cogency

Almost every known human carcinogen causes cancer in animals. Thus it is reasonable to expect that compounds that cause cancer in animals are also human carcinogens.

A deductive argument:

1. All Greeks are human beings.

2. All Athenians are Greeks.

3. Therefore, all Athenians are human beings.

An inductive argument:

1. X₁, X₂, X₃, . . . X_Charlie have red hair and hot tempers.

2. X_Dianehas red hair.

3. Therefore, (probably) Diane has a hot temper.

An inductive argument with a conclusion we know would be true:

1. X₁, X₂, X₃, . . . X_Charlie are both smokey and fiery.

2. X_my
houseis smokey.

3. Therefore, my house is fiery.

MORAL REASONING

Simple Case: Murder

Jennifer hits Michael over the head with a baseball bat.

Moral reasoning typically involves both factual and moral premises.

Fact: This action was a murder.

Moral principle or premise: Murder is wrong.

Conclusion: This action was wrong.

To justify the factual premise:

1. Murder is killing a human being with malice aforethought. (Definition)

2. Jennifer killed Michael. (Fact known by perception or another means)

3. Michael was human. (Fact)

4. Jennifer's act was premeditated and malicious. (Fact)

To justify the moral principle, we may argue from above or from below.

From below, we argue from instances:

· This murder was wrong.

· That murder was wrong.

· .

· Murder is wrong.

From above, we argue from broader principles: we need a moral theory. Often this takes the form of one fundamental moral principle from which everything else can be derived.

Ancient examples:

· Golden Rule (Confucius, Jaina ahimsa): What you would not want others to do unto you, do not do unto others.

· Golden Rule (Jesus): What you would want others to do unto you, do unto others.

· Virtue ethics: Act to become a virtuous person (e.g., to become a Bodhisattva, according to Mahayana Buddhism, a “superior person,” according to Confucius and Taoism, etc.)

Modern examples:

· Kant, the Categorical Imperative: Act so that the maxim of your action might be universal law. (Treat others as ends in themselves, not merely as means)

· Mill, the Principle of Utility: Maximize happiness.

· W. D. Ross, “best lights” (see below): weigh prima facie duties.

Argument from above:

1. Fundamental principle

2. Murder is [not loving, not something you would want to happen to you, not treating another as an end, not conducive to happiness, not conducive to becoming a Bodhisattva, ruled out by a duty]

3. Murder is wrong.

Formal Principle of Justice

Kant: Act so that the maxim of your action might be universal law.

Treat similar cases similarly, i.e., equivalently:

Universalize principles but judge on the basis only of morally relevant factors

What is morally relevant?

· Circumstances in which the action is done (Immediate, Historical)

· How the action is done

· The agent's state of mind: intentions (what did the agent mean to do?), motives (why did the agent mean to do it?)

· Consequences of the action

What kinds of factors are usually morally irrelevant?

A Pluralist (“Best Lights”) View of Ethical Reasoning

W. D. Ross’s list of prima facie duties, deriving from:

1. previous acts of my own: (a) duties of fidelity (promise-keeping) & (b) duties of reparation

2. previous acts of others: duties of gratitude

3. possibility of a distribution of pleasure or happiness: duties of justice

4. teleological duties: maximize the good: Ross calls these "duties of beneficence"

5. duties of self-improvement

6. duties to respect the rights of others and to refrain from injuring them (Ross thinks this is needed in addition to (4) )

The individual resolves conflicts of “pull” by weighing duties and acting by her/his “best lights.”