2008 Fall Quiz with answers

Here's a list of all the valid arguments with appraisals of their soundness. I expected students to recognize the first five valid arguments in this list of 8. Doing so and getting everything else right would have resulted in 100%. Students who saw the other three valid arguments and correctly judged them to be unsound could have earned as much as 24% of extra credit.

a. If a contract is signed voluntarily, then it should be legally binding.

k. William Stern and Mary Beth Whitehead signed the contract in the Baby-M case voluntarily.

therefore: m. The contract in the Baby-M case should be legally binding.

CLEARLY UNSOUND a is obviously false.

**************

b. If a contract is signed by competent individuals, then it should be legally binding.

j. William Stern and Mary Beth Whitehead, the signers of the contract in the Baby-M case, are competent.

therefore: m. The contract in the Baby-M case should be legally binding.

CLEARLY UNSOUND b is obviously false

************

c. If a contract does not call for any actions that ought to be illegal, then it should be legally binding.

h. The contract in the Baby-M case does not call for actions that ought to be illegal.

therefore: m. The contract in the Baby-M case should be legally binding.

CLEARLY UNSOUND c is obviously false

************

d. If a contract is signed voluntarily by competent individuals and does not call for actions that ought to be illegal, and its enforcement would violate no inalienable rights, then it should be legally binding.

h. The contract in the Baby-M case does not call for actions that ought to be illegal.

j. William Stern and Mary Beth Whitehead, the signers of the contract in the Baby-M case, are competent.

k. William Stern and Mary Beth Whitehead signed the contract in the Baby-M case voluntarily.

l. Enforcing the terms of the contract in the Baby-M case violates no inalienable rights.

therefore: m. The contract in the Baby-M case should be legally binding.

I believe this argument is unsound, but it's unsoundness is not obvious, nor is it obvious whether it is controversial whether it is unsound. So we gave credit for any answer here.

***********

g. If a contract calls for actions that ought to be illegal, then it should not be legally binding.

i The contract in the Baby-M case calls for actions that ought to be illegal.

therefore

n. The contract in the Baby-M case should not be legally binding.

CONTROVERSIAL g is clearly true, but i is controversial, so the soundness is controversial.

***********

THE VALIDITY OF THE NEXT THREE ARGUMENTS IS HARDER TO SEE, AND WILL BE EXPLAINED IN LECTURE. I DIDN'T EXPECT STUDENTS TO SPOT THESE. THE EASIEST WAY TO SEE THAT THESE ARE VALID IS TO PICTURE WHAT THE PREMISES AND CONCLUSION SAY. FOR EXAMPLE, A SAYS THAT THE SET OF ALL CONTRACTS THAT ARE SIGNED VOLUNTARILY IS CONTAINED IN THE SET OF ALL LEGALLY BINDING CONTRACTS. SINCE THE SET OF ALL CONTRACTS THAT ARE SIGNED VOLUNTARILY BY COMPETENT INDIVIDUALS AND THT DO NOT CALL FOR ACTIONS THAT OUGHT TO BE ILLEGAL MUST BE CONTAINED IN THE SET OF ALL CONTRACTS THAT ARE SIGNED VOLUNTARILY, (A) IMPLIES THAT IT MUST ALSO BE CONTAINED IN THE SET OF ALL CONTRACTS THAT ARE LEGALLY BINDING. SO IT IS IMPOSSIBLE FOR (A) TO BE TRUE AND FOR (D) TO BE FALSE.

a. If a contract is signed voluntarily, then it should be legally binding.

therefore d. If a contract is signed voluntarily by competent individuals and does not call for actions that ought to be illegal, and its enforcement would violate no inalienable rights, then it should be legally binding.

CLEARLY UNSOUND because a is obviously false

*********

b. If a contract is signed by competent individuals, then it should be legally binding.

CLEARLY UNSOUND because b is obviously false

*************

c. If a contract does not call for any actions that ought to be illegal, then it should be legally binding.

CLEARLY UNSOUND because c is obviously false

Part II (30 points): Reformulate the following passage as a logically valid argument with numbered premises and a conclusion. Do the best that you can to capture what the author of the passage has in mind: "People get out of contracts all the time, especially concerning emotional things. So it is absurd to maintain that a contract to give up a child should be legally enforceable." In what ways is your reformulation superior to the original passage?

Here's one possibility:

1. If a contract concerns emotional things, then it is not legally enforceable.

2. Surrogate motherhood contracts concern emotional things.

3. Surrogate motherhood contracts are not legally enforceable.

Such a reconstruction is clearer than the passage and reveals problems. First of all, "getting out of a contract" is different than the contract not being legally enforceable, and there is no way to reach a conclusion concerning whether surrogate motherhood contracts are legally enforceable from a premise about whether people "get out of contracts." But rephrasing the general claim in the passage as premise 1 makes it obvious that the argument is unsound.

Finally, for your reference, here are the directions for Part I of the quiz:

Part I of this quiz will make use of the following list of fourteen statements:

If a contract is signed voluntarily, then it should be legally binding.
If a contract is signed by competent individuals, then it should be legally binding.
If a contract does not call for any actions that ought to be illegal, then it should be legally binding.
If a contract is signed voluntarily by competent individuals and does not call for actions that ought to be illegal, and its enforcement would violate no inalienable rights, then it should be legally binding.
If a contract is not signed voluntarily, then it should not be legally binding.
If a contract is not signed by competent individuals, then it should not be legally binding.
If a contract calls for actions that ought to be illegal, then it should not be legally binding.
The surrogate motherhood contract in the Baby-M case does not call for actions that ought to be illegal.
The surrogate motherhood contract in the Baby-M case calls for actions that ought to be illegal.
William Stern and Mary Beth Whitehead, the signers of the contract in the Baby-M case, are competent.
William Stern and Mary Beth Whitehead signed the contract in the Baby-M case voluntarily.
Enforcing the terms of the contract in the Baby-M case violates no inalienable rights.
The contract in the Baby-M case should be legally binding.
The contract in the Baby-M case should not be legally binding.

A. Using only statements from the list, construct as many non-trivial and non-redundantvalid arguments as you can. By a "trivial argument" I mean an argument in which one of the premises is identical with the conclusion – that is an argument such as: (1) If a contract is signed voluntarily, then it should be legally binding (premise) therefore (2) If a contract is signed voluntarily, then it should be legally binding (conclusion). By a redundant valid argument I mean a valid argument that contains more premises than are needed to derive the conclusion. Write out fully in your blue book each of the non-trivial and non-redundant arguments you identify. (15 points each for the first three you identify and then 5 points each for each additional non-trivial and non-redundant valid argument. A 10 point penalty for each argument you write down that is invalid or redundant.)

B. In each case indicate whether the argument you have written down is clearly sound, clearly unsound, or whether it is controversial whether it is sound or unsound. (3 points for each correct answer)