Work · Analytic Philosophy
Protocol Sentences
There is no bedrock of certain experience: even records of observation can be discarded – the essay with the ship that must be rebuilt at sea.
Introduction
Neurath’s essay appeared in the journal Erkenntnis in 1932/33 and set off the protocol-sentence debate in the Vienna Circle. Against the search for a basis of certain experience, he argues that protocol sentences are ordinary physicalist statements that include the observer’s name and the time, for instance “Otto’s protocol at 3:17 …”. Like any other statement, they can be rejected when they conflict with the system of science. The essay contains the image of sailors who rebuild their ship at sea without ever being able to start afresh in dry dock. Carnap replied with a more liberal view of protocol sentences, Schlick defended indubitable “affirmations”, and Popper criticised Neurath in The Logic of Scientific Discovery.
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