Flashcards in Intro to Logic Deck (58)
What is Logic?
The analysis and appraisal of arguments
What is Philosophy?
Reasoning about the ultimate questions of life
What is an Argument?
a set of statements consisting of premises and a conclusion
What is a Premise?
What is a Conclusion?
a statement made based on supporting evidence
What is true/false?
statements can either be true, correct, or false, incorrect
What is the Law of Non-Contradiction?
contradictory propositions cannot both be true in the same sense at the same time, e. g. the two propositions "A is B" and "A is not B"
What is the Law of Excluded Middle?
the law of excluded middle states that for any proposition, either that proposition is true or its negation is true
What is valid/invalid?
Valid is if the premises support the conclusion, invalid if the premises do not
What is the difference between true and valid?
true is connected to statements, valid is connected to agruments
What is "sound"?
A "sound" argument is both valid (conclusion follows the premises) and all the premises are true
What is ".˙."?
What is "wff"?
A well formed formula is a finite sequence of symbols from a given alphabet that is part of a formal language
What is a deductive argument?
A deductive argument has a tight connection between premises and conclusion, it would be impossible for the premises to all be true but have a false conclusion
What is an inductive argument?
An inductive argument has a loose connection between premises and conclusion, the conclusion relative to the premises is only a good guess (could be true or false)
What is a definition?
a rule of paraphrase intended to explain the meaning of a word or phrase
What is an interchange test?
A definition test where if A=B is true, then B=A must be true
What is a lexical definition?
a definition explaining current usage of a word or phrase
What is a stipulative definition?
a definition specifying your own usage of a word or phrase
What is a clarifying definition?
a definition that stipulates a clearer meaning for a vague term
What is a recursive definition?
a definition that first specifies some things that the term applies to and then specifies if the term applies to certain things
What is a logical positivism?
using the verifiability criterion of meaning
Who is A.J. Ayer?
a logical positivist who appealed to the verifiability criterion of meaning
What is an analytic sentence?
a statement that is self-contradictory to deny
What is a synthetic sentence?
any statement which cannot be determined true or false by linguistic meaning alone
What is verifiability criterion of meaning?
(LP) If there is no way to test a statement, then it has no meaning– nothing in it could be true or false
Who is William James?
Logistician who suggests to determine the "cash-value" of a statement
What is pragmatism?
if the truth of a statement has no practical meaning to anyone, then it has no meaning at all
What is a logically necessary truth?
the same idea as analytic statements, a truth that is self-contradictory to deny