Philosophy Test 1: Arguments FROM QUIZLET

Why do philsophers use reason?

They believe it can help them solve problems, analyze concepts, and live the good life

What is an argument (Weston's Definition)

To give an argument means to offer a set of reasons or evidence in support of a conclusion.

Weston's Definition

To give an arguemnt means to offer a set of reasons or evidence in support of conclusion

-arugments are used to elucidate and explicate claims

-arguments are used to asses whether a claim is true or false (strong or weak)

-arguments are used to explain and defend claims

Arguments have two components:

1. Premises (reasons or evidence)

2. Conclusion (claim)

Premises

reasons or evidence

Conclusion

claim

Premise Indicators:

since

because

given then

for

Conclusion Indicators

therefore

so

as a result

it follows that

implies that

Two Types of Arguments:

Deductive and Inductive

Inductive

an argument in which the premises are claimed to support the conclusion in such a way that it is improbable that the premises be true and the conclusion false. THus, the conclusion is claimed to follow probably from the premises. (Strong or Weak)

Inductive Example

Socrates was Greek.

Most Greeks eat fish.

So, Socrates ate fish.

Inductive indicators

probably

likely

plausibly

Three Types of Inductive Arguments

1. Argument by analogy

2. Argument by authority (source)

3. Argument by cause

Inductive: Argument by analogy

Argument that depends upon the existence of an analogy, or similarity, between two things or state of affairs.

A is similar to B in relevant ways

B has property P

A has property P

Inductive: Argument from authority

Argument in which the conclusion rests on a statement made by some presumed authority or witness

R is a reliable authority regarding S

R sincerely assersts S

So, S

Inductive: Argument from cause

A causal claim is one that asserts that there is a relationship between two events such that one is the effect of the others.

X causes Y

Deductive

an argument in which the premises are claimed to support the conclusion in such a way that it is impossible that the preises be true and the conclusion false. Thus, the conclusion is claimed to follow necessarily from the premises. (Valid or Invalid)

Deductive Example

All men are mortal

Socrates is a man

So, Socrates is mortal

Deductive indicators

Necessarily

certainly

absolutley

Valid Argument

Argument such that it is impossible for the premises to be true and the conclusion false

Invalid Argument

Argument such that it is possible for the premises to be true and the conclusion false.

Deductive: Modus Ponens (MP)

Affirming the Antecedent

If P then Q

P

Therefore, Q

Deductive: Modus Tollens (MT)

Denying the Consequent

If P, then Q

not Q

Therefore, Not P

Deductive: Hypothetical Syllogism (HS)

If P then Q

If Q then R

Thus, If P then R

Deductive: Disjunctive Syllogism (DS)

P or Q

Not P

Thus, Q

Deductive: Dilemma (D)

P or Q

If P then R

If Q then S

Thus, R or S

Deductive: Affirming the Consequent

If P then Q

Q

Thus, P

Deductive: Denying the Antecedent

If P then Q

not P

Thus, not Q