#1 – Examine the argument from analogy in the following paragraph. Identify the elements in the structure of the argument: A and B (the two things being compared), P (the property attributed to B in the conclusion), and S (the property that makes A and B similar). If the latter property is not stated explicitly, try to find a plausible candidate. Work up a table of similarities and differences between the cases being compared. Is the analogy strong (the differences are minor and the similarities are deep) or is it weak (there are relevant differences that block the comparison)? Support your evaluation.

For someone who has created a work of art, a book, a new discovery or idea, the creation is like a child. So it is not surprising that creators feel intensely protective about their creations.

#2 –Perhaps the most famous argument by analogy is the ‘argument from design’ used to defend the existence of God. The passages following are from a work by the 18th century philosopher David Hume; the second is a counter analogy to the argument. Create a table of similarities and differences for each argument. Evaluate the two arguments.

A. “Look around the world: Contemplate the whole and every part of it: You will find it to be nothing but one great machine, subdivided into an infinite number of lesser machines which again admit of subdivisions to a degree beyond what human senses and faculties can trace and explain. All these various machines, and even their most minute parts, are adjusted to each other with an accuracy which ravishes into admiration all men who have ever contemplated them. The curious adapting of means to ends, throughout all nature, resembles exactly, though it much exceeds, the productions of human contrivance — of human design, thought, wisdom and intelligence. Since therefore the effects resemble each other, we are led to infer, by all the rules of analogy, that the causes also resemble, and that the Author of Nature is somewhat similar to the mind of man, though possessed of much larger faculties, proportioned to the grandeur of the work which he has executed.”

B. “Now, if we survey the universe, so far as it falls under our knowledge, it bears a great resemblance to an animal or organized body, and seems actuated with a like principle of life and motion. A continual circulation of matter in it produces no disorder; a continual waste in every part is incessantly repaired; the closest sympathy is perceived throughout the entire system; and each part or member, in performing its proper offices, operates both to its own preservation and to that of the whole. The world, therefore, I infer, is an animal; and the Deity is the soul of the world, actuating it, and actuated by it.” [David Hume, Dialogues Concerning Natural Religion]

STATISTICAL GENERALIZATIONS

#3. Identify potential biases and other problems in the following generalization.

Road and Track magazine polls its readers to find out what percentage of the population favors increased speed limits on interstate highways.

#4 The two opinion polls below were conducted at the same time by reputable pollsters, about the same proposed tax increase. What differences between the polls might explain the different results?

1. Q: As you may know, the tax cuts passed into law when George W. Bush was president are set to expire this year. Unless a new bill is passed, federal income tax rates will rise to the level they were when those cuts were enacted. Which of the following statements comes closest to your view?

— Those tax cuts should continue for all Americans. 31%

— Those tax cuts should continue for families that make

less than $250,000/year, but taxes should rise to the

previous level for families that make more than that. 51%

— Taxes should rise to the previous level for all Americans

regardless of how much money they make. 18%

2. Q: As you may know, the tax cuts passed during George W. Bush’s administration lowered taxes by reducing the maximum tax rate for all Americans. These tax cuts are set to expire at the end of 2010, meaning tax rates would go back to what they were before the Bush tax cuts. Congress is currently considering whether to let these tax cuts expire or extend them. Which of the following comes closest to your own view on what action Congress should take?

— Extend the tax cuts for all Americans. 49%

— Let the tax cuts expire only for people who earn

more than $200,000/yr. 31%

— Let the tax cuts expire for all Americans. 15%