According to Ayer, where does all genuine knowledge come from?
Science (common sense)
What are arguments? What are propositions?
A proposition is the meaning of a sentence. An argument is a collection of propositions; a
conclusion supported by premises
What two things have to be true of a good (i.e. sound) argument?
It must be valid and have true premises
What two things does Ayer not argue? Why?
That all premises must come from sense experience or that false premises don't need to be
shown. He doesn't argue these bc he uses the def of rationalism - transcendental premises
can be established by intellectual intuition
What are two kinds of meaningless sentences?
Violations of logic and grammatically correct nonsense
What is the criterion of verifiability? What kinds of claims/sentences fail the criterion? What
does that mean for them?
It states that a sentence is factually significant to a person, if and only if, he knows how to
verify the proposition which it intends to express
What sentences are meaningful despite failing the criterion of verifiability? Why?
Tautologies are meaningful bc the definition and the sentence are the same thing
What is the distinction between practical verifiability and verifiability in principle? Why is this
distinction useful for Ayer?
Something practically verifiable has already been verified or is able to be verified now. If it's
verifiable in principle it isn't able to be verified yet but it is plausible
Science (common sense)
What are arguments? What are propositions?
A proposition is the meaning of a sentence. An argument is a collection of propositions; a
conclusion supported by premises
What two things have to be true of a good (i.e. sound) argument?
It must be valid and have true premises
What two things does Ayer not argue? Why?
That all premises must come from sense experience or that false premises don't need to be
shown. He doesn't argue these bc he uses the def of rationalism - transcendental premises
can be established by intellectual intuition
What are two kinds of meaningless sentences?
Violations of logic and grammatically correct nonsense
What is the criterion of verifiability? What kinds of claims/sentences fail the criterion? What
does that mean for them?
It states that a sentence is factually significant to a person, if and only if, he knows how to
verify the proposition which it intends to express
What sentences are meaningful despite failing the criterion of verifiability? Why?
Tautologies are meaningful bc the definition and the sentence are the same thing
What is the distinction between practical verifiability and verifiability in principle? Why is this
distinction useful for Ayer?
Something practically verifiable has already been verified or is able to be verified now. If it's
verifiable in principle it isn't able to be verified yet but it is plausible
