Logic Exam

logic

The branch of philosophy that studies the principles of good reasoning.

a premise is either true or false..

but not both

premise indicator words

Since, as, for, because, given that, assuming that, supposing that, in that, owing to, inasmuch as, also, in addition

conclusion indicator words

therefore, thus, so, in conclusion, it follows that, hence, we may infer that, implies/entails that, as a result, consequently, for that reason

explicating the argument

clearly identify the premises and the conclusion of the argument, by writing down the sentences that express them.

paraphrasing

turning all sentences in an argument into declarative sentences and eliminating any non-essential claims

enthymeme

argument that contains an unstated premise(s) or conclusion

the principle of charity

nterpreting a speaker's argument in the most rational way possible.

form

the logical relationship between the premise and the conclusion

content

the truth or falsity of the premise(s) and conclusion

deductive argument

aims to make the conclusion certain

valid argument

IF it premise(s) are true then its conclusion must be true

sound argument

its valid AND it premise(s) are true

unsound argument

its invalid AND/OR at least one of its premises are false

counterexample

new argument with the same form as the original with true premise(s) and false conclusion

induction indicators

probably, it is likely that, odds are that, it is a good bet that, chances are that, perhaps

inductive argument

aims to make the conclusion likely or probable

strong

more than 50%

weak

50% or less

cogent

strong AND its premises are true

not cogent

its weak AND/OR at least one premise is false

modus ponens

if A then B, A→B

modus tollens

if A then B, not B→not A

affirming the consequent

if A then B, B→A

denying the antecedent

if A then B, not A →not B

Disjunctive syllogism

A or B, Not A→B

affirming a disjunct

A or B, A→not B

Appeal to force

threatens the audience

argument from inappropriate authority

cites a source who lacks expertise

straw man

argument that inaccurately describes an opponents position, and proceeds to refute that position

argumentum ad hominem

attacks the person making the argument or finds guilt by association

red herring

an argument that diverts attention from the matter of the issue to a new topic

argument from ignorance

argument that concludes something must be the case because we lack evidence that it is not the case

post hoc

An argument that concludes one thing caused another merely on the grounds that it occurred before the other.

slippery slope

An argument that one event will inevitably lead to a catastrophically negative outcome, following a progression which is portrayed as a sequence of inevitable, rather than merely possible, consequences.

hasty generalization

An argument that makes a general claim about a population upon the basis of a sample that is inappropriately small.

biased sample

An argument that makes a general claim about a population upon the basis of a sample that is not representative of that population.

begging the question

uses the confusion in the premises to prove the conclusion

In-group bias

The tendency to make positive judgments towards those that one perceives as belonging to one's own group, or negative judgments towards those that one perceives as not belonging to one's own group.

availability

The tendency to make judgments upon the basis of evidence that is recent, familiar, or easily accessible.

Confirmation bias

The tendency to notice, agree with, and act upon information that supports one's pre-existing views and preferences.

Fundamental Attribution Error

The tendency to overestimate the importance of situational factors in explaining one's own negative behavior, and to underestimate their importance in explaining other's negative behavior.

sunk cost bias

The tendency to continue to funnel additional resources into a project in which one is already invested rather than making an assessment based on current circumstances.

Anchoring Bias

The tendency to base judgments and estimations upon the first piece of information to which one is exposed.

framing effect

The tendency to evaluate information differently depending upon the context in which it is presented, and the ways it is compared and contrasted with other pieces of information.

intermediate premise

provides support for the conclusion while is simultaneously supported by another background premises).

joint premise

only counts towards the conclusion when combined with another

tacit premise

unstated or implied premise