Answers to Practice Quiz #2

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Rafe Carr
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1 Philosophy 1104: Critical Thinking Answers to Practice Quiz #2 [Total: 50 marks] 1. In which of the following pairs of propositions does A provide conclusive evidence for B? Also say whether or not A provides at least some evidence, no matter how weak (i.e. say whether A is positively relevant to B). Write just Yes or No in each column provided. A B Conclusive evidence? Some evidence? (i) Fred just hit a hole-in-one Fred is a very good golfer No Yes (ii) I have between 4 and 6 eggs I have at least 3 eggs Yes (iii) I have at least 4 eggs I have 5 or more eggs No Yes (iv) It s not the case that every politician is corrupt. Every politician is honest No Yes (v) Janet likes listening to Jazz Vancouver is west of Calgary No No (vi) Simpson is a world-class skier Simpson is a non-smoker No Yes (vii) We re having fish for supper We re having trout for supper No Yes (viii) Qin s theory is rejected by all relevant scientific authorities Qin s theory is false No Yes (ix) Sally is a Catholic Sally has eight children No Yes (x) Ali stabbed a man in Vernon, B.C. in Ali first entered Canada in No No [1 mark each] In rows where you say yes in the first column, you should of course say yes in the second as well! Or just leave the second column blank, if you prefer.

2 2. Each of the following definitions is flawed in some way (each in just one way, I think, or at least one main one). Diagnose each definition as circular, too narrow, too broad, or loaded. Give two such diagnoses if you want. [2 marks each] (i) An economist is someone who uses a lot of statistics. too broad (ii) A mammal is defined a four-legged furry animal that feeds its young on milk. too narrow (e.g. dolphin) (iii) An atheist is someone who fails to acknowledge God s existence. loaded (iv) By matter I mean the stuff that material objects are made of. circular 3. Oh why do you insist on finishing your master s degree? You re so obstinate! -- I m not obstinate, I m determined! Is this disagreement merely verbal? If not, then describe the underlying substantial disagreement, saying whether it is factual, or interpretative, or evaluative. There seems to be an underlying evaluative disagreement here. Is it a good idea to finish the master s degree? [3 marks] 4. Dave and I were at odds about whether foetuses are human beings. I pointed out that their brains are very undeveloped, so they re far less intelligent than fully-grown dogs. They re incapable of making moral choices. But Dave replied that a DNA test would reveal a foetus to be human at any stage. What are they grasshoppers? he snorted. Explain how this dispute might, at least, be merely verbal. Dave is apparently using human being to refer merely to the human species, whereas the other speaker is using human being to mean a person with moral rights. [3 marks] 2

3 5. Identify the following substantial disagreements as factual, interpretative or evaluative. [2 marks each] (i) I don t like that knocking sound from your engine. I think you have a cracked piston. -- No, don t worry. It s just a worn lifter. interpretative (what s the cause?) (ii) I can t believe that you still go rock climbing, now that you have kids. It s totally unnecessary. What if you fell down a cliff and died? You need to keep yourself safe. -- Rubbish. Rock climbing is not unsafe by any means. I agree that there s some danger, like there is with everything, but the risk is moderate and well worth it. evaluative (is it the right thing to do?) (iii) You ll never believe what Rachel said about my painting. She said it was interesting, and I never seen anything like it before! She loves it! -- Actually, it sounds to me as if she didn t like it, but didn t want to hurt your feelings. _interpretative (what caused her to say those things?) (iv) It s like Herbert Hoover said, The business of America is business. -- Actually it was Calvin Coolidge who said that. factual 6. Identify the following sentences as expressing either approximate/vague beliefs or probable beliefs, or both. Write vague, probable, or both. [1 mark each] (i) The likely outcome is that you ll get fined $1000. probable (ii) I think Alice is now teaching physics at BCIT. probable (iii) Next year s PSA conference is expected to be held in Denver. probable (iv) Alice got a new job somewhere. vague (v) As far as I know, these grey chunks are a kind of meat. both 3

4 7. Suppose you are asked: How much does this child weigh?, and the correct (but unknown) answer is 42 pounds. (i) Give an example of a vague, but true, answer to the question. He weighs between 10 and 70 pounds [1 mark] (ii) Give an example of a precise, but false, answer to the question. He weighs 45 pounds [1 mark] (iii) Can a false statement be approximately true? If so, then give an example. Otherwise explain why not. Yes, see part (ii) [1 mark] (iv) Suppose you have to decide whether to carry the child on your back during a day hike. (It would be unfortunate to leave the child at home, if he s light enough to be carried, but even worse to bring the child, if he turns out to be too heavy.) How might a false opinion about the child s weight be more useful than a true one in this situation? If the false answer is approximately true, as in part (ii), then it s as good as knowing the exact truth in the context. Moreover, the true answer in part (i) is too vague to tell us what we should do here. [2 marks] 8. Scan through the attached article Inferior Design, and highlight every argument from authority that Dawkins uses to attack Behe s views. (If you don t have a highlighter pen then just draw a loop around the relevant text.) [2 marks each = 8 total] July 1, 2007 Inferior Design By RICHARD DAWKINS I had expected to be as irritated by Michael Behe s second book as by his first. I had not expected to feel sorry for him. The first Darwin s Black Box (1996), which purported to make the scientific case for intelligent design was enlivened by a spark of conviction, however misguided. The second is the book of a man who has given up. Trapped along a false path of his own rather unintelligent design, Behe has left himself no escape. Poster boy of creationists everywhere, he has cut himself adrift from the world of real science. And real science, in the shape of his own department of biological sciences at Lehigh University, has publicly disowned him, via a remarkable disclaimer on its Web site: While we respect Prof. Behe s right to express his views, they are his alone and are in no way endorsed by the department. It is our collective position that intelligent design has no basis in science, has not been tested experimentally and should not be regarded as scientific. As the Chicago geneticist Jerry Coyne wrote recently, in a devastating review of Behe s work in The New Republic, it would be hard to find a precedent. 4

5 For a while, Behe built a nice little career on being a maverick. His colleagues might have disowned him, but they didn t receive flattering invitations to speak all over the country and to write for The New York Times. Behe s name, and not theirs, crackled triumphantly around the memosphere. But things went wrong, especially at the famous 2005 trial where Judge John E. Jones III immortally summed up as breathtaking inanity the effort to introduce intelligent design into the school curriculum in Dover, Pa. After his humiliation in court, Behe the star witness for the creationist side might have wished to re-establish his scientific credentials and start over. Unfortunately, he had dug himself in too deep. He had to soldier on. The Edge of Evolution is the messy result, and it doesn t make for attractive reading. We now hear less about irreducible complexity, with good reason. In Darwin s Black Box, Behe simply asserted without justification that particular biological structures (like the bacterial flagellum, the tiny propeller by which bacteria swim) needed all their parts to be in place before they would work, and therefore could not have evolved incrementally. This style of argument remains as unconvincing as when Darwin himself anticipated it. It commits the logical error of arguing by default. Two rival theories, A and B, are set up. Theory A explains loads of facts and is supported by mountains of evidence. Theory B has no supporting evidence, nor is any attempt made to find any. Now a single little fact is discovered, which A allegedly can t explain. Without even asking whether B can explain it, the default conclusion is fallaciously drawn: B must be correct. Incidentally, further research usually reveals that A can explain the phenomenon after all: thus the biologist Kenneth R. Miller (a believing Christian who testified for the other side in the Dover trial) beautifully showed how the bacterial flagellar motor could evolve via known functional intermediates. Behe correctly dissects the Darwinian theory into three parts: descent with modification, natural selection and mutation. Descent with modification gives him no problems, nor does natural selection. They are trivial and modest notions, respectively. Do his creationist fans know that Behe accepts as trivial the fact that we are African apes, cousins of monkeys, descended from fish? The crucial passage in The Edge of Evolution is this: By far the most critical aspect of Darwin s multifaceted theory is the role of random mutation. Almost all of what is novel and important in Darwinian thought is concentrated in this third concept. What a bizarre thing to say! Leave aside the history: unacquainted with genetics, Darwin set no store by randomness. New variants might arise at random, or they might be acquired characteristics induced by food, for all Darwin knew. Far more important for Darwin was the nonrandom process whereby some survived but others perished. Natural selection is arguably the most momentous idea ever to occur to a human mind, because it alone as far as we know explains the elegant illusion of design that pervades the living kingdoms and explains, in passing, us. Whatever else it is, natural selection is not a modest idea, nor is descent with modification. But let s follow Behe down his solitary garden path and see where his overrating of random mutation leads him. He thinks there are not enough mutations to allow the full range of evolution we observe. There is an edge, beyond which God must step in to help. Selection of random mutation may explain the malarial parasite s resistance to chloroquine, but only because such micro-organisms have huge populations and short life cycles. A fortiori, for Behe, 5

6 evolution of large, complex creatures with smaller populations and longer generations will fail, starved of mutational raw materials. If mutation, rather than selection, really limited evolutionary change, this should be true for artificial no less than natural selection. Domestic breeding relies upon exactly the same pool of mutational variation as natural selection. Now, if you sought an experimental test of Behe s theory, what would you do? You d take a wild species, say a wolf that hunts caribou by long pursuit, and apply selection experimentally to see if you could breed, say, a dogged little wolf that chivies rabbits underground: let s call it a Jack Russell terrier. Or how about an adorable, fluffy pet wolf called, for the sake of argument, a Pekingese? Or a heavyset, thick-coated wolf, strong enough to carry a cask of brandy, that thrives in Alpine passes and might be named after one of them, the St. Bernard? Behe has to predict that you d wait till hell freezes over, but the necessary mutations would not be forthcoming. Your wolves would stubbornly remain unchanged. Dogs are a mathematical impossibility. Don t evade the point by protesting that dog breeding is a form of intelligent design. It is (kind of), but Behe, having lost the argument over irreducible complexity, is now in his desperation making a completely different claim: that mutations are too rare to permit significant evolutionary change anyway. From Newfies to Yorkies, from Weimaraners to water spaniels, from Dalmatians to dachshunds, as I incredulously close this book I seem to hear mocking barks and deep, baying howls of derision from 500 breeds of dogs every one descended from a timber wolf within a time frame so short as to seem, by geological standards, instantaneous. If correct, Behe s calculations would at a stroke confound generations of mathematical geneticists, who have repeatedly shown that evolutionary rates are not limited by mutation. Single-handedly, Behe is taking on Ronald Fisher, Sewall Wright, J. B. S. Haldane, Theodosius Dobzhansky, Richard Lewontin, John Maynard Smith and hundreds of their talented coworkers and intellectual descendants. Notwithstanding the inconvenient existence of dogs, cabbages and pouter pigeons, the entire corpus of mathematical genetics, from 1930 to today, is flat wrong. Michael Behe, the disowned biochemist of Lehigh University, is the only one who has done his sums right. You think? The best way to find out is for Behe to submit a mathematical paper to The Journal of Theoretical Biology, say, or The American Naturalist, whose editors would send it to qualified referees. They might liken Behe s error to the belief that you can t win a game of cards unless you have a perfect hand. But, not to second-guess the referees, my point is that Behe, as is normal at the grotesquely ill-named Discovery Institute (a tax-free charity, would you believe?), where he is a senior fellow, has bypassed the peer-review procedure altogether, gone over the heads of the scientists he once aspired to number among his peers, and appealed directly to a public that as he and his publisher know is not qualified to rumble him. 6

Behe interview transcript

Behe interview transcript David Marshall In late July, I interviewed maverick biologist Michael Behe by phone, at his office at Lehigh University. Behe is the author of Darwin s Black Box (Free Press,