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Ideas of Jan Lukasiewicz, by Text

[Polish, 1878 - 1956, Professor at Warsaw University. In Dublin after 1945.]

1928 Elements of Mathematical Logic
7.I p.94 Lukasiewicz's L3 logic has three truth-values, T, F and I (for 'indeterminate')
     Full Idea: In response to Aristotle's sea-battle problem, Lukasiewicz proposed a three-valued logic that has come to be known as L3. In addition to the values true and false (T and F), there is a third truth-value, I, meaning 'indeterminate' or 'possible'.
     From: report of Jan Lukasiewicz (Elements of Mathematical Logic [1928], 7.I) by Jennifer Fisher - On the Philosophy of Logic
     A reaction: [He originated the idea in 1917] In what sense is the third value a 'truth' value? Is 'I don't care' a truth-value? Or 'none of the above'? His idea means that formalization doesn't collapse when things get obscure. You park a few propositions under I.