Exercise · ZW-GODELS-INCOMPLETENESS-002 · ★☆☆ Basic

A result of Gödel is that certain systems contain propositions...

Choose one option.

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  • C. Neither provable nor refutable within the system

Explanation

Gödel showed that certain systems contain propositions that can be neither proved nor refuted within them. That is the central idea of the first incompleteness theorem.

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Review the concept: Gödel’s incompleteness

A consistent system \(\mathcal{S}\) that represents enough arithmetic is incomplete: there is a formula \(\varphi\) that it can neither prove nor refute.

\[\\exists\\varphi\\,(\\mathcal{S}\\nvdash\\varphi\\land\\mathcal{S}\\nvdash\\neg\\varphi)\]

More practice problems: gödel’s incompleteness

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