Below the truth table for implication (with arguments reversed) they claim > It ... | Hacker News

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		tromp on Oct 7, 2023 \| parent \| context \| favorite \| on: Subtraction is functionally complete Below the truth table for implication (with arguments reversed) they claim > It turns out this truth table is functionally complete [1] yet the linked Wikipedia article clearly states that > every two-element set of connectives containing NOT and one of { AND, OR, IMPLY } is a minimal functionally complete subset of { NOT, AND, OR, IMPLY, IFF }. I.e. IMPLY by itself is not functionally complete. [1] https://en.wikipedia.org/wiki/Functional_completeness

Epa095 on Oct 7, 2023 | [–]

The article kind of took for granted that you could include the number 0 as well, and with "-0" he got bottom, so its the 2-element set {-->, _|_}.

gliptic on Oct 7, 2023 | [–]

The unstated assumption is that you also have FALSE.

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