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He's a Platonist and I am a positivist. He's worried that Schrodinger's cat is in a quantum state, where it is half dead and half alive. He feels that can't correspond to reality. But that doesn't bother me. I don't demand that a theory correspond to reality because I do not know what it is. Reality is not a quality you can test with litmus paper. All I am concerned with is that the theory should predict the results of measurements. Quantum theory does this very successfully. It predicts that the result of an observation is either that the cat is alive or that it is dead. It is like you can't be slightly pregnant; you either are or you aren't.

Stephen Hawking#43

SciencePhysicsPhilosophyQuantumReality

About this quote

What does it mean?
Hawking prioritizes predictive power over philosophical certainty about reality in quantum mechanics.
In plain terms
He cares if theory predicts results, not if it matches what reality is.
What can you take from it?
Predictive success matters more than defining reality.

Where it applies

  • physics research
  • philosophy of science
  • debates

Putting it to work

  • focus on testable results
  • set aside metaphysical debates
  • trust data over intuition

Questions to consider

  • Does prediction prove reality?
  • Why do physicists disagree on reality?

Another view

Ignoring reality questions can limit deeper theoretical understanding.

More from Stephen Hawking

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  2. I find that American & Scandinavian accents work better with women.

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  3. You have to be creative to do science. Otherwise you're just repeating tired formulas

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