Logic Quiz 1

Argument

A set of statements in which premises are offered as support for a conclusion

Premise

A statement offered as a reason or piece of evidence for the conclusion

Conclusion

the statement an argument is trying to prove; what the premises supports

Deductive

An argument meant to give conclusive (all or nothing) support to its conclusion

Inductive

An argument meant to give probable, but not certain, support to its conclusion

Analogical

An argument that concludes something about one case based on its similarity to another case

Valid

A deductive argument where, if all premises are true, the conclusion must be true

Invalid

A deductive argument where the conclusion doesn’t necessarily follow, even if the premises are true

Sound

A deductive argument that is valid and has all true premises

Unsound

A deductive argument that is invalid or has at least one false premise

Cogent

A strong inductive argument with all true premises

Tacit (premise)

a unstated premise that’s implied and needed for the argument to make sense

Deductive vs. Inductive

Deductive claims certainty; inductive claims probability

Validity vs. Soundness

Validity = correct logical form

soundness = valid form + true premises

Valid but unsound?

Yes, correct form, but false premise

Invalid but sound?

Not possible