In the game of Vish (short for vicious circle), players compete to find circularity in dictionary definitions. Irish mathematician and physicist, John Lighton Synge, invented the multi-player, refereed game to emphasize the circular reasoning implicit in the defining process of any standard dictionary.
In his book, "Projective Geometry", H.S.M. Coxeter cites "Vish" in his discussion of definitions in mathematics:
 ;templatestyles src="Template:Blockquote/styles.css" / ;Vish illustrates the important principle that any definition of a word must inevitably involve other words, which require further definitions. The only way to avoid a vicious circle is to regard certain "primitive concepts" as being so simple and obvious that we agree to leave them undefined.
Notes.
 ;templatestyles src="Reflist/styles.css" / ;