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1

Describe the difference and relationship between deduction and induction (short answer).

Deductive arguments are those in which the conclusion follows with logical necessity from the premises. Inductive arguments provide only probable, but never logically certain justification of their conclusions. The truth value of the content of an inductive argument always determines whether it is good or bad, whereas a deductive argument is perfectly valid if its form is correct, regardless of the content.

2

What is the definition of a syllogism?

A form of reasoning where a conclusion is drawn from two premises which each share a term in the conclusion, and a common middle term not present in the conclusion.

3

What is the correct form of a categorical syllogism?

The Middle Term (M) must be in the two premises. The conclusion’s predicate (P) must be in the first premise, and the conclusion’s subject (S) must be in the second premise.

4

Is the following hypothetical syllogism valid or invalid?
Either it will rain or it will snow. It will not snow. Therefore, it will rain.

Valid

5

Is the following hypothetical syllogism valid or invalid?

Either God or nature causes disasters. Nature causes disasters. Therefore, God does not.

Invalid – The second proposition must be in the negative sense and the conclusion positive. A or B. Not B. Therefore, A.

6

Is the following hypothetical syllogism valid or invalid?

You must be either a liar or a fool. You’re not a fool, so you must be a liar.

Valid

7

Is the following hypothetical syllogism valid or invalid?

Either the professor’s theory of general insanity is true or I’m insane. But the professor’s theory is not true. Therefore, I am not insane.

Invalid – The conclusion must be positive.

8

Use the counterexample method to determine the validity of this categorical syllogism:

All squirrels are animals
Some wombats are not squirrels
Therefore, some wombats are not animals

All men are human
Some boys are not men
Therefore, some boys are not human

9

Use the counterexample method to determine the validity of this categorical syllogism:

All tigers are mammals
All tigers are animals
Therefore, all animals are mammals

All circles are round
All circles are shapes
Therefore, all shapes are round

10

Use the counterexample method to determine the validity of this categorical syllogism:

No fish are mammals
Some dogs are not fish
Therefore, some dogs are mammals

No pedestrians are cars
Some skateboarders are not pedestrians
Therefore, some skateboarders are cars

11

What are the five rules used to determine the validity of a categorical syllogism?

1. The middle term must be distributed at least once.
2. If a term is distributed in the conclusion, then it must be distributed in a premise.
3. Two negative premises are not allowed.
4. A negative premise requires a negative conclusion and vice versa.
5. If both premises are universal, the conclusion cannot be particular.
If and argument passes rules 1-4 it is conditionally valid.
If an argument passes all 5 rules it is unconditionally valid.

12

Identify whether the subject (S) or predicate (P) is distributed for each of the A E I O categorical propositions.

1. All S is P (S is distributed.)
2. No S is P (S and P are distributed.)
3. Some S is P (Nothing is distributed.)
4. Some S is not P (P is distributed.)

13

Use the five rules to determine the validity of this categorical syllogism:

All neutron stars are things that produce intense gravity.
All neutron stars are extremely dense objects.
Therefore, all extremely dense objects are things that produce intense gravity.

Invalid because it breaks rule #2.

14

Use the five rules to determine the validity of this categorical syllogism:

All ozone molecules are good absorbers of ultraviolet rays.
All ozone molecules are things destroyed by chlorine.
Therefore, some things destroyed by chlorine are good absorbers of ultraviolet
rays.

Conditionally valid because it only breaks rule #5.

15

Use the five rules to determine the validity of this categorical syllogism:

No insects that eat mosquitoes are insects that should be killed.
All dragonflies are insects that eat mosquitoes.
Therefore, no dragonflies are insects that should be killed.

Valid

16

Use the five rules to determine the validity of this categorical syllogism. Put it in standard form first:

No illegal aliens are people who have a right to welfare payments, and some migrant workers are illegal aliens. Thus, some people who have a right to welfare payments are migrant workers.

No illegal aliens are people who have a right to welfare payments.
Some migrant workers are illegal aliens.
Therefore, some people who have a right to welfare payments are migrant workers.

invalid because it breaks rule #4.

17

What is the difference between rationalism and empiricism?

Rationalism is an epistemology that requires certainty in order to have knowledge.
Empiricism is an epistemology that argues that the only reliable source of knowledge is pure experience.

18

Describe the flaws of foundationalism.

Foundationalism is a theory of knowledge that requires absolute certainty for all justifications.
Foundationalist philosophers believe that their assumptions are true and they can and should prove it.
Aristotelians realists believe that assumptions do not need to be proven, not that assumptions are bad, but you have to start with the right, common sense assumptions.
Human fallibility must be acknowledged when it comes to assumptions.
Aristotelians argue that the only legitimate goal of epistemology is to explain how we know, not prove that we know.

19

Is the following an inductive generalizations, argument from analogy, and causal argument?

Jim’s Subaru has a diesel engine, 5 speed transmission, and radial tires. It gets 50 miles per gallon. Therefore, my new Subaru with a diesel engine, 5 speed transmission, and radial tires will get 50mpg.

Argument from analogy

20

Is the following an inductive generalizations, argument from analogy, and causal argument?

The sun rose in the east on June 1, 1900, June 2, June 3, June 4, and so on. Therefore, the sun always rises in the east.

Inductive generalization

21

Is the following an inductive generalizations, argument from analogy, and causal argument?

The way Frank is staggering out of a bar leads me to believe he is drunk.

Effect to cause causal argument

22

Is the following an inductive generalizations, argument from analogy, and causal argument?

Given how much Frank drank tonight, he will be drunk and sick.

Cause to effect causal argument

23

Identify the necessary and sufficient conditions:

Being a bachelor is a ________ condition for being a male, and being a male is a ________ condition for being a bachelor.

Being a bachelor is a sufficient condition for being a male, and being a male is a necessary condition for being a bachelor.

24

Identify the necessary and sufficient conditions:

Being a resident of Atlanta is a ________ condition for being a resident of Georgia, and being a resident of Georgia is a ________ condition for being a resident of Atlanta.

Being a resident of Atlanta is a sufficient condition for being a resident of Georgia, and being a resident of Georgia is a necessary condition for being a resident of Atlanta.

25

Identify the necessary and sufficient conditions:

Completing most of the assignments is a ________ condition for passing the course.

Completing most of the assignments is a necessary condition for passing the course.

26

Identify the necessary and sufficient conditions:

Winning the division is a ________ condition for the Braves to qualify for the playoffs.

Winning the division is a necessary condition for the Braves to qualify for the playoffs.

27

Identify the necessary and sufficient conditions:

Being a natural born citizen is a ________ condition for being President of the United States, and being President of the United States is a ________ condition for being a natural born citizen.

Being a natural born citizen is a necessary condition for being President of the United States, and being President of the United States is a sufficient condition for being a natural born citizen.

28

Explain the fallacy of Cartesian Doubt.

The Cartesian doubt fallacy is when an inductive argument is held to the standards of a deductive argument. For instance, saying that “Jim’s 2016 Toyota Prius gets on average 50mpg, but my exactly same 2016 Toyota Prius may not because some cars are lemons,” is irrelevant. Inductive arguments only need to have some degree of probability, not a deduced certainty.

29

Identify the fallacy in this inductive argument:

I know Sam was obviously drunk and in a fit of rage when he asked for his shotgun. But still Dave promised to return the gun whenever Sam wanted it back. So it was wrong for him to lie about losing the key to the trunk in which he locked the shotgun.

Accident – A rule or generalization has been mechanically levied against an exceptional case.

30

Identify the fallacy in this inductive argument:

Obviously God doesn’t exist. Nobody can prove that he does.

Appeal to Ignorance – Nobody can prove otherwise, so it must be true/false.