Critical ThinkingCritical Thinking

CSCI 327

Many examples stolen from"Ethics and Computing"

by Kevin Bowyer

Q: What does critical thinking have to do with ethics or the social implications of computing?

A: Morally difficult situations are difficult precisely because it is difficult to reason clearly about them.

Structuring an ArgumentSince premise 1, and

premise 2, …

Therefore conclusion

A valid argument:

1. each premise is true,

2. each premise is relevant to the issue at hand,

3. the collection of premises establishes that the conclusion is true.

Common Critical Thinking Errors1. Errors arising from ambiguity2. Circular Arguments3. Use of Unwarranted Assumptions4. Fallacies involving missing evidence5. Incorrectly identified causation6. Premises irrelevant to stated conclusion7. Appeals to emotion / authority8. Diversion from the Main Point9. Incorrect Inference

Errors Arising from Ambiguity Three computers are on a table.

Someone points to one and says "I seen that one fail frequently." We assume the other two do not fail frequently.

It is ambiguous as to whether the other two have been seen to fail frequently.

Circular ArgumentsSince The criteria for patentability are

originality, novelty, utility, and nonobviousness, and

My invention is original, novel, useful, and non-obvious

Therefore My invention deserves to be patented.

The second premise is just a restatement of the conclusion.

Unwarranted AssumptionsSince Bob is a good programmer

Joe is a good programmer

Sue is a good programmer

Therefore Bob, Joe, and Sue will make a good development team.

We are assuming

1. they will work well together

2. they have all the other non-programming skills necessary

Unwarranted AssumptionsSince Bob thinks the code is fine.

Sue thinks debugging needs another 2 weeks.

Therefore We should test for 1 more week.

We are assuming

1. Bob and Sue are at each end of the possibilities

2. averaging estimates is a good idea

Fallacies Involving Missing Evidence

Since Testing revealed no bugs.

Therefore The code is bug free.

What evidence is missing?

Fallacies Involving Missing EvidenceSince The Software Industry has never had

look-and-feel copyrights

The software industry has done fine.

Therefore The software industry doesn't need these copyrights.

Where is the evidence that the two premises are related?

From the parallel universe where the software industry did have such copyrights?

Premises Irrelevant to Conclusion

Since Bob thinks the group should be re-organized.

Bob is frequently late to work.

Therefore We should not consider Bob's reorganization proposal.

Irrelevant Appeal to AuthoritySince A survey was taken at a conference of

interface designers

Interface designers don't want look-and-feel to be copyrightable.

Therefore Look-and-feel should not be copyrighted.

- Why are designers legal experts?

- Tell me more about the survey.

Incorrect Deductive Inference

Since employees using bad passwords is a security problem

our employees use good passwords

Therefore We have no security problems.

Are You Aware of the Dangers of Dihydrogen Monoxide?

Each year, Dihydrogen Monoxide (DHMO) is a known causative component in many thousands of deaths and is a major contributor to millions upon millions of dollars in damage to property and the environment. Some of the known perils include:

- Prolonged exposure to solid DHMO causes severe tissue damage- Found in biopsies of pre-cancerous tumors and lesions- DHMO is a major component of acid rain- Contributes to soil erosion- many, many more ... 

True Story In 1999, a Harvard technician discovered

pornography on a PC used by the Dean of the Harvard School of Divinity.

The porn was explicit, but not illegal. The dean resigned.

Should the tech have reported the incident?

more info… The work was done on a PC in the Dean's

home.

The home is owned by Harvard.

The PC was owned by Harvard.

The faculty handbook prohibits inappropriate material on university machines.

The work was to install a larger hard drive.

Quote from Alan Dershowitz

What the dean chooses to do privately is his own business and only becomes the university's concern if it is illegal. As long as it is done in private and doesn't hurt anyone, it is not the school's business.

In-Class Writing Assignment #1 Write at least one page (≈ 250 words) on either question 1 or 2. Write clearly! Grade based on

clarity of your argument, correct use of moral theories or critical thinking, readability, grammar, etc. (minor for this assignment)

Question 1:Show why Dershowitz's argument is invalid.Question 2:Do techs have a moral obligation to report such

incidents? Using one or more theories discussed on Tuesday, explain why or why not?