Difference between revisions of "Universe of discourse"

From Lojban
Jump to: navigation, search
(As coined by Boole)
 
Line 5: Line 5:
 
== As coined by Boole ==
 
== As coined by Boole ==
 
<blockquote>In every discourse … there is an assumed or expressed limit within which the subjects of its operation are confined. The most unfettered discourse is that in which the words we use are understood in the widest possible application, and for them the limits of discourse are co-extensive with those of the universe itself. But more usually we confine ourselves to a less spacious field. … Now, whatever may be the extent of the field within which all the objects of our discourse are found, that field may properly be termed the '''universe of discourse'''. Furthermore, this universe of discourse is in the strictest sense the ultimate subject of the discourse.</blockquote>
 
<blockquote>In every discourse … there is an assumed or expressed limit within which the subjects of its operation are confined. The most unfettered discourse is that in which the words we use are understood in the widest possible application, and for them the limits of discourse are co-extensive with those of the universe itself. But more usually we confine ourselves to a less spacious field. … Now, whatever may be the extent of the field within which all the objects of our discourse are found, that field may properly be termed the '''universe of discourse'''. Furthermore, this universe of discourse is in the strictest sense the ultimate subject of the discourse.</blockquote>
George Boole, ''The Laws of Thought'' (1854)
+
''The Laws of Thought'' (1854)

Latest revision as of 22:01, 11 May 2018

The universe of discourse or domain of discourse describes the plurality of entities over which variables may range.

Although the term "universe of discourse" was coined by George Boole in 1854, as early as 1846, Augustus De Morgan had referred to a similar concept, described as "the universe under consideration".

As coined by Boole

In every discourse … there is an assumed or expressed limit within which the subjects of its operation are confined. The most unfettered discourse is that in which the words we use are understood in the widest possible application, and for them the limits of discourse are co-extensive with those of the universe itself. But more usually we confine ourselves to a less spacious field. … Now, whatever may be the extent of the field within which all the objects of our discourse are found, that field may properly be termed the universe of discourse. Furthermore, this universe of discourse is in the strictest sense the ultimate subject of the discourse.

The Laws of Thought (1854)