This article originally appeared in The Skeptic, Volume 1, Issue 1, from 1987.
In the ordinary courses of our lives, we come across new facts and later find explanations for them. In childhood, we deal with simple things, the sort we take for granted as adults. For example, when you turn on the hot water tap, the first part of the water is cold. You later learn that only in the large hot water cylinder can water be kept hot for long periods: the water in the pipe supplying the tap gets cold.
I can recall in my youth a bathroom where the cold tap produced hot water at the start. I felt sure that the hot and cold pipes were mixed up in some way. I learned the true explanation from an adult: there was no cross-connection of water between the hot and cold systems, and the taps were correctly marked. I am not giving the full explanation now because I want readers to experience the position of knowing about an unusual event, but not knowing the explanation. (Of course some readers will be able to work it out for themselves.) This will help with the problem of explaining. (or not being able to explain) more serious events in the rest of the article.
Unidentified Flying Objects (UFOs) came to public prominence after 1945, especially in the USA. An object seen in the sky is initially called a UFO when a person sees it and cannot for the moment say what it is. Many of the surveys on UFOs start by collecting such eyewitness accounts. Then they interview other witnesses to the same events. They also check. for aircraft and spacecraft with the appropriate sources, and they review weather and astronomical records for the times of the sightings. By these means, most of the objects originally dubbed “UFOs” have been identified as aircraft. spacecraft, planets, ball lightning, ground lights, etc.
One such survey, the US Air Force Project Blue Book, found that 94% of UFO reports could be thus explained. The remaining 6% of cases are “unexplained.” For some people that is all there is to be said. But there are others who fell this residual 6% are “true UFOs” – that they cannot be explained by anything in my list above but have another explanation – perhaps that they are craft from distant planets paying us fleeting visits. However, this is not because of any physical evidence left behind on Earth and available for examination. Rather, it is a jump into the unknown, as I hope to show in my next example.
When a person dies, the cause of death is officially registered. In peacetime the vast majority of deaths are from natural causes, and by a doctor who has seen the person before death can certify the cause. The remaining cases must be investigated by police and pathologists. Such deaths may be from natural causes (not seen before death by a doctor), murder, suicide, or accident. The post-mortem result or the circumstances of the death generally put it clearly into one particular category.
However, some deaths resist categorization. A body is pulled out after a week or two in the sea, and “marine digestion” has removed the facial features so that the person cannot be recognised. The amount of water in the body makes it reasonable to suppose that the person drowned, but did he or she fall in by accident, or throw him – or herself in, or was he or she pushed? So, one out of every eight thousand deaths in Dublin City cannot be put into one “unexplained cases” is either murder, or accident, or suicide, or due to natural causes, only we haven’t enough information to decide which. The police may feel that one case was a murder. The relatives of the dead person may feel it was an accident, while the doctor privately feels it was a suicide. Nobody makes up a fifth category to put them into. People put up with the uncertainty here.
We humans feel uncomfortable with an unexplained event. Some of us, in some circumstances, find such a puzzle so difficult that we make a jump, as with the residual 6% of UFO claims. But if we were to follow the example of the death of indeterminate cause, we would say that these sightings were “either aircraft. Or comets, or planets, or rockets, etc, but we don’t know which.”
For those who were puzzled by the cold tap producing hot water, its pipe lay alongside a long run of hot pipe, and was thus warmed up. After this section of water came out, the cold tap was really cold.
