Section 1: Evaluating Arguments and Evidence

Question 1

propositions

Answer 1

Statements that are true or false.

Question 2

non-propositions

Answer 2

Sentences that are not statements about matters of fact (or fiction). They do not make a claim that can be true or false.

Question 3

simple propositions

Answer 3

have no internal logical structure, meaning whether they are true or false does not depend on whether a part of them is true or false. They are simply true or false on their own.

Question 4

complex propositions

Answer 4

have internal logical structure, meaning they are composed of simple propositions. Whether complex propositions are true or false depends on whether their parts are true or false and how those parts are connected.

Question 5

deductive arguments

Answer 5

meant to provide decisive support for their conclusions

ex: mathematical proofs

Question 6

inductive arguments

Answer 6

meant to provide probable support for their conclusions

ex: analogy, call to authority

Question 7

abduction (also called inference to the best explanation)

Answer 7

arguments where the best available explanation is chosen as the correct explanation

Question 8

conclusion indicators

Answer 8

therefore, so, it follows that, hence, thus, entails that, we may conclude that, implies that, wherefore, as a result

Question 9

premise indicators

Answer 9

because, for, given that, in that, since, as indicated by

Question 10

conclusion

Answer 10

is the claim that the whole argument is intended to support or demonstrate or prove

it is the reason we make an argument: to support or demonstrate the conclusion

Question 11

premise

Answer 11

are the claims, evidence, and ideas intended to support the conclusion

they are the assumptions we’re asked to make

Question 12

argument defined

Answer 12

a set of statements, some of which (the premises) attempt to provide a reason for thinking that some other statement (the conclusion) is true

Question 13

truth

Answer 13

A true proposition accurately represents reality.

Question 14

validity

Answer 14

It is impossible for the premises to be true while the conclusion is sound.

In a good deductive argument structure, true premises would make the conclusion necessarily true. (If not, it is an invalid structure.)

Question 15

soundness

Answer 15

A valid argument with true premises.

A deductive argument is sound if it has a valid structure and all its premises are true. (If an argument is deductive but has either an invalid structure or at least one false premise, then it is an unsound argument.)

Question 16

cogent argument

Answer 16

All True Premises + Strong Inductive Support

Question 17

formal fallacy

Answer 17

affirming the consequent, or an argument with bad structure

Question 18

informal fallacy

Answer 18

the structure of your argument is not the issue; instead, someone takes exception to the content of your argument

Question 19

affirming the consequent (invalid)

Answer 19

If I am in New York, then I am in the USA.
I am in the USA.
Therefore, I am in New York

If X, then Y.
Y.
Therefore, X.

Question 20

antecedent

Answer 20

the simple proposition that immediately follows the word “if”

Question 21

consequent

Answer 21

the simple proposition that immediately follows the word “then”

Question 22

denying the antecedent (invalid)

Answer 22

If I am in New York, then I am in the USA.
I am not in New York.
Therefore, I am not in the USA.

possible for the conclusion to be false even if the premises are true.

If X, then Y not X.
Therefore, not Y.

the second premise says that the antecedent of the first premise is not the case; the second premise denies the antecedent

Question 23

modus ponens (affirming the antecedent) (valid)

Answer 23

if X, then Y
X
therefore Y