The reception of unconventional or extraordinary claims in science has come under increasing attention by sociologists and historians. Scientific anomalies have sparked scientific revolutions, but such claims have had to fight prejudices within science. This essay offers scattered reflections on the adjudication process confronted by protoscientists (science "wannabes") wishing admission into the scientific mainstream. My comments here are not intended in support of proponents of the paranormal (for I remain a skeptic, as defined below) but to help produce a more level playing field and a greater fairness that might help all scientists.

Equilibrium in Science.

Philosopher Paul Feyerabend asserted that in a free society, science is too important to be left entirely to scientists. He had a point, for institutionalized Big Science has brought with it increased vested interests, some of which may threaten scientific growth itself. Though many historians and philosophers of science remind us that science needs to remain a tentative and open system, both fallible and probabilistic, science may, as do other human institution, develop orthodoxies and even dogmas.
Historian Thomas Kuhn spoke of the "essential tension" in science between its conservative need to accumulate a body of tested knowledge and its progressive need for innovations from theory and data that might lead to new paradigms. So, a successful scientist performs like a circus wire-walker, engaged in a balancing act with closed minded arrogance weighted at one end of the balancing pole and open minded credulity weighted at the other. If either end pulls too far, a fall may follow.
Today, I think the balance has shifted too far towards arrogance. The emergence of a new and quasi-religious dogmatism, usually termed Scientism, has been examined and criticized from diverse standpoints in recent years, particularly those of Tom Sorell, Mary Midgley and Bryan Appleyard. Though some critics of Scientism take an anti-science stance, we need not go so far to recognize some current excesses. And though some postmodernists and others question the basic epistemology of science, my concern here is only with metaphysical debates over what phenomena science should judge to be "real," especially controversial claims for the reality of anomalies (ranging from alleged processes like extra-sensory perception and psychokinesis --the claims of the parasciences-- to bizarre physical things like bigfoot and UFOs -- the claims of the cryptosciences). My complaints here, then, are only with scientists' violations of their own professed method; in fact, I agree with those who contend that science fundamentally IS its method rather than its tentative substantive content.

On Impossibilities and Errors.

In their "Introduction" to No Way: The Nature of the Impossible, mathematician Philip J. Davis and physicist David Park concluded that although we may have conceptions of the impossible, we cannot have absolute knowledge of it, for "There is no criterion of impossibility." In line with this, philosopher Charles Sanders Peirce earlier argued that our first obligation must be to do nothing that might block inquiry. Yet, some, claiming to speak in the name of science now demand doors be closed on many subjects. Although science can only assert that extraordinary events are highly improbable, some critics speak of "laws of denial" as though we can prejudge some empirical events impossible so unnecessary to investigate. Such defenders of the status quo often engage in ridicule and sarcastic rhetoric that is deemed uncivil in normal scientific discourse, and sociologists of science Harry M. Collins and Trevor J. Pinch have gone so far as to characterize some such activities as scientific "vigilantism."
Such defenses of orthodoxy are not surprising, and they typically stem from an honest desire to avoid mistakenly thinking something special is happening when it really is not (what statisticians have termed a Type I Error). This error is embodied in the aphorism "all that glitter is not gold." However, proponents of esoteric claims are often more concerned with avoiding the mistake of thinking nothing special is going on when it actually is (the statistician's Type II Error). Their attitude is exemplified by the folk maxim that we "should not throw the baby out with the bath water." These contrasting types of error, and our need to follow a path avoiding both, are central to Kuhn's "essential tension" in science; and I think much of the difference between proponents and critics of extraordinary claims in science may center on which of these two types of error is designated as the more dangerous. The Chinese character for "crisis" consists of combining the symbols for "danger" and "opportunity." Such is the case with the paradigm crisis inherent in an extraordinary science claim, usually consisting of an alleged anomaly (a fact in search of theory). Conservatives in science typically view anomalies as dangers (threats to currently accepted theories) whereas progressives (proponents) of such claims see them as "opportunities" (stimulants for theory reconstruction).

On Heresy, Scientism and Discrediting the Paranormal.

As conservative science confronts the threat of anomalies, it may defend itself with excessive zeal. So much so that some organized critics of anomalies have even been characterized as a "New Inquisition" seeking to stamp out the heresies against an orthodoxy of Scientism. Ironically, since he was himself a prominent critic of many anomaly claims, Isaac Asimov distinguished between "exoheretics" (outsiders to a field)) versus "endoheretics" (insiders or professional colleagues) in science. Endoheretics are usually accorded greater courtesy than are exoheretics. Thus, I have found, endoheretics are more likely to be described as "cranks" (tenacious) and as making "errors," while exoheretics are openly called "crackpots" (crazy) and are accused of "fraud." The strongest pejorative labels such as "pseudoscience" and "pathology" tend to be ascribed to the claims and methods of exoheretics.
In the effort to discredit anomaly claims, critics often characterized them as "miracles," and any connections with past religious or occult support tends to get them labelled "supernatural" or "magical." This is particularly unfortunate, because terms like "paranormal" were originally introduced to naturalize the supernatural. Protoscientific proponents of the paranormal insist that the paranormal is part of the natural order and consists of anomalies amenable to scientific investigation and possible verification. While occultists and theologians have recognized this difference between the paranormal and the supernatural, many "scientific" critics merely lump them together as "transcendental nonsense." Because of this, many critics of the paranormal mistakenly invoke David Hume's famous argument against miracles when dealing with claims of the paranormal. In fact, Hume distinguished between merely extraordinary events and miracles (which must involve divine volition and a suspension of the laws of nature). Most critics of the paranormal seem unaware of the voluminous literature distinguishing "marvels" (anomalies of nature) from "miracles." A major practical consequence of such semantic confusion is the false impression that anomalies can largely be discredited a priori so need no further investigation. Such rhetoric thus blocks inquiry.
As psychologist Ray Hyman has noted, many scientists may be more interested in discrediting than in disproving claims of the extraordinary. This can lead to poor scholarship and methods below normal professional standards, and it also results in ad hominem attacks and rhetorical tricks rather than solid falsification. Hyman noted it can also lead to the use of "hit men" (nonscientists such as journalists or even magicians) encouraged to discredit the claimants. Such nonscientists have argued about the need to "fight fire with fire" and the advantages of "horselaughs" over arguments and evidence. Such counterattacks themselves constitute a form of pathology within science. As philosopher (and critic of the paranormal) Mario Bunge put it: "the occasional pressure to suppress it [dissent] in the name of the orthodoxy of the day is even more injurious to science than all the forms of pseudoscience put together."

Skeptics or Scoffers?

Perhaps the most insidious rhetorical trick has been the misappropriation of the label "skeptic" to describe what are actually scoffers . As sociologist Robert K. Merton pointed out, organized skepticism is a fundamental norm in science. However, the term skepticism is properly defined as doubt, not denial. It is a position of agnosticism, of nonbelief rather than disbelief. The true skeptic (a doubter) asserts no claim, so has no burden of proof. However, the scoffer (denier) asserts a negative claim, so the burden of proof science places on any claimant must apply. When scoffers misrepresent their position as a form of "hard-line" skepticism, they really seek escape from their burden to prove a negative position.
Perhaps the greatest confusion related to the needed distinction between skeptics and scoffers concerns their different reactions to the failure by a claimant to support an anomaly claim. The skeptics' attitude towards extraordinary claims (for example, those of parapsychology) where proponents have so far produced inadequate evidence to convince most scientists that their hypotheses about anomalies are true is characterized as a case not proven. A skeptic contends that "the absence of evidence is not evidence of absence." The scoffer, on the other hand, sees the failure of proponents as evidence that an anomaly claim has been disproved. The perspective of the scoffer, as with most dogmatists, tends to distinguish only black from white and fails to acknowledge gray areas. (Our criminal justice system may likewise be too dichotomous. Thus, similar reasoning led some citizens to conclude that the murder acquittal of O.J. Simpson meant he was judged innocent when he was merely found to be not guilty. Science might better follow the path of Scottish Law which allows for three possible judgements: guilty, not guilty or innocent, and not proven.) Scoffers use a similar foreshortening towards issues of evidence. It is common to hear statements to the effect that "there is no evidence supporting a claim" when in fact it is merely inadequate evidence that has been presented. Evidence is always a matter of degree, some being extremely weak; but even weak evidence can mount up (as shown by meta-analysis) to produce a stronger case. Weak evidence (most commonly anecdotal rather than systematic and experimental evidence) is often discounted, however, by assertions that it falls below some threshold of what science should consider evidence at all. This, of course, eliminates the evidential basis for most of clinical medicine and the social sciences, but that seems to hold no terror for the scoffer who invokes such criteria.

Shifting Goal Posts and Rubber Rulers.

As proponents of anomalies produce stronger evidence, critics have sometimes moved the goal posts further away. This is especially clear in the case of parapsychology. To convince scientists of what had been merely been supported by widespread but weak anecdotal evidence, parapsychologists moved psychical research into the laboratory. When experimental results were presented, designs were criticized. When protocols were improved, a "fraud proof" or "critical experiment" was demanded. When those were put forward, replications were demanded. When those were produced, critics argued that new forms of error might be the cause (such as the "file drawer" error that could result from unpublished negative studies). When meta-analyses were presented to counter that issue, these were discounted as controversial, and ESP was reduced to being some present but unspecified "error some place" in the form of what Ray Hyman called the "dirty test tube argument" (claiming dirt was in the tube making the seeming psi result a mere artifact). And in one instance, when the scoffer found no counter-explanations, he described the result as a "mere anomaly" not to be taken seriously so just belonging on a puzzle page. The goal posts have now been moved into a zone where some critics hold unfalsifiable positions.
Scoffers are typically quick to demand good methodology when dealing with extraordinary claims, insisting on such things as replications, control groups, double-blind experiments, and the rule of parsimony (Ockham's Razor). They often write of the cognitive fallacies committed by paranormalists. In the process, however, they overlook the same need for rigor in many areas they defend. Thus, alternative medicine is denounced for its failure to demonstrate claims with proper experiments, ignoring the absence of experimental evidence in many areas of orthodox medicine (for example, in surgery). And scoffers denounce "psychic" counsellors but don't bother to do controlled experiments comparing them to orthodox advisors such as psychiatrists, clinical psychologists, and social workers.
Psychologists who complain about inadequate replication levels in parapsychology seem unaware of the dismal record of replication with conventional psychology. They also fail to note that what constitutes a replication is itself often a matter of controversy, and, as Harry Collins has shown, often involves social negotiation.
Astronomers who inveigh against neo-astrology seem unbothered by the nonfalsifiability of many current fashions in their own cosmological theories, and they seem to have forgotten that gravity was once rejected by Newton's fellow scientists over the assertion that there could be "action at a distance." Scoffers seem to assume a unity in science, forgetting that history reveals many disagreement among science's branches, such as physicist Lord Kelvin's (then reasonable) arguments against Darwin's theory of evolution since the sun was too young to allow the time Darwin's theory required (fusion had not yet been discovered).
The rule of parsimony asserts that the simplest adequate theory should be preferred, but, as Mario Bunge has shown in his book on the subject, the concept of simplicity is far from a simple matter. In addition, the presumption that conventional explanations adequately cover extraordinary claims is usually the very issue at hand, so invoking parsimony can sometimes beg the question.
When criticizing the paranormal, scientists who are scoffers usually fail to bring the same professional standards expected of them in their own fields. This is particularly evident when one looks at their praise for articles reporting experiments on the paranormal that obtained negative results. Some of these articles contain questionable methods and conclusions and probably would never have passed peer review had they shown positive results.

Extraordinary Claims versus Extraordinary Proof.

In his famous 1748 essay Of Miracles, the great skeptic David Hume asserted that "A wise man...proportions his belief to the evidence,"and he said of testimony for extraordinary claims that "the evidence, resulting from the testimony, admits of a diminution, greater or less, in proportion as the fact is more unusual." A similar statement was made by Laplace, and many other later writers. I turned it into the now popular phrase "extraordinary claims require extraordinary proof" (which Carl Sagan popularized into what is almost the war cry of some scoffers). As anomalistic psychologists Leonard Zusne and Warren H. Jones observed, this demand "may be not only used but misused to the point where no amount of evidence of a paranormal claim will avail against a skeptic who has already prejudged the issue." The central problem however lies in the fact that "extraordinary" must be relative to some things "ordinary." and as our theories change, what was once extraordinary may become ordinary (best seen in now accepted quantum effects that earlier were viewed as "impossible"). Many now extraordinary claims may become more acceptable not when they are replicated but when theoretical contexts change to make them more welcome.

A Catch-22 in the Burden of Proof?

In criminal law, the burden of proof is assigned to the prosecution; in the court of science, it is placed on the defender of the deviant science claim. Whereas, in our British-based legal system, the defendant is presumed innocent until proven guilty, in science the maverick scientist is presumed "guilty" (of error) until proven "innocent." This is appropriate since science must basically be conservative in its own defense against myriad would-be invaders. But it is important to remember that the proponent of the paranormal has an uphill battle from the start. The chips are stacked against him, so his assault is not so threatening to the fabric of science as scoffers often characterize it. In a sense, conservative science has "the law" on its side.
In law, we find three varieties in the weight of burden of proof:

1. proof by preponderance of evidence,
2. clear and convincing proof, and, in criminal law,
3. proof beyond a reasonable doubt.