Chapter 4

Question 1

In logic we are concerned with evidence of truth in a proposition. this evidence is______

Answer 1

A conclusion

Question 2

The evidence in support of these conclusions consists of other propositions, which are termed _______

Answer 2

Premises

Question 3

In order to support a conclusion, one must use other propositions or ____.

Answer 3

Premises

Question 4

For each ______ we must identify the premises that provide the evidence for that ______[same as above]____ and those premises should be distinct propositions.

Answer 4

conclusion, conclusion

Question 5

A set of premises together with a conclusion is an _____

Answer 5

Argument

Question 6

In logic an argument is made up of what?

Answer 6

A set of premises (or other propositions that provide the evidence for a conclusion) and a conclusion

Question 7

In an argument the conclusion is ____ from the premises

Answer 7

Inferred

Question 8

In logic a synonym for argument is____

Answer 8

Inference

Question 9

Conclusion indicators include:

Answer 9

Thus
Therefore
So
Consequently 
As a result 
Which means that
Hence
Which means that
Which implies that

Question 10

Premise indicators include:

Answer 10

Since
Because
As
For
Given that
Assuming that
In as much as
The reason that
In view of the fact

Question 11

The author doesn’t just tell the reader what they think to be true, they also present _____ which are intended to convince the reader that it is true.

Answer 11

Reasons

Question 12

Examples in this chapter involve different types of reasoning, but they also illustrate a common pattern. In each case we are concerned with evidence for the truth of some proposition. In logic, this proposition is called a _____. The evidence in support of these _______ consists of other propositions called premises. Thus each of our examples involves the use of premises to support a ______.

Answer 12

this proposition is called a conclusion
…support of the conclusions
to support a conclusion

Question 13

Examples in this chapter involve different types of reasoning, but they also illustrate a common pattern. In each case we are concerned with evidence for the truth of some proposition. In logic, this proposition is called a conclusion. The evidence in support of these conclusions consists of other propositions called ______. Thus each of our examples involves the use of_______ to support a conclusions.

Answer 13

premises

Question 14

A set of premises together with a conclusion is called an ______.

Answer 14

argument

Question 15

In logic, an argument is a set of …..

Answer 15

a set of premises with a conclusion

Question 16

In everyday speech, argument is often used to mean a quarrel between two people. But it is also
used to mean…..

Answer 16

an appeal to evidence in support of a conclusion in logic

Question 17

______ means a set of propositions in which some propositions (the premises) are asserted as support or evidence for another (the conclusion).

Answer 17

Argument

Question 18

A conclusion is inferred from the ________. Thus an argument can also be described as an _____.

Answer 18

premises

inference

Question 19

We can think of the premises as the raw materials for an argument and the conclusion as the final product. To understand an argument, we need to know what happens in between—on the factory floor, so to speak. We need to analyze the inner workings of the argument, the individual steps that lead from premises to conclusion. Once we have analyzed the argument, we can go on to ______ it: Is it a good argument? Does it provide
a good reason to accept the conclusion?

Answer 19

evaluate it

Question 20

There are two main steps in reviewing an argument. They are…

Answer 20

analyzing and evaluating

Question 21

An _____ pointing from premise to conclusion represents a single step in reasoning—the relationship between a premise and the conclusion.

Answer 21

an arrow

Question 22

In some cases, the premises are _____ on one another: Two or more premises work together to make a single argument for a conclusion.

Answer 22

dependent

Question 23

In other cases, the premises are ______: They do not work together; each one offers a separate line of support for the conclusion.

Answer 23

independent

Question 24

When we put premises together in order to create an argument—meaning they are dependent on each other. We represent this fact by using a second symbol ____ , to join the premises.

Answer 24

the plus (+) sign

Question 25

When premises independently support the conclusion we would diagram the argument by using _____ to join each
premise to the conclusion separately.

Answer 25

arrows

Question 26

In an argument with independent premises, two (or more) arrows will converge on the conclusion. But can we have the opposite situation? Can we have arrows diverging
from a single premise to two or more different conclusions? That is, can a single face serve as evidence for more than one conclusion?

Answer 26

Certainly

Question 27

In everyday chinking, as well as in science and ocher academic subjects, we often find chains of ______

Answer 27

inferences (or arguments)

Question 28

For example, if someone opposes gun control on
the ground that it violates the right of self-defense, we might ask: Why assume people have such a right? The person might answer: Because people have a right to life,
and therefore have a right to defend it/themselves. So we have four propositions to deal with, which are

Answer 28

1. People have a right to life.
2. People have a right to defend their lives.
3. Gun control violates the right of self-defense.
4. The government should not restrict gun ownership.

Question 29

1. People have a right to life.
2. People have a right to defend their lives.
3. Gun control violates the right of self-defense.
4. The government should not restrict gun ownership.

How would this be diagrammed?

Answer 29

1 —–> 2+3 ——-> 4

Question 30

Strategy for diagramming arguments (or inferences):

1. An argument must have at least one ____ and one ____; use an arrow to represent the link between them .

Answer 30

at least one premise and one conclusion

Question 31

Strategy for diagramming arguments (or inferences):

1. An argument must have at least one premise and one conclusion; use an_____ to represent the link between them .

Answer 31

an arrow

Question 32

Strategy for diagramming arguments (or inferences):

2. A single conclusion may be supported by more than one_____; use a plus sign and a single arrow for dependent premises, convergent arrows for independent ones.

Answer 32

premise

Question 33

Strategy for diagramming arguments (or inferences):

2. A single conclusion may be supported by more than one premise; use a _____ and a single arrow for dependent premises, convergent _____ for independent ones.

Answer 33

use a plus sign (+)

convergent arrows for independent ones

Question 34

Strategy for diagramming arguments (or inferences):

3. A single premise may support more than one ______; draw divergent arrows.

Answer 34

conclusion

Question 35

Strategy for diagramming arguments (or inferences):

3. A single premise may support more than one conclusion; draw ______ _____.

Answer 35

divergent arrows

Question 36

Strategy for diagramming arguments (or inferences):

4. An argument may have more than one step, so that a given proposition can be both a conclusion (of one step) and a premise (of another step}; use ______ to represent each step, with the final conclusion on the bottom line.

Answer 36

separate arrows

Question 37

The basic standard to evaluation is that an _____ is good to the extent that it provides evidence for the truth of its conclusion.

Answer 37

argument

Question 38

The basic standard of evaluation is that an argument is good to the extent that it provides ______ for the truth of its conclusion.

Answer 38

evidence

Question 39

What is the goal to reasoning?

Answer 39

the goal of reasoning is to determine the truth or falsity of propositions that we are not in a position to verify directly by sense perception.

Question 40

To provide evidence for a conclusion, an argument must have two essential attributes.

First, its premises must be _____.

Answer 40

True

An argument is an attempt to establish the truth of a proposition by relating it to facts we already know. So we have to start from facts; false premises don’t prove anything.

Question 41

To provide evidence for a conclusion, an argument must have two essential attributes.

Second, the premises must be logically related to the conclusion in such a way that if the premises are true, the conclusion is likely to be ______ as well.

Answer 41

true as well.

In other words, it is not enough that the premises be true; they must also support the conclusion. They must provide evidence that the conclusion is true.

Question 42

Consider this argument:

(1) All fish breathe through gills, and (2) whales are fish. Therefore (3) whales breathe through gills.

Answer 42

Premise 2 is false. Nevertheless, the conclusion follows from the premises ; if both premises were true, the conclusion would have to be true as well.

Question 43

There are many types of arguments which are….

Answer 43

Inductive and deductive

Question 44

Deductive arguments….

Answer 44

A deductive argument is an argument that is intended by the arguer to be deductively valid, that is, to provide a guarantee of the truth of the conclusion provided that the argument’s premises are true. This point can be expressed also by saying that, in a deductive argument, the premises are intended to provide such strong support for the conclusion that, if the premises are true, then it would be impossible for the conclusion to be false.

Question 45

A _____ argument is an argument that is intended by the arguer to be _______ly valid, that is, to provide a guarantee of the truth of the conclusion provided that the argument’s premises are true. This point can be expressed also by saying that, in a ______ argument, the premises are intended to provide such strong support for the conclusion that, if the premises are true, then it would be impossible for the conclusion to be false.

Answer 45

Deductive
Deductively
Deductive

Question 46

An argument in which the premises do succeed in guaranteeing the conclusion is called a _____ or valid argument.

Answer 46

deductive

Question 47

Here is a valid ____ argument:

It’s sunny in Singapore. If it’s sunny in Singapore, then he won’t be carrying an umbrella. So, he won’t be carrying an umbrella.

Answer 47

deductive

Question 48

Here is a mildly strong ________ argument:

Every time I’ve walked by that dog, it hasn’t tried to bite me. So, the next time I walk by that dog it won’t try to bite me.

Answer 48

inductive

Question 49

An _______ argument is an argument that is intended by the arguer to be strong enough that, if the premises were to be true, then it would be unlikely that the conclusion is false. So, an ______ argument’s success or strength is a matter of degree.

Answer 49

inductive

Question 50

There is no standard term for a successful inductive argument, but this article uses the term “_____.” Inductive arguments that are not ______ are said to be weak; there is no sharp line between _____ and weak.

Answer 50

Strong

Question 51

Logicians often describe inductive arguments as _____. The conclusion ______ or goes beyond what the premises state

Answer 51

Ampliative

Amplifies

Question 52

Which of the following is an argument?

Select one:

a. The boss always rewards hard work, but punishes laziness.
b. He straightened his tie carefully, as he did every morning.
c. Since cheerleading is physically demanding, it should be considered a sport.
d. Amanda was able to buy a new car because she got a promotion at work.
e. Since the blizzard of 2002, it has never snowed in our town.

Answer 52

c. Since cheerleading is physically demanding, it should be considered a sport.

Question 53

Which of the following is an argument?
(I) It will probably rain tomorrow because a cold front is moving in.
(II) It rained yesterday because a cold front moved in.

Select one:

a. both I and II
b. only I
c. neither
d. there is not enough information to know
e. only II

Answer 53

b. only I

Question 54

Generalization is:

Select one:

a. interrupting while someone else is trying to explain an argument
b. applying a general rule to a particular case
c. drawing a conclusion without any evidence to support it
d. arguing in a vague way without specifying what you mean
e. drawing a conclusion about a class of things by observing a sample of the class

Answer 54

e. drawing a conclusion about a class of things by observing a sample of the class

Question 55

For which argument below are the premises dependent?

Select one:
a. Premises: The car stalled twice last week. The car has a malfunctioning headlight.
Conclusion: The car will need to go to the repair shop soon.

b. Premises: Sarah has very light skin. Sarah has blue eyes.
Conclusion: Sarah is of Northern European descent.

c. Premises: Penguins have feathers. Penguins have beaks.
Conclusion: Penguins are birds.

d. Premises: Bill always says hello. Bill has many friends.
Conclusion: Bill is very social.

e. Premises: Politics depends on morality. Morality depends on religion.
Conclusion: Politics depends on religion

Answer 55

e. Premises: Politics depends on morality. Morality depends on religion.
Conclusion: Politics depends on religion.

Question 56

Which of the following premises provides the strongest support for the conclusion that Harry is a lousy driver?

Select one:

a. Harry has poor vision and can’t tell the brake pedal from the accelerator.
b. Harry was involved in a major accident.
c. Harry failed driver’s ed three times.
d. Harry got a parking ticket.
e. Harry once dinged his door in a parking lot.

Answer 56

a. Harry has poor vision and can’t tell the brake pedal from the accelerator.

The observation that “Harry has poor vision and can’t tell the brake pedal from the accelerator” provides objective, direct, explicit evidence that Harry is not a good driver. Good vision (at least, non-poor vision) is necessary for good driving, and knowing how the pedals function is also necessary.

The fact that Harry was in an accident tells us very little about his driving. The accident could have been another driver’s fault.

The fact that Harry failed Driver’s Ed three times is not very informative, for it may have been a very bad teacher, Harry may have had other more important obligations during the course, etc.

Getting a parking ticket does not relate to Harry’s actual driving skill, and likewise for getting his door dinged in a parking lot.

Question 57

For which argument below are the premises independent?

Select one:
a. Premises: Spinach contains iron. This omelet contains spinach.
Conclusion: This omelet contains iron.

b. Premises: Laser eye surgery is getting cheaper. Cheaper goods have greater appeal.
Conclusion: Laser eye surgery is becoming more appealing.

c. Premises: The rule of law allows people to know the consequences of their actions. The rule of law is fair to all people.
Conclusion: The rule of law is a worthy idea.

d. Premises: Lagos is in Nigeria. Nigeria is in Africa.
Conclusion: Lagos is in Africa.

e. Premises: Japan has a thriving electronics industry. Any country with a thriving electronics industry is wealthy.
Conclusion: Japan is wealthy.

Answer 57

c. Premises: The rule of law allows people to know the consequences of their actions. The rule of law is fair to all people.
Conclusion: The rule of law is a worthy idea.

Question 58

If there are two strong arguments, can one be stronger than the other?

Select one:

a. No, because every argument is strong in its own way.
b. Yes, because one might have more importance.
c. No, because all arguments are equally strong.
d. No, because arguments can’t really be compared to each other.
e. Yes, because one might support its conclusion better.

Answer 58

e. Yes, because one might support its conclusion better.

Question 59

For which argument below are the premises independent?

Select one:
a. Premises: It is not safe to smoke around an oxygen tank. Your friend is smoking near that oxygen tank.
Conclusion: You should tell your friend to move away from the tank.

b. Premises: Yoga is very relaxing. Relaxation would improve my heart health.
Conclusion: Yoga would improve my heart health.

c. Premises: The newspaper should cover all important stories. The election is an important story.
Conclusion: The newspaper should cover the election.

d. Premises: The river’s water level is falling. Fish require a high water level.
Conclusion: The river’s fish are endangered.

e. Premises: My mother says I have a nice smile. My father says I have a nice smile.
Conclusion: I have a nice smile

Answer 59

e. Premises: My mother says I have a nice smile. My father says I have a nice smile.
Conclusion: I have a nice smile

Question 60

DEDUCTIVE ARGUMENT
The premises are an attempt to guarantee the truth of the conclusion.

Component propositions are repeated, or subjects
and predicates within propositions are repeated, in the argument to make information already contained in the premises explicit (note explicit info may not be obvious). There are many forms of deductive arguments, e.g., “modus ponens”:

How would you write this into an equation:

Answer 60

If P, then Q
P
Therefore, Q

Question 61

If an argument is valid, then the ______ must be true if the _____ are true

Answer 61

then the conclusion must be true if the premises are true; i.e., the truth of the premises guarantees the truth of the conclusion. Otherwise, the argument is invalid.