp.2007.03.005

Viewing experimental noise as signal

The entire journal was not composed only of reviews and polemics; a number of papers purported to provide experimental evidence of water memory. These studies suffer from a variety of flaws, but the clear message they send is that it's possible to perform scientific-sounding experiments without employing scientific methodology.
First up is a paper entitled "The 'Memory of Water': an almost deciphered enigma. Dissipative structures in extremely dilute aqueous solutions." The paper seeks to demonstrate and explain the memory of water via various measurements of homeopathic solutions. However, it also clearly states in the methods section:

"It is important to emphasize that, from the studies so far conducted, we cannot derive reproducible information concerning the influence of the different degrees of homeopathic dilution or the nature of the active principle (solute) on the measured physiochemical parameters."

The body of the paper describes a collection of experimental anecdote and artifact. A few graphs purport to show that the longer you leave a homeopathic solution, the stronger it becomes. Without so much as an error bar or any statistics and with the prior admission of no reproducibility, you could describe us as more than a little skeptical. We will at least give the authors points for maintaining a measure of scientific objectivity, since they acknowledge that impurities in the glassware used to prepare their solutions make up a significant part of their findings.
How they square this with the previous articles that claim dissolved silicates are in fact responsible for the homeopathic effect is unknown. About the only take-home message that can be gathered from this article is that if you look hard enough for information that supports your desired conclusion, you too can find what looks like a signal in background noise.
Homeopathy, 2007. DOI:10.1016/j.homp.2007.05.007

Experiments without an experimental method

We continue with a paper entitled "Can low-temperature thermoluminescence cast light on the nature of ultra-high dilutions?" It states, "Our research objective has been to try to demonstrate that the high dilutions are physically different from the diluent and have, indeed, an 'individual personality.'" This sums up the general approach of homeopaths to research: they are not out to investigate the properties of a system but rather to show that a system has the needed properties to justify their pre-ordained conclusions. This speaks volumes about their approach to science as a vehicle for respectability rather than as an investigative tool.
The author, Louis Rey, is investigating the defect structure of ice, an interesting topic. Homeopathic samples are frozen based on the untested assumption that the resulting ice will retain the structure imparted to the water. The frozen sample is then irradiated with high-energy photons (X-rays or similar). This removes some electrons from their normal, bound states, and they accumulate at defects in the ice. As the ice is reheated, the electrons overcome the energy barrier necessary for them to return to their bound state and release energy in the form of light as they do so. By monitoring the temperature and intensity at which the light is emitted, one can infer some information about the defect structure of the ice. Similar studies can be performed using more accurate methods, but we should emphasize that this technique is sound.

For whatever reason, Rey uses NaCl (table salt) or LiCl dissolved in heavy water. But the starting concentration is never given, so we only have a relative scale and never know when the last of the salt is gone. His experiments on "high" concentrations of salt (1/300 through 1/900 of the initial, unknown concentration) show a light peak that increases with decreasing dilution; the peak shifts to slightly lower temperatures at low concentrations. This is just crying out for analysis, but none is forthcoming. It isn't compared with a control, so we have no way to confirm that the active ingredient is influencing the results. The scale on the graph that shows the intensity of the emission is not clearly defined, and we are never offered a way to compare one graph to another. It gets worse. In the first graph, all the data is LiCl, and the ice is irradiated with an electron beam. The second data set uses gamma rays and water that contained different materials. Clearly, no comparison can be made between the graphs and, in some cases, between traces on the same graph. This alone means that we cannot accurately determine if the data sets are different—no effect, assuming one was present, could possibly be identified with this approach.
The experimental approach here highlights the contrast with science even more than the review papers. The experiments were designed to reach a specific conclusion, and standard scientific practices like controls and data normalization could be discarded en route to that goal.
Homeopathy, 2007, DOI:10.1016/j.homp.2007.05.004

Unexpected data produces logical leaps

Another data paper was entitled "Long term structural effects in water: autothixotropy of water and its hysteresis." The paper is written by two physicists who have been exploring anomalous results in a specific experimental system since the 1970s. The system involves a thin, flexible filament that is used to suspend a metal plate that is immersed in a covered container of water. Although none of these results appear to have been published, you can get a feel for them from a paper in the arXiv (PDF).
If water were an ideal, frictionless fluid, twisting the filament should create a stress that is immediately translated into rotational motion of the plate below it. In their hands, it does not, and not all of their observations can be explained via the differences between static and dynamic friction. This isn't a surprise; anyone who has suffered through a high school physics lab realizes that reality generally deviates from the ideal. The typical response by scientists is to try to identify any source(s) of the experimental error and eliminate or control for them.
These researchers have not chosen to go this route. Instead, they have given the deviation a name ("autothixotropy"), characterized the ways that the system differs from expectations, and concluded that it must result from a previously unrecognized property of water.
Autothixotropy’s key feature is that as the filament is rotated, plates submerged in water do not rotate immediately; instead, tension builds until the plate rotates suddenly. The resistance to the rotation increases with the amount of time the water has been left undisturbed and increases even more if the plate is only partially submerged. Resistance also increases if the water has been boiled and disappears entirely if the water is deionized. If still water is stirred, resistance vanishes but re-establishes itself more quickly than in freshly boiled water.

Jumping to unjustified conclusions

Collectively, the Ars staff can think of a half-dozen potential sources of at least some of these phenomena. And we're quite sure that the following wouldn't have been among them: "In terms of explanation, a hypothesis based on 'ephemeral polymerisation' of water seems plausible."
The paper is an odd mix of experimental results and implications that are normally put in the discussion. It also includes the first "moral lesson" we've ever seen in a scientific paper.

Moral: If two different observations seem to be mutually incompatible within the frame of an established theory, the most probable explanation is not that one of the observations is wrong, but that the theory is wrong or at least incomplete, and that the observations merely discovered that it was not self-consistent.

They're right in the sense that all theories are incomplete, but it's critical to add that not all puzzling data is an indication that a given theory is incomplete.
When the discussion arrives, there's no justification of the authors' conclusion that these phenomena point to the existence of complex structures in water, nor is there any contemplation of alternative explanations. Instead, the focus is on additional properties of the clusters of water molecules that are now assumed to exist. It's as if the authors felt that logically connecting A to B wasn't needed and they could jump straight to Q.
The very last sentence of the paper is the closest thing to science in the entire piece. The authors suggest that "[f]rom comparison of experiments with natural distilled water and deionized distilled water it is possible to deduce that the cause of macroscopic clusters of water molecules are the ions contained in water." It's phrased to assume the unsupported conclusions, but there are glimmers of a clue there. We could easily imagine a set of experiments using various (measurable) dilutions of a collection of salts that bring us closer to understanding at least some aspects of these observations.
As the authors have gone since 1978 without demonstrating this sort of scientific imagination, we expect they'll retire before performing these sorts of experiments.
Homeopathy, 2007. DOI: 10.1016/j.homp.2007.03.007

An explanation in search of a phenomenon

The special edition does contain a single article that acts as a counterbalance, one with the phrase "a sceptical view" in the title. Its abstract is quite blunt, saying, "It has been suggested that water could retain a "memory" of substances that have been dissolved in it before the successive dilutions. The paper stresses the fact that this idea is not compatible with our knowledge of pure water."
The author's point is that homeopaths should just give up on the whole "memory of water" thing—it just goes against too much of what we know. Instead, homeopaths should treat their medicine like any other, and subject it to a double-blind medical trial. To an extent, this comes across as a physicist (which the author is) trying to get the pseudoscientists to go bother some other field. But it's hard to argue with him; it would be the height of absurdity to rewrite much of what we know about chemistry and physics in order to incorporate an effect that hasn't been conclusively shown to exist.
Homeopathy, 2007. DOI: 10.1016/j.homp.2007.05.001

The symptoms of pseudoscience

Those of you who slogged through to the conclusion might be expecting to see a diatribe against homeopathy in general. But if the practice of homeopathy turns water into a mechanism for helping individuals feel better via a placebo effect, then the only issue with it becomes ensuring that it doesn't prevent people who really need medical intervention from getting it.
However, a subset of the homeopathic community has consistently demanded that their practice be viewed as both medically sound and scientific, presumably to obtain the credibility that traditional medicine receives. As our article reveals, they hope to achieve this without actually engaging in scientific practices. In doing so, they have adopted many of techniques used in other fields of pseudoscience:

• Ignore settled issues in science: We know a great deal about the behavior of water (and evolution, and other contentious topics), but there are many efforts to introduce new science without ever addressing the existing body of knowledge. As such, many of the basic tenets of topics such as homeopathy appear to be ungrounded in reality as we understand it.
• Misapplication of real science: Quantum mechanics is an undeniably successful description of parts of the natural world, but the limitations of its applicability are widely recognized by the scientific community (if not the general public). Pseudoscientists such as homeopaths appear to cynically target this sort of ignorance by applying scientific principles to inappropriate topics.
• Rejection of scientific standards: Over the centuries, science has established standards of evidence and experiment to ensure that data remains consistent and reproducible. But these strengths are presented as weaknesses that make science impervious to new ideas, a stance that is often accompanied by...
• Claims of suppression: Pseudoscience is rejected because it does not conform to the standards held by the scientific community. So, the pseudoscientists portray that community as a dangerous hegemony that rejects new ideas in order to perpetuate a stifling orthodoxy. This happens in spite of many examples of radical ideas that have rapidly gained not only acceptance, but major prizes, when they were properly supported by scientific evidence.
• A conclusion/evidence gap: Many areas of pseudoscience do not set out to examine a phenomenon but instead have the stated goal of supporting a preordained conclusion. As such, they often engage in excessive logical leaps when the actual data is insufficient to support the desired conclusion.
• Focusing on the fringes: All areas of science have anomalous data and anecdotal findings that are inconsistent with the existing understanding. But those anomalies should not obscure the fact that the vast majority of current data does support the predominant theories. In the hands of a pseudoscientist, these unconnected edge cases are presented as a coherent body of knowledge that supports the replacement of existing understandings.

Perhaps the clearest theme running through many areas of pseudoscience, however, is the attempt to make a whole that is far, far greater than the sum of its parts. Enlarging a collection of terminally flawed trivia does not somehow strengthen its scientific significance. This is especially true when many of the components of the argument don't form a coherent whole. For example, quantum entanglement, structured water, and silica are essentially unrelated explanations, and any support for one of them makes no difference to the others. Yet somehow, presenting them all at once is supposed to make the case for water's memory harder to dismiss.
In extracting these consistent themes, it was remarkably easy to recognize similar instances of most of them in many of the more contentious areas of pseudoscience, such as intelligent design, creationism, and denial of the HIV/AIDS connection. We've intentionally avoided discussing those topics in detail, but we hope those who read this article are willing to perform that exercise on their own.