Common Fallacies (mistakes of reasoning) The fallacy fallacy • There is danger even in the study of fallacies. This study involves identifying certain patterns of reasoning as fallacies. Each pattern has a name. E.g. an argument that attacks a person is ad hominem. But ad hominem arguments are not always fallacies! • Rejecting an argument as a (named) fallacy, based on its pattern alone, is a fallacy that we might call the fallacy fallacy. • In general, an ad hominem is only legitimate when attacking an argument from authority. • But not all such attacks on authority are legitimate. They can be made on irrelevant grounds. Irrelevant ad hominem E.g. Einstein’s physics was attacked on the basis of Einstein being Jewish. Thomas Powers, Heisenberg’s War, p. 41 Fallacy? • Alliance leader Stockwell Day argues that Canada should increase its military expenditure now, by at least 20%, in order to continue to meet our NATO obligations five years from now. But Day is a fundamentalist who thinks the universe is only 6,000 years old! Clearly his view can be dismissed. • Mr. Wilson, in his letter of January 16, argues that it would be counter-productive to yield to the demands of the hostage takers. He does not, I take it, have a son or daughter among the hostages. As such a parent, I am repelled by his callous attitude. My daughter could well be the next innocent victim of these terrorists, but Wilson apparently doesn’t give a damn about this. 1. Comment on the following ad hominem (to the person) arguments, explaining why they are, or are not, reasonable. (i) Dr. Everett says that my rash is nothing to worry about – just a mild allergy of some kind. -- And you trust Dr. Everett? Didn’t you hear that he cheated on his wife? (ii) Dr. Malcolm Wardlaw argues, in the British Medical Journal, that wearing a helmet while cycling is unnecessary, since even bare- headed cycling is much safer than driving a car. -- Yes, but Wardlaw is a well-known opponent of bike helmets, so he’s biased on this issue. (iii) Gillette does indeed shave closer and smoother. Tiger Woods says so, and he’s probably the best golfer ever. -- He sure hits the ball well. But that doesn’t make him an expert on razors. I find Gillette no better than the generic brands. (iii) I wouldn’t buy that truck you’re thinking about. Brandy McElroy reviewed that model in Truck Weekly and said that it’s aimed at posers who just want to drive in the city. It looks aggressive, but underneath they’ve cut a lot of corners and it won’t stand up to heavy work. -- Ok, whatever. You’re going to ask a woman which truck to buy? She probably just thought the vanity mirror was too small. (iii) Apparently there are no buses today because it’s Saturday. I just asked that taxi driver over there. Fortunately he says he can take us to the hotel. -- Oh please! He’s a taxi driver. Of course he would say that. Appeal to Pity • An appeal to pity tries to get us to believe something, or do something, on the basis of pity and similar emotions. • More generally, this can be called an “appeal to emotion”. Appeal to Pity • You say that my essay is only worth a ‘B’, but how can that be right? I worked so hard on it! Also, I need a better grade or I risk losing my scholarship, which would cost me thousands of dollars. I might even have to drop out of school! When is pity a good thing? • An appeal to pity isn’t always a fallacy. When is it ok to take emotion into account? • Pity is sometimes an appropriate basis for action, but never for belief. • The function of emotions is to provide energy for right action, not to help us determine what is right. Plato’s chariot analogy of the soul • Reason decides where to go. • Emotion provides the power to get there. No cherry picking Pity, as a basis for action, must be based on all the relevant facts. (Once again, actions based on cherry-picked evidence are unjustified.) E.g. the case of the man who, having killed his mother and father, throws himself on the mercy of the court because he is an orphan. (v) I can’t believe you! You really think that children who grow up in single-mother households are at greater risk of becoming criminals? Those mothers are some of the hardest-working, self-sacrificing people on the planet! Imagine how they’d feel if they heard you say that! What a slap in the face! Straw Person Straw Person • A straw person fallacy is committed when one person misrepresents (e.g. distorts, exaggerates, caricatures) the opinion of argument of someone else. • Why would anyone do this? • Since the “straw person” is easier to refute. Straw Person Betty: When you hear about a scientific study, you should ask who funded the research, as this may indicate a source of bias. For example, if an oil company funds a study on the health effects of a gasoline additive, the results may be biased, and should be treated with caution. Anything wrong? Fred: I see where you’re going with that: No scientist whose research is funded can be trusted. I suppose you think that scientists should work for free? Nowadays, of course, science needs big money – get used to it! Straw Person • My liberal, environmentalist friend believes in preserving species, that the spotted owl and the snail darter are more important than people. • Why the liberals think that registering firearms will end gun violence is beyond me! Genetic fallacy • Rather than examining a person’s beliefs from a rational perspective, in terms of evidence and logic, see them as a symptom of (mental) disease, i.e. psychopathology. • I.e. one is “taking a psychological stance”, rather than a logical one. • This means giving up on understanding the reasons for a person’s belief, and evaluating the strength of the evidence for them, and instead seeing the belief as caused by some illness, or other personal circumstances. Mary thinks that expanding the business right now would be a mistake. The Asian markets are showing signs of weakness, which could mean big trouble for us. -- I wouldn’t worry about that. I think maybe it’s Mary’s “time of the month”. “Religion is an attempt to get control over the sensory world, in which we are placed, by means of the wish- world, which we have developed inside us as a result of biological and psychological necessities. [...] If one attempts to assign to religion its place in man's evolution, it seems not so much to be a lasting acquisition, as a parallel to the neurosis which the civilized individual must pass through on his way from childhood to maturity.” –Sigmund Freud, Moses and Monotheism, 1939 “Medical materialism finishes up Saint Paul by calling his vision on the road to Damascus a discharging lesion of the occipital cortex, he being an epileptic. It snuffs out Saint Teresa as an hysteric, Saint Francis of Assisi as an hereditary degenerate. George Fox’s discontent with the shams of his age, and his pining for spiritual veracity, it treats as a symptom of a disordered colon. Carlyle’s organ-tones of misery it accounts for by a gastro-duodenal catarrh.” William James, Varieties of Religious Experience. Example • “A report scheduled to appear in an upcoming Applied Cognitive Psychology offers a preliminary psychological profile of people who believe in 9/11 conspiracies. A team led by psychologist Viren Swami of the University of Westminster in London identified several traits associated with subscribing to 9/11 conspiracies, at least among British citizens” (From U.S. News, May 26 2009.) “These characteristics [of 9/11 conspiracy believers] consist of: • backing one or more conspiracy theories unrelated to 9/11 • frequently talking about 9/11 conspiracy beliefs with likeminded friends and others • taking a cynical stance toward politics • mistrusting authority • endorsing democratic practices • feeling generally suspicious toward others • displaying an inquisitive, imaginative outlook” Jonathan Kay, Among the Truthers, 2011. “The children grow up, the hair falls out, careers plateau, physical powers ebb….. Like all forms of midlife crisis, the sudden lurch into conspiracism offers middle-aged men a sense of revitalization and adventure. In some ways it offers an even more complete escape than the proverbial mistress and sports car.” When is it ok to take a psychological stance? • If you already know that a person is delusional, then you shouldn’t treat them as an authority (e.g. a reliable witness). • If a person holds a view that seems obviously crazy, then assume a medical cause? • What if the person claims to have evidence for their strange view? Should you look at it? • In the first Terminator movie, a soldier (Kyle Reese) is sent back in time to save a woman (Sarah Connor) from being murdered by a robotic assassin who appears human. • There’s a scene where Reese is in police custody, explaining his story to a psychologist. • What does the psychologist conclude? What should he conclude? SILBERMAN: So. You're a soldier. Fighting for whom? REESE: With the One Thirty Second under Perry, from '21 to '27– SILBERMAN: (interrupting) The year 2027? REESE: That’s right. Then I was assigned Recon/ Security, last two years, under John Connor. SILBERMAN: And who was the enemy? REESE: SKYNET. A computer defense system built for SAC-NORAD by Cyber Dynamics.