logical Positivism and verification

define logical analysis

The method of clarification of philosophical problems

what is LP?

a philosophical movement that established the verification principle

what is tautology?

A self explanatory statement e.g. All bachelors are single males

what is the verification principle?

A proposition can be considered meaningful only if there is a method by which it can be tested for truth

where did LP originate from?

It grew out of a group known as the Vienna Circle, who met during the 1920s and 1930s. They considered their task to be the philosophical lye driven systematic reduction of all knowledge to basic scientific and logical formulations

What did the LP Acknowledge?

• Anything outside of basic logical and scientific tenets is dismissed as meaningless due to the fact it is unverifiable

• Tautological statements and statements that could be verified by observations from first-person sense experience

what are statements that are outside of logical reasoning and EE?

considered to be meaningless

what is a quote from Moritz Schlick?

‘The meaning of a proposition is the method of verification’

what are synthetic statements?

A statement that could be verified by some form of sense experience or experiment

what are analytic statements?

Where the truth of the statement is determined within the statement itself

where did Ayer promote LP?

‘Language, Truth and Logic’ (1936)

what did Ayer remain loyal to?

Empiricism, convinced that all knowledge of the world derived from sense experience and that nothing in experience justifies a belief in God or in any other metaphysical entity

what are Ayer’s modifications on the verification principle?

• Verification in practice - practically impossible to check truth of falsity of statement

• Verification in principle - we know in theory what is required to check, but is impractical

what are the other two modifications?

• Strong verification - a statement is conclusively verified empirically

• Weak verification - some empirical evidence counts towards a statement, making it probable

what did Ayer admit in 1978?

His earlier work was ‘mostly false’

how can verification in practice be tested?

Temperature of a room is 18 Celsius - thermometer

how can verification in principle be tested?

Temperature of Earth's core is 6000 degrees Celsius - we know how to test this claim but can't practically do it

example of strong verification?

Bill committed murder - can be strongly verified by ‘We all saw Bill commit murder’

example of weak?

Can be weekly verified by ‘even if we didn't see it Bill doesn't have an alibi and it was his weapon’

what does the VP show?

Religious and metaphysical statements plus this all statements are meaningless as they are neither analytic or synthetic

Even with Ayer’s modifications what is it impossible to do?

Verify God's goodness in principle or to use weak verification to find evidence to count towards the assertions because we do not know anything that could support it

What is a quote from Ayer?

‘A sentence is factually significant if, and only if, we know how to verify the proposition it purports to express - that is, if we know what observations would lead us to accept the proposition as true o reject it as false’