---
title: Normal Form
TARGET DECK: Obsidian::STEM
FILE TAGS: logic
tags:
  - logic
---

## Overview

An object is said to be in **normal form** if it cannot be reduced any further. Examples of normal form include:

* [[equiv-trans#Normal Forms|Conjunctive Normal Form]]
* [[equiv-trans#Normal Forms|Disjunctive Normal Form]]
* [[quantification#Identifiers|Prenex Normal Form]]

%%ANKI
Basic
What does it mean for an object to be in normal form?
Back: It cannot be rewritten/reduced any further.
Reference: Gries, David. *The Science of Programming*. Texts and Monographs in Computer Science. New York: Springer-Verlag, 1981.
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END%%

%%ANKI
Basic
What zero-order logical normal form(s) have only $\land$ and $\lor$ operators?
Back: CNF and DNF
Reference: Gries, David. *The Science of Programming*. Texts and Monographs in Computer Science. New York: Springer-Verlag, 1981.
<!--ID: 1707675369145-->
END%%

%%ANKI
Basic
What first-order logical normal form(s) writes bound identifiers before free ones?
Back: PNF
Reference: Gries, David. *The Science of Programming*. Texts and Monographs in Computer Science. New York: Springer-Verlag, 1981.
<!--ID: 1707675369187-->
END%%

## References

* Gries, David. *The Science of Programming*. Texts and Monographs in Computer Science. New York: Springer-Verlag, 1981.