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Logical Fallacies — the Incorrect Cause


Skeptic kitteh sez...
Hey, guys. This post deals with a group of closely related fallacies of logic known as Incorrect Cause Fallacies, or more formally, Non Causa Pro Causa, the first one we shall deal with being Post Hoc, Ergo Propter Hoc, or After This, Therefore Because of This. This fallacy is very simply constructed, its form being…

  • Y occurred before Z, therefore Y caused Z.

…as per the following examples…

  • I wanted to get revenge on an enemy, so I danced around a table, said a few nonsense words that sounded profound, sacrificed a chicken, and a week later my enemy was injured in an accident. Therefore the ritual worked like I thought it would.
  • I had the flu, so I took some homeopathic remedy I got at the pharmacy and a few days later my flu went away. So I conclude that the remedy cured my flu.

Similar to this is Confusing Association with Causation, or Cum Hoc, Ergo Propter Hoc, (With This, Therefore Because of This), which like the above has a rather elementary, but subtly different construction from the previous fallacy…

  • X is found with Y, therefore X caused Y.

…note the distinctions in the assumption used in the first part of the argument, the premise, as the following will show…

  • I got a really good test score while wearing my propeller beanie, therefore wearing a propeller beanie makes you get better test scores.
  • My horoscope forecast a difficult day for me during the alignment of Pluto and Jupiter with the center of our galaxy, and that day was indeed very stressful and hectic. So I conclude that the cosmic alignment was responsible for the rough time I had that day.

As you can see, there are significant difference between the logical structure of the premises of these fallacies, since that of the first involves a sequential relationship in time, while the second involves finding two things together in a temporally coincidental relationship. Needless to say, these fallacies have resulted in much in the way of superstition and magical thinking throughout human history, including the present day, forcing skeptics to keep themselves at the thankless task of societal damage-control.

A variation on these is known as the Texas Sharpshooter Fallacy, specious reasoning in which one makes the false assumption of a causal relationship in, or spurious meaning to random data patterns, whatever relationship or meaning one wishes to see a priori, often unconsciously, and unfortunately done in some paranormal research with the occasional misuse of statistical methods, including the erroneous interpretation of statistical artifacts and anomalies as scientifically significant evidence for paranormal phenomena, as per occult statistics. This fallacy takes its name from a hypothetical gunman who randomly fired his pistol at the side of a building while no one was looking and painted bulls-eyes around the holes to prove his marksmanship ability.

There is also the misleading inference of a real causative relationship, as per the Wrong Direction fallacy, such as the idea that dental cavities cause the excessive consumption of sugary sweets and beverages, or that certain forms of male sterility cause ionizing radiation exposure.

Another is the Complex Cause fallacy, whereby one considers only one out of a set of causative agencies at the expense of the others, which results in an inference of causation that is only partially true, such as reasoning that the reading ability of children is caused only by physical development as they get older when it is actually caused by both age and education as they mature.

And there is the Joint Cause fallacy, in which one infers causation between a set of things, when they are all together mutually caused by the same agency, such as speciously inferring a causative relationship between childrens’ mathematical ability and their shoe size, this despite the fact that they are both caused by the relative age of the children as they mature and learn.

Finally, there is the Regression Fallacy, in which one infers that an agency other than the tendency for extremes of chance to deviate ever closer to the average of a statistical bell-curve over time is responsible for an event. A good example of this is a chess-player who has a strings of wins and losses in matches but tends to come out average over time, but who feels that he is winning, or losing, in ‘streaks,’ the well-known belief in the ‘hot hand,’ as it is known in sports.

A corollary to the Incorrect Cause fallacies is the Denial of Causation, such as when the fossil fuel industry promotes the claim that the human burning of fossil fuels doesn’t cause global climate change, that, for example, the increase in global temperatures is caused by an increase in the sun’s energy output, and that in and of itself, human-caused global climate change is impossible, despite the signs of solar activity in the last decade being the lowest it has been in years.

Another example of said corollary is the claim by AIDS contrarians that the HIV virus doesn’t cause AIDS, that there is no causative correlation between HIV in the blood of those with the disease and that any immune deficiency is simply caused by lifestyle and/or diet.

Be those as they may, however…

…It’s easily possible for any inference of causation one makes to be spurious, but science provides methods by which to make correct inferences. Important in any such argument of inference is taking into account any conceivable, and moreover, testable alternative hypotheses that could be implicated in the actual causation of a given phenomenon. Untestable hypotheses of course, needn’t be considered as they are scientifically uninteresting.

Baloney Detection 101: the Clustering Illusion


It doesn’t seem to make sense that truly random events would bunch together, or cluster, and this, the Clustering Illusion, is the perception that such events are non-random, unusual, significant, and meaningful.

This is based on a false supposition, derived from the psychological phenomenon of subjective validation, also known as selective thinking, or selection bias, a tendency to remember the events that stand out, or “hits,” and to dismiss from one’s mind and thus to forget the “misses,” those events that do not appear to get one’s attention or notice.

For example, while it seemingly makes no immediate sense that in a series of 20 coin flips that there is a 50% likelihood of getting a result of 4 heads in a row, and the fact that in any particular community, there might be a statistically significant number of those diagnosed with cancer, it’s the math, not our intuition that is correct, and once you actually do the math, it makes a lot more sense.

It would be unusual, highly unexpected, and highly improbable that each of only 20 coin flips would be the opposite of the previous flip. And it is even less likely that in any given sequence of random coin flips, that short runs will give what would logically be expected.

In any small sequence of random events, a wide range of probabilities, even and especially those that run counter to what we would consider sensible, can and should be expected to happen. Statistically odd events not only do happen, they can be expected to happen by the laws governing chance alone, without the need to invoke anything out of the ordinary.

Just because an apparently paranormal event happens more frequently than chance would seem to indicate, it does not logically follow that it is not due to chance. The laws of probability as we know them can and do predict such events, and these clustered events are random, even if they seem to be immediately unexplainable and non-random.

Anomalous cognition researchers often mistakenly interpret a run of apparent successes by their test-subjects as evidence for psychic ability, or seemingly statistically significant failures as evidence of ‘psi-missing‘ or Antipsi, and that such varies over time.

This is derived from simply ignoring or ignorance of perfectly ordinary random probabilities. The clustering illusion is also known in logic as the Texas Sharpshooter Fallacy, the Belief in the Law of Small Numbers, and the Division Fallacy, the erroneous assumption that parts of a whole are identical to the whole.

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