Key Terms

Support

If the premises are true how likely is the conclusion to be true?

Deductively valid

If the premises are true the conclusion cannot be false

Formal support

Support because of the form/structure of the argument

Non formal support

Strong support regardless of the structure

A priori truth

Truths that do not need investigation

A posteriori truth

Truths that need investigation

Sound

Deductively valid and true premises

Cogent

Acceptable premises and strong support

Necessary truth

True and could never be false

Conjunction

Combines two or more statements to make a third which says each of the simple ones are true

Disjunction

Combines two or more statements into a compound statement which says that either one or the other of the simple ones is true

Premise indicators

Because, since, as

Conclusion indicators

So, therefore, thus

Conditional sentence

If X then Y

Contingent truth

A statement which is true but could have been false

Necessary falsehood

A statement that is false and couldn't have been true

Contingent falsehood

A statement that is false but could have been true

Convergent

Conclusion is derived from each premise independently from the other

Linked

Conclusion is derived only by taking the two statements together

Disjunctive syllogism

Either P or Q. Not P. So, Q

Lexical definition

A formal and concise statement of the meaning of a word or phrase

Ostensive definition

Explaining the meaning of a word by pointing to an object that the word applies to

Reportive definition

Definitions that intend to describe how a word is actually used

Stipulative definition

A proposal of a new or special use of a word in a specific context

Essential definition

Definition in terms of features that are essential to a kind

Criterial definition

Definition by the way something appears or behaves or is used

Operational definition

Define a term with reference to a specific set of operations or procedures that determine whether the term applies

Fallacies of clarity (5)

Equivocation, vagueness, emotionally loaded language, guilt by association, euphemism

Fallacies of relevance (6)

False dichotomy, straw man, genetic fallacy, ad hominem, tu quoque, appeal to ignorance

Equivocation

A key word is used in two or more meanings and the premises only support the conclusion because the meanings are not distinguished from each other

Vaugueness

It is not clear where the boundaries of the term apply

Euphemism

Bland language to conceal things that are appalling

False dichotomy

When it is asserted that a pair of options is exhaustive when they are really not

Ad Hominem

attacking a person instead of arguing against the claims the person has put forwards

Tu Quoque

When its asserted than an arguer has a fault similar to the one they are criticising therefore the criticism can be dismissed

Appeal to ignorance

Arguing that a claim is true on the grounds that we do not. know that the claim is false

Genetic fallacy

When claims about how a given belief originated are asserted as reasons for or against that belief

Analogue subject

The thing you are comparing the primary subject to

Primary subject

The thing you are making the conclusion about

Consistency analogy

Features F, G, H justify a decision or action

Refutation by logical analogy

A consistency analogy but about arguments

Inductive analogy

Conclusions about what's likely to occur in the world

Fallacies around analogical reasoning (4)

Faulty analogy, two wrongs make a right, slippery assimilation, slippery precedent

Faulty analogy

When the similarities are too loose

Two wrongs make a right

Because two wrong things are similar and one is tolerated the other should be tolerated as well

Slippery assimilation

When we assume because cases can be arranged in a series the cases should all be assimilated

Slippery precedent

When we claim that an action we deem to be good should not be permitted because it will set a precedent for allowing similar acts that are bad

Modal words

Must, can't, have to

Inductive argument

An argument that moves from premises about things that have been observed in the past to a conclusion about something that has not yet been observed

Singlular induction

Inference going from big to small

Inductive generalisation

Inference going from small to big

Explanatory inductions

Arguing from observed data to a conclusion that asserts the probable cause of the data

Whats the difference between inductive analogies and singular inductions?

Inductive analogies make reference to features, singular inductions do not

How is perfect representation achieved?

When the sample is selected randomly

What does the sample being random mean?

Every member of the target population has an equal chance of being included in the sample

Stratified sampling

The sample is selected in a way that the significant characteristics within the population are proportionally represented within it