Namespaces
Variants
Actions

Difference between revisions of "Propositional formula"

From Encyclopedia of Mathematics
Jump to: navigation, search
(TeX)
m
 
(2 intermediate revisions by one other user not shown)
Line 1: Line 1:
 +
{{MSC|03}}
 
{{TEX|done}}
 
{{TEX|done}}
An expression constructed from propositional variables (cf. [[Propositional variable|Propositional variable]]) by means of the propositional connectives (cf. [[Propositional connective|Propositional connective]]) $\&,\lor,\supset,\neg,\equiv$ (and possibly others) in accordance with the following rules: 1) each propositional variable is a propositional formula; and 2) if $A,B$ are propositional formulas, then so are $(A\&B)$, $(A\lor B)$, $(A\supset B)$, and $(\neg A)$.
+
 
 +
A ''propositional formula'' is
 +
an expression constructed from propositional variables (cf. [[Propositional variable|Propositional variable]]) by means of the propositional connectives (cf. [[Propositional connective|Propositional connective]]) $\&,\lor,\supset,\neg,\equiv$ (and possibly others) in accordance with the following rules: 1) each propositional variable is a propositional formula; and 2) if $A,B$ are propositional formulas, then so are $(A\mathbin\&B)$, $(A\lor B)$, $(A\supset B)$, and $(\neg A)$.
  
 
If $\sigma$ is a set of propositional connectives (a fragment), then a propositional formula in the fragment $\sigma$ is a propositional formula in whose construction rule 2) only connectives from $\sigma$ are used.
 
If $\sigma$ is a set of propositional connectives (a fragment), then a propositional formula in the fragment $\sigma$ is a propositional formula in whose construction rule 2) only connectives from $\sigma$ are used.
  
 +
====References====
 +
{|
 +
|-
 +
|valign="top"|{{Ref|Wó}}||valign="top"|  R. Wójcicki,  "Theory of logical calculi", Kluwer  (1988)  pp. 13; 61    {{MR|1009788}}  {{ZBL|0682.03001}}
  
 
+
|-
====Comments====
+
|valign="top"|{{Ref|Zi}}||valign="top"| Z. Ziembinski,  "Practical logic", Reidel  (1976)  pp. Chapt. V, §5  {{ZBL|0372.02001}}
 
+
 
 
+
|-
====References====
+
|}
<table><TR><TD valign="top">[a1]</TD> <TD valign="top"> Z. Ziembinski,  "Practical logic" , Reidel  (1976)  pp. Chapt. V, §5</TD></TR><TR><TD valign="top">[a2]</TD> <TD valign="top">  R. Wójcicki,   "Theory of logical calculi" , Kluwer  (1988)  pp. 13; 61</TD></TR></table>
 

Latest revision as of 13:57, 30 December 2018

2020 Mathematics Subject Classification: Primary: 03-XX [MSN][ZBL]

A propositional formula is an expression constructed from propositional variables (cf. Propositional variable) by means of the propositional connectives (cf. Propositional connective) $\&,\lor,\supset,\neg,\equiv$ (and possibly others) in accordance with the following rules: 1) each propositional variable is a propositional formula; and 2) if $A,B$ are propositional formulas, then so are $(A\mathbin\&B)$, $(A\lor B)$, $(A\supset B)$, and $(\neg A)$.

If $\sigma$ is a set of propositional connectives (a fragment), then a propositional formula in the fragment $\sigma$ is a propositional formula in whose construction rule 2) only connectives from $\sigma$ are used.

References

[Wó] R. Wójcicki, "Theory of logical calculi", Kluwer (1988) pp. 13; 61 MR1009788 Zbl 0682.03001
[Zi] Z. Ziembinski, "Practical logic", Reidel (1976) pp. Chapt. V, §5 Zbl 0372.02001
How to Cite This Entry:
Propositional formula. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Propositional_formula&oldid=31453
This article was adapted from an original article by S.K. Sobolev (originator), which appeared in Encyclopedia of Mathematics - ISBN 1402006098. See original article