Argument Analysis

Extended arguments Whether an argument is deductive or inductive, we can organize its premises and conclusion in a form of flowchart in order to understand their inferential relationship. In order to do this, we need to understand the content of each statement.

Methods 1. Use numerals to label various statements consecutively. 2. Use arrows to represent the inferential links. 3. Useless statements need not be labeled.

Vertical pattern Example 1. The HK Government must deal with the high unemployment rate. 2. High unemployment will cause serious crimes. 2 1

Horizontal pattern 2 3 4 1 Example 1. Gambling must be banned. 2 3 4 1 Example 1. Gambling must be banned. 2. Gambling encourages illegal activities. 3. Gamblers can become addictive. 4. There are more family disharmony in a gambling family.

Conjoint premises Example 1. Eliminating exam from our secondary schools must be coupled with an effort to ensure a fair continuous assessment. 2. Teachers have to evaluate the performance of students. 3. Without exam, teachers have no way to evaluate their students’ performance unless there is a fair continuous assessment of it.

Without (2), (3) by itself cannot support (1). (2) and (3) have to work together in order to support (1).

Conjoint premises 2 3 1

Multiple conclusions 1. Lacking interest and time are two of the primary causes of poor school performance. Therefore: 2. To improve school performance, we must ignite students’ interest. And 3. We must also give students enough time.

Multiple conclusion 1 1 2 3

Argument Exemplar 1 Government mandates for zero-emission vehicles won’t work because only electric cars qualify as zero-emission vehicles, and electric cars won’t sell. They are too expensive, their range of operation too limited, and recharging facilities are not generally available.

Argument Exemplar 2 (1) Eating meat cannot be immoral. First of all, (2) we cannot survive without eating meat. Second, (3) Humans have eaten meat for thousands of years, and (4) following what our ancestors did cannot be immoral. Third, (5) no one would say that a lion is immoral based on the fact that it eats other animals. Finally, (6) eating meat does not contribute to the world’s famine as some people argue. This is because (7) the world’s famine is caused by the poverty of developing countries, and (8) eating meat is not related to their poverty.

What is a good argument? Condition 1: The premises are true or highly plausible. Consider this argument: Homosexuality is unnatural. Therefore, it is immoral. If “natural” means “common among animals,” the premise is false because more than 1000 species have found to have homosexual behavior. If “natural” means “common among humans,” the premise is true. However, this will render the implicit premise false (see next slide).

Condition 2: The argument is deductively valid or inductively strong. The above argument is valid if we add this implicit premise: All unnatural behaviors are immoral. Given that “natural” means “common among humans,” this implicit premise is patently false. E.g.: Studying Latin is unnatural but no one thinks that it is immoral.

Condition 3: The premises are not question begging. i.e., The conclusion is not one of the premises. Compare this argument: Only clever people can see the King’s new coat because fools are not able to see it.