1.Some people believe that the World Trade Center Collapse of September 11, 2001 was caused, not by foreign terrorists, but by high-ranking American officials. The plotters, the story goes, wanted to make sure that the buildings fell (because plane strikes alone wouldn’t accomplish their objectives?) and so brought down the towers via pre-arranged, controlled demolitions. This explanation has several flaws. Which of the following accuses the explanation of being unfalsifiable?

a. There is no real motive for such an attack. The conspiratorial explanation is that the attacks were a pretext for war. Generally, war is undesirable for political leaders and furthermore there has long been a precedent for the commitment of American forces without any prior attack on the U.S.

b. The thermite that was supposedly used to bring down the towers leaves not trace. It would be impossible to discover that thermite had not been used since there is no method of detecting it. This is a demerit of the conspiracy, rather than a merit.

c. The conspiracy theory is heavily reliant on eyewitness testimony. Some people at the scene claim to have heard explosions when the towers came down. It seems to be a mistake to rely on the impressions of onlookers in such a hectic situation.

d. The conspiracy theory is incredibly complex. It would involve thousands of people at all levels of government being knowingly involved in a great evil, and it would further require that no one involved would admit to involvement even after seeing the devastating harm caused by their actions. The official explanation can much more simply account for the data.

2.The argument following was first given by people who sell shark cartilage as a cancer treatment: No one has ever discovered a shark with cancer, so sharks do not get cancer.  Which of the following responses is the best criticism of the form (reliability or strength) of that argument?

a. Because the authors of the argument are an interested party, the argument is subject to a legitimate ad hominem criticism.

b. There are in fact many discoveries of sharks with cancer. A simple google search will reveal as much.

c. Because of their habitat and ferocity study of live sharks is limited. Furthermore, because of their divergent goals, those who routinely capture sharks do not search them for tumors. So, even if sharks did get cancer we wouldn’t expect to know about it.

d. Even if sharks don’t get cancer, that provides no evidence that ingesting shark cartilage is therapeutic as a cancer treatment.

3.Which of the following arguments is an appeal to ignorance?

a.Psychics typically agree that if you were born when mars was afflicting Neptune then you are more likely to have psychic ability. So, that is probably true.

b.People who are raised by wolves are ignorant of social customs. Since they couldn’t know any better they are excused for being rude or boorish.

c.There isn’t a single good reason to think that any school shootings have been staged. So, even though the conspiracy theorists resurrect the idea without proof, none were faked.

d. Some political candidates succeed by pandering to racists. So, that kind of appealing to the ignorant is (ironically) an appeal to ignorance.

4.Consider the simple argument:

Whenever I’m well rested, I do better on exams than average, whereas when I am not well rested, I do worse. So I think resting well helps me do better on exams. 

Which of the following would be the best criticism of the reliability or strength of the argument?

a.There is a plausible mechanism between resting well and cognitive (exam) performance.

b.You are an unusual test taker with respect to being well-rested.

c. If there were evidence that resting impacted testing then there would be evidence of it.

d. When you are well prepared for an exam early you are able to rest longer before it.

5.What the best criticism of the following argument?

Look we all agree that Bruce is an honest person, who always tells the truth. So when Bruce says he saw extraterrestrials land on Glenwood Avenue, he was telling the truth. Therefore it must be true that there were extraterrestrials landing on Glenwood Avenue.

a.Because he is obsessively intrigued with aliens, Bruce is an interested party.

b.Because of the difficulty in gaining knowledge of alien landings, Bruce is not an expert on them.

c.There are relevant dissimilarities between telling the truth and being correct about alien visits.

d. There are not enough objects under comparison; more sightings would improve the analogy.