Ayer's Verificationism

Ayer's Verificationism

1. Verifyability in principle

   • "There is life on Mars"
     • Verifiable in PRINCIPLE, but we don't have the technology to find out in PRACTICE.

2. Practical verification

   • Can be tested in reality

3. Strong verification

   • Observation and experience...conclusively verified.

4. Weak Verification

   • Observation and experience...probable
   • "All human beings are mortal"
     • We would need to kill every human being who lives and will live.
       • This is impossible, but we accept it as fact.

5. Language is only meaningful if it can be verified by sense observation.

6. Ayer's Second Edition

   • The distinction between strong and weak is not a real distinction
   • Rejects putative (assuming) statements
   • Language is only meaningful if it is analytic or empirically verifiable.
   • Weak verification allows meaning to everything and is therefore too liberal.
   • Single experiences
     • An experience, while it may not be describable, is verified by it's occurrence.
   • Directly verifiable statements
     • A statement that is verifiable by observation
   • Indirectly verifiable statements
     • The statement cannot be verified by observation, but by supporting statements which can
   • Criticisms of Verificationism
     • Verificationism is not verifiable
     • God-talk is eschatologically verifiable
       • John Hick
       • Religion is verifiable in principle, so it meets the conditions of verification.
       • (Verifiable in principle but not falsifiable)
     • Strong verification excludes many areas of knowledge
       • (There is no sense observation available for historical facts)
       • Swinburne: It excludes universal statements like 'water boils at 100 degrees"
     • What counts as evidence, exactly?
       • Swinburne: There are many areas of debate where getting people to agree on what counts as evidence would be the issue.
     • Statements can be meaningful and unverifiable
       • Swinburne: Toys in a cupboard.
         • The toys only come out at night. Meaningful but unverifiable. 
       • Schrodinger's cat
         • A radioactive particle could kill the cat at any time. If you open the box you could trigger it. You can't verify if the cat is dead or alive