Philosophy

Reasoning

To perform an inference

Statement

Sentence speaker uses to assert a truth claim

Argument

Inference expressed in language, composed of several statements

Premises

Sentences offered in support of another statement

Conclusion

What the premises are trying to support

Inference Indicators

Therefore, so, hence, thus, etc

Logical Strength

How well premises justify and support their intended conclusion (Independent from the truth or falsity of constituent statements)

Deductive Arguments

Truth of the premises guarantee the truth of the conclusion (If premises are true, conclusion must be true)

Non Deductive Arguments

Truth of premises provide evidence for truth of conclusion without guaranteeing the truth of the conclusion 

Sound Argument

Conclusion logically follows the premises, and all the premises are true

Cogent Argument

Premises offer probable support of the conclusion but does not guarantee the truth of it

Counterfactual arguments

An argument with premises describing state of affairs that we take to nonactual

Reductio Ad Absurdum

Makes an opponent’s argument seem absurd by taking your opponent’s argument to extreme lengths and finding contradictions

Reference Theory of Meaning

the meaning of a word is the entity or class of entities to which it refers or is about. (Fido refers to the dog, dog refers to the set of all dogs)

Idea Theory of Meaning

the meaning of a word is the idea or mental image with which a speaker associates the word

Use Theory of Meaning

the meaning of a word is given by the way that the word is used in a sentence

Descriptive

Describing or conveying information

Evaluative

To make a judgement about something

Emotive

To evoke emotion

Persuasive

To persuade an audience to do something

Interrogative 

To elicit information by asking a question

Directive

To command others to do something

Performative

To perform an action

Recreational

For fun or amusement

Exclusive

If one event happens, the other cannot occur at the same time

Exhaustive

Includes every possible element

Referent

whatever worldly entity or class of entities that the term is about or picks out (Referent of bachelor is the set of all bachelors)

Sense

The way the speaker thinks of the referent when using the term (Bachelor means unmarried male)

Reportive Definition

Definition that reports standard usage (e.g dictionary)

Stipulative Definition

Definition that stipulates usage (e.g sentence declaring how statement will be used)

Essentialist Definition

Definition that reveals the underlying nature of something (e.g Socrates when asking “what is justice?”)

Principal of Charity

Whenever two or more adaptations are possible, we should adopt the more reasonable one

Ambiguous sentence

Sentence with two or more different meanings

Vague sentence

Sentence with no clear precise meaning

Referential Ambiguity

Word or property that could refer to more than one thing

Distributive Use

Applies to each individual (each member on the team is large)

Collective Use

Applies to the group as a whole (the team has a large number of members)

Grammatical Ambiguity

When the ambiguity arises from the sentence structure itself

Use and mention (ambiguity)

Sometimes ambiguity arises because one fails to distinguish between using a word and mentioning a word. (Tom said I was angry vs Tom said “I was angry”)

Analytical Statement

True by Definition

Contradictory Statement

False by Definition

Synthetic Statement

Falsity or truth is not determined by definition

Sufficient Condition

B guarantees that A will occur (e.g being 18 is a sufficient condition to vote)

Necessary Condition

B cannot occur without A (e.g Air is a necessary condition for human life)

Jointly Sufficient Condition

A set of necessary conditions create a sufficient condition

Single Argument

A premise offered in support of a conclusion

T arguments

2 or more premises offered that work together in support of a conclusion

V arguments

2 or more premises offered that individually offer support of a conclusion 

Fallacies Approach

Checking if the argument has any fallacies

Fallacy

Error or weakness that takes away from an argument’s soundness while making it sound better than it really is

Criterial Approach

Checking if the argument is acceptable, relevant, and adequate

Acceptability

If common knowledge, or if evidence meets appropriate standard

Empirical Truth Claim

Verifiable through observation

Statistical Empirical Claim

Claim about a certain proportion of a group

Universal Empirical Claim

Claim about ALL members of a class

Begging the question

Premises presupposes truth of conclusion

Equivocation

Using the same term or phrase in different senses when the logical strength of one’s argument depends on the term or phrase being used in the same sense

Inconsistency

When one contradicts themselves in the process of making an argument

False Dichotomy

An argument rests on a false dichotomy when one of its premises inaccurately represents alternatives as being exclusive, exhaustive, or both.

Appeals to Authority

1. The authority must be identified.

2. The authority must be generally recognized by the experts in the field.

3. The particular matter in support of which an authority is cited must lie within his or her field of expertise.

4. The field must be one in which there is genuine knowledge.

5. There should be a consensus among the experts in the field

Appeal to anecdotal evidence

Drawing on a single story to assert truth (This happened to me once so it must be true)

Appeal to ignorance

Asserting truth because there is no evidence that disproves it

Slippery Slope Fallacy

When a chain of predictions is linked together without realizing that while the predictions might be strong individually, they are weak as an entire chain.

Post Hoc

Concluding that since one event happened before another, the first event must have caused the second (The stove was working until you moved in, therefore you made the stove break)

Confusing cause and effect

as moth populations grew during the industrial revolution, the smog and air quality got worse. Therefore the smog must have been caused by the moths

Common Cause

When we overlook the possibility of a common cause when trying to identify the causal relationship between correlated events (seeing a correlation between people who eat ice cream and people who drown and blaming ice cream for drownings rather than the hot weather)