ASSAP: Paranormal Research
ASSAP: Paranormal Education
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by Maurice Townsend

When a case appears to have a paranormal conclusion critics will quickly gather to pick holes in it. Distressing though this experience can be for the investigator, it is a useful process for improving our methods. When a case report contains a conclusion of ‘natural causes’ there is usually no such criticism. This is not such healthy state of affairs. Just because a 'natural' explanation has been found, it doesn't necessarily mean the case is over. It must be the right explanation, otherwise it is not science!


The paranormal is defined negatively. It covers those phenomena not explained by current scientific theories. It can therefore only be concluded that paranormal phenomena have occurred when there are no natural explanations to cover the incidents concerned. Investigations are therefore given over to proving the absence of natural causes. This is done by considering a variety of obvious natural causes and seeing if any of them explain the phenomena. This is always going to be a difficult process as someone can come along later and suggest a natural explanation you never considered. It may be too late at that stage to get any further evidence to test the new theory. Thus cases generally end up with one of two conclusions: ’natural causes’ or ‘unknown causes’ (implying possibly paranormal). There is always a possibility that the second conclusion may have to be changed to the first at a later date if new evidence emerges. More frustratingly, it could simply become a case of ‘insufficient evidence to tell’ if a possible natural cause emerges later when it can no longer be tested.

Unknown Causes

When investigators conclude that no natural explanation can be found for a case, it is a serious matter. The investigators will be expected to justify their conclusion with sound evidence, all of it negative (ie. explaining why it could not have been this, that or the other). Clearly there will be close scrutiny of the case and many people will reject it out of hand because it appears to be outside current scientific thought. This pressure may seem rather hard on an honest investigator trying to discover scientific truth, but it is no more than has been applied to many scientists down the centuries. Such scepticism is, in fact, perfectly healthy. Without it, science would simply become a series of untested assertions and observations. All scientific knowledge must be based on sound evidence which has withstood logical analysis. New scientific discoveries require extra scrutiny before they can be accepted as fact.

Natural Causes

Now, consider an investigator who has concluded that natural causes were indeed responsible for the phenomena in a particular case. This is exactly what happens to the majority of reports received by ASSAP. Often it is obvious that somebody has misidentified a phenomenon as ‘unnatural’ when it is not. The people who report such phenomena are usually not trained observers or scientists and often the conditions for observation are far from ideal. In addition, some observers may have personal beliefs that colour their perceptions. Even highly promising cases may be explained by natural causes after exhaustive enquiries. Very few cases make it all the way through untrammelled to the ‘unknown causes’ category.

However, there is a crucial difference between how this case report is received and how the previous one was. When investigators conclude that natural causes are responsible there is usually no close scrutiny of the report. After all, the conclusions do not challenge the status quo in science, therefore they are of little interest to most people. A case has been 'solved' and everyone is happy. The investigators may even get a warm feeling from reporting such a case. It does, after all, prove that they are not pushing particular beliefs and can accept negative results. It can even add to the credibility of their next positive case.

The trouble with this happy picture is that it means that ‘natural causes’ are hardly ever subject to the same critical scrutiny that ‘unnatural causes’ are. That is a pity, because it may lead to paranormal researchers dismissing cases or even whole phenomena as ‘only natural causes’ when it may not be true. I certainly do not want to encourage people to believe that every case ever found to have natural causes is in fact paranormal. Far from it! Any serious, neutral, active researcher will tell you that the majority of cases received have readily obvious natural causes. Rather, I want to encourage people to apply the same cutting edge of sceptical scrutiny to both ‘natural’ and ‘unnatural’ causes. If we do not, there is a danger of using differing standards according to case conclusion.

Examine Natural Causes Sceptically

I now want to examine some of the pitfalls of investigation that might lead to a false conclusion of ‘natural causes’. These are often fallen into by people who are too eager to rubbish ‘the paranormal’ before they even begin an investigation. Such people are likely to accept ANY natural explanation, whether it fits with the known case facts or not. But even careful, unbiased investigators can become less thorough as soon as a natural cause starts to look likely. Cases become less attractive if they do not challenge science and may be prematurely terminated.

Simulation is Not Proof

A favourite method of searching for natural causes is through simulation. Since the supposed paranormal effect is no longer taking place (which is true in most reported cases), you can attempt to recreate the circumstances of the original event. This is a valuable technique which often reveals unusual coincidences or misperceptions that can indeed account naturally for the phenomena reported. You can then try to recreate the effect by any plausible mechanism you can think of, even if there is no direct evidence of its happening that way. You could, for instance, insert an unseen person into a darkened room to see if he could have caused a weird effect undetected by the witness.

I would strongly encourage the use of this technique as it can suggest many possible natural causes that you may not have thus far considered. However, you should remember something very important about simulation. Showing how something COULD have happened is not the same as proving what ACTUALLY happened. One could no doubt sail from Ireland to South America in a coracle to show that the Irish discovered Brazil. But without finding ancient Irish settlements in Brazil, the conjecture is no more than speculation. Amazingly, however, some people believe that, if you can show how natural causes might have produced an effect, it cannot therefore be paranormal! This is neither scientific nor logical.

The answer is not to conclude your investigation at this point but to use your simulation as a starting point to look for more evidence. Firstly you can re-examine the original evidence to see if anything suggests that your simulation might be true. You may have missed such clues when first gathering evidence as you were not looking for them. Secondly you could re-interview the witness to deliberately search for evidence to back up your theory. If neither of these approaches produces anything to back up your theory, try looking at the scene of the original incident again. Would your hypothetical cause have produced any other changes to the environment that might still be visible now? For instance, if you hypothesised a strong draught causing an object to move, you could look for unusual patterns in any dust present in the room. The point is that your simulation is a working hypothesis - it needs to be tested (usually by looking for additional evidence) before it can be accepted as the most likely explanation.

A very important test to apply to hypothetical natural agencies is this. Should the agency have produced any other effects IN ADDITION to the apparently paranormal one observed by the witness? As an example, suppose you hypothesised that a lighthouse briefly illuminated an object in a darkened room, making it appear to suddenly glow in the dark. If you knew that the curtains were wide open at the time of the incident, then the lighthouse should have illuminated the whole room and not just one object. In this rather silly example it is fairly clear that, although the theory could account for the effect, it should have produced other obvious effects that were not observed. Therefore you can eliminate the theory from your enquiries. Astonishingly, this thought does not seem to occur to some people who are anxious to ‘solve’ a case as quickly as possible.

Obviously, if you do find evidence to back up your hypothesis then you can safely conclude natural causes are indeed to blame. Otherwise you can mention your hypothesis as an idea in your report but make it clear you could find no evidence to substantiate it.

Expert Knowledge

Are you an expert in geochemistry or biophysics? Most investigators will no doubt answer ‘no’ to this question. Expertise in specialised subjects such as these is sometimes required to propose and test plausible natural causes in a case. Unfortunately, this does not stop some people without such expertise from proposing explanations based on these subjects. Of course, people can teach themselves quite complex subjects from books in their local library or from the internet. However, this is hardly ever an adequate substitute for a formal course and years of research experience.

It is important to point out here that I do not want to discourage anyone from investigating simply because they have never studied science. Also, I would not want to discourage anyone from consulting library books to find out more about possible natural causes they suspect might account for reported phenomena. Rather I would say that if you are not an expert in a particular subject then consider consulting someone who is. Experience shows that writing to or emailing universities, official bodies (such as the British Geological Survey) or museums often produces useful answers. Though scientists are often very busy, they may well be intrigued by the questions you put and the subject you are studying even though they will rarely want to get involved directly.

If you come to the conclusion that natural causes are involved in a case and that they rely on science that goes beyond everyday knowledge, get an expert involved. Ideally your report should include a statement by a scientist with expertise in the area concerned. Of course, if you happen to be an expert geochemist yourself, just say so.

There are two main problems that occur when people stray unassisted into fields beyond their knowledge. Firstly, there is vagueness. By this I mean that someone may claim that such and such a phenomenon is due, for instance, to ‘sound resonating in a nearby abandoned mineshaft’. There is no attempt to show the precise mechanism whereby such sound reaches the surface, no discussion of what the resonating frequency of a mine shaft might be, no attempt to discover how the dimensions of the shaft or surrounding soil structure might affect the sound. In other words, all the sorts of questions that a sceptical scientist might ask are left unanswered. The vague assertion might be correct but no attempt has been made to justify it. Such vague assertions might be taken literally by a reader who assumes you are an expert.

The second problem is one of misunderstanding. Someone who is inexpert in a field might misunderstand some of the basic concepts without anyone to guide their thoughts. The ‘natural’ explanation they suggest for a phenomenon might actually be unscientific and quite unnatural! Thus a ‘natural’ explanation might ironically be ‘unnatural’! Consulting an expert could have easily corrected this problem and allowed a more plausible mechanism to be suggested.

We cannot all be experts in everything we come across in a case of anomalous phenomena. This should not discourage us from investigating provided we realise that we might need help.

To summarise: Try to test your proposed natural explanations. Is there any actual evidence in their favour? Are they scientifically plausible? Are they sufficiently detailed to satisfy an expert? Should your proposed mechanism have produced any detectable side effects at the time or left a residue to be found later? Be sceptical of your own skeptical explanations!

This article first appeared in Anomaly 21, Nov 1997