Logical Fallacies — Special Pleading
Posted by Troythulu
Special Pleading, or ‘covering one’s ass,’ is a form of argumentation skeptics routinely encounter, and is the concoction of excuses, often called ‘reasons’ by those prone to use them, also known as the ad hoc (or ‘in this case only’) hypothesis, and post-hoc reasoning. This is most often used in the form of arguments that try to ‘explain’ special reasons or invoke a presumed special case in an attempt to rescue a particular claim despite any logic or evidence against it, to dismiss a question, argument, explanation, or lack of evidence as somehow and uniquely not applying to the claim to be salvaged from the jaws of death.
- I took the paranormal challenge, but I couldn’t pass it because I was overwhelmed by the doubt of the skeptics present, which scrambled my powers…
- I failed the test because the stars weren’t right…
- The spirits weren’t favorable to my winning the challenge…
- I was unable to pass the preliminary test because the guy conducting it was a magician who cheated to make me fail by using sleight of hand…
- I couldn’t get a ‘hit’ on my remote viewing test because the target images in the envelope didn’t have a single, distinct, easily visualized (read: easily guessed…) feature for me to to focus my powers on…(remote viewing is myopic?)
- Psychics are real, despite what skeptics claim, but parapsychology has been unable to prove it for over 150 years because researchers have all along been looking in the wrong places and using the wrong methods…
That last one was actually suggested by someone I spoke with a couple of years back. However, even if this is a valid reason for the persistent failure to independently replicate positive results from earlier studies in later studies using the same testing paradigm, unless the claimant can suggest what those correct methods and places might possibly be, it is not very helpful, and brings us no closer to establishing the Psi hypothesis than before. And if the claimant can suggest the correct ways and places, then please, they should kindly inform the parapsychologists of what those are so that they can finally end this (not so) Great Debate once and for all!
This fallacy is prevalent in parapsychology with the so-called Experimenter Effect, recently dubbed by disgruntled parapsychologists the Wiseman Effect (after psychologist Richard Wiseman… Wow! I wish I was notorious enough to believers to have a logical fallacy named after me!) where skeptical disbelief, even accusations of repressed skeptical disbelief in those who sincerely hold themselves to believe, is said to produce an effect that literally in and of its magical self cancels psi-ability in a laboratory demonstration. How can the proponents of psi lose? After all, if you get a positive effect-size, it’s due to a psychic effect, and if you don’t it’s still due to a psychic effect! Really… how do you test that by itself to know if there’s anything really going on? –You can’t. However, here is the non-paranormal form of the experimenter effect that can be tested apart from psi with any area of science.
…and stealing from myself, there’s this one from one of my older posts…
- There really are pixies playing in my garden, but you can’t see them because they’re shy and don’t want you to see them, magically invisible to both optical and infrared light, and can’t be made visible by sprinkling stuff on them because they’re also intangible at will, and oh, did I also mention that you can’t hear them because they’re supernaturally silent whenever they feel like it?
Special pleading can be and often is carried to ridiculous lengths in gross disregard of the skeptics’ rule of thumb known as Occam’s razor, a tool of reason in which smaller leaps of logic are considered preferable to great ones, and in which “elements should not be multiplied unnecessarily,” or more to the point, beyond the plausible ability of the available evidence to support them.
Any argument using this fallacy is thus rendered both unfalsifiable and unprovable, and any idea in science should be framed in testable form, or it is not science. It does no good to say, “you can’t judge my claim because of special reasons X, Y, and Z,” or to provide any other arbitrary excuses that something won’t work, or can’t be tested.
Science is messy, and there are times when a theory must be refined so that it better conforms to the data, but this is not the use of post hoc reasoning: the amendments made to a set of ideas in science are those hypotheses that can be tested independently of the theory, and are those factors which are known to separately exist and have been observed in some fashion.
It’s bad form to have to come up with not only untestable, but irrelevant reasons to prop up an idea that not only fails the test of observation, the test of explanation, and the test of prediction, especially when it has no proverbial leg to stand on as with any flawed idea that forever remains such.
(Last Update 2010/04/02, Text, Image and Link Added)
About Troythulu
I seek to learn through this site and others how to better my ability as a person and my skill at using my reason and understanding to best effect. I do fractal artwork as a hobby, and I'm working to develop it to professional levels, though I've a bit to go till I reach that degree of skill! This is a crazy world we're in, but maybe I can do a little, if only that, to make it a bit more sane than it otherwise would be.Posted on Saturday, 11:16, February 20, 2010, in Logic/Philosophy and tagged Ad Hoc Hypothesis, Logic, Logical Fallacies, Logical Fallacy, Occam's Razor, Philosophy, Special Pleading. Bookmark the permalink. 4 Comments.

Where you say that the post hoc reasoning fallacy is prevalent in parapsychology with the so-called Experimenter Effect – what you call the Wiseman effect – you must be unaware then of the experiment conducted by Wiseman and Schlitz that actually demonstrated this effect in a predicted manner. Bother Wiseman and Schlitz, one an anti-psi researcher and the other a pro-psi researcher, conducted the same psi experiment under tightly controlled conditions and Wismean got no psi effect, whereas Schlitz did… AS PREDICTED prior to the experiment because of the experimenter psi-belief effect. It is known that psi belief is the best ‘predictor’ (I use this word again, this is not a post hoc reasoning) of psi performance. This effect is actually pretty robust. You should take a closer look at the literature. Cheers. DrD
Sorry, DrD, nice try, but I read about that study. The fact that one got results, and the other didn’t is the very thing the Experimenter effect tries to explain, and unfortunately there’s no way to test it independently of that, so there’s no way to tell if the so-called ‘effect’ even exists.
Any hypothesis used to explain a phenomenon has to be testable independently of the theory it’s meant to support or it’s scientifically useless — it has to be shown to exist on its own, or it’s ad hoc, and therefore of no consequence. That’s like proving a hypothesis of the physics of fluorescent lights by doing the very thing that the hypothesis is supposed to explain, what happens when the switch is flicked, just by flicking the switch. Needless to say, that’s not good science.
So the so-called Wiseman effect invoked by pro-psi researchers can be considered not only special pleading, but other logical fallacies such as begging the question, or depending on how it’s phrased, affirming the consequent. You would help your cause immensely by educating yourself on the particulars of scientific reasoning. Ciao. Troythulu
Oh, one more thing… The Experimenter effect has been invoked under various names for a long time in parapsychology, such as the ‘shyness effect’ or the ‘observer effect,’ and was originally conceived after the fact (post hoc) by pro-psi investigators as an attempt to explain the fact that it was not possible to replicate the results of a study independently of the attitude of the researcher.
This is a strong indicator that what is being looked for isn’t a real phenomenon, like a study done some time ago that found a correlation between enthusiasm for a phenomenon (in this case a surgical procedure of dubious worth known as the portacaval shunt (look it up)) and the spurious obtainment of positive results. It’s more likely that the strong belief of parapsychologists is producing the illusion of an effect by subconsciously influencing how they interpret the data.
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