Difference between revisions of "First-order language"

From Conservapedia
Jump to: navigation, search
(undeadend)
(added more links, bit more explanation.)
Line 1: Line 1:
A '''First-order language''' consists of the following symbols:
+
A '''First-order language''' in [[Zermelo-Fraenkel]] set theory consists of the following symbols:
#A set of constants, such as ''A'', ''B'', ''C'', ...
+
#A set of [[constant]]s, such as ''A'', ''B'', ''C'', ...
#A set of n-ary relations such as ''>(x, y)''.
+
#A set of n-ary [[relation]]s such as ''>(x, y)''.
#A set of n-ary functions such as ''+(x, y)''.
+
#A set of n-ary [[function]]s such as ''+(x, y)''.
 
#An [[infinite]] set of variables such as ''x'', ''y'', ''z'',...
 
#An [[infinite]] set of variables such as ''x'', ''y'', ''z'',...
 
#The connectives <math>\neg</math>, <math>\wedge</math>.
 
#The connectives <math>\neg</math>, <math>\wedge</math>.
#quantifiers: <math>\forall</math>, <math>\exists</math>.
+
#[[quantifier]]s: <math>\forall</math>, <math>\exists</math>.
 
#parenthesis: <math>(</math>, <math>)</math>.
 
#parenthesis: <math>(</math>, <math>)</math>.
#The equality symbol <math>=</math>.  
+
#The [[equality]] symbol <math>=</math>.
 +
 
 +
First-order languages are used to describe [[mathematics]] in [[mathematical notation]] with [[mathematical formula]]e.
  
 
[[category:languages]]
 
[[category:languages]]
 +
[[category:logic]]
 
[[category:mathematics]]
 
[[category:mathematics]]

Revision as of 00:22, March 9, 2008

A First-order language in Zermelo-Fraenkel set theory consists of the following symbols:

  1. A set of constants, such as A, B, C, ...
  2. A set of n-ary relations such as >(x, y).
  3. A set of n-ary functions such as +(x, y).
  4. An infinite set of variables such as x, y, z,...
  5. The connectives , .
  6. quantifiers: , .
  7. parenthesis: , .
  8. The equality symbol .

First-order languages are used to describe mathematics in mathematical notation with mathematical formulae.