Philosophy:Normal form (natural deduction)
From HandWiki
An inference of natural deduction is a normal form, according to Dag Prawitz, if no formula occurrence is both the principal premise of an elimination rule and the conclusion of an introduction rule.[1]
References
- ↑ Prawitz, Dag (2006-02-24) (in en). Natural Deduction: A Proof-Theoretical Study. Courier Dover Publications. ISBN 978-0-486-44655-4. https://books.google.com/books?id=sJj3DQAAQBAJ&q=%22Normal+form%22.
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