1928 | Elements of Mathematical Logic |
7.I | p.94 | 8942 | 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. |