Peter Norvig on Fuzzy Sets - Dictionary of Arguments
Norvig I 550
Fuzzy sets/vagueness/Norvig/Russell: Fuzzy set theory is a means of specifying how well an object satisfies a vague description. For example, consider the proposition “Nate is tall.” Is this true if Nate is 5’ 10’’? Most people would hesitate to answer “true” or “false,” preferring to say, “sort of.” Note that this is not a question of uncertainty about the external world - we are sure of Nate’s height.
The issue is that the linguistic term “tall” does not refer to a sharp demarcation of objects into two classes - there are degrees of tallness. For this reason, fuzzy set theory is not a method for uncertain reasoning at all. Rather, fuzzy set theory treats Tall as a fuzzy predicate and says that the truth value of Tall (Nate) is a number between 0 and 1, rather than being just true or false.
The name “fuzzy set” derives from the interpretation of the predicate as implicitly defining a set of its members - a set that does not have sharp boundaries. >Vagueness/Philosophical theories, >Sorites/Philosophical theories._____________Explanation of symbols: Roman numerals indicate the source, arabic numerals indicate the page number. The corresponding books are indicated on the right hand side. ((s)…): Comment by the sender of the contribution. Translations: Dictionary of Arguments The note [Author1]Vs[Author2] or [Author]Vs[term] is an addition from the Dictionary of Arguments. If a German edition is specified, the page numbers refer to this edition.
Stuart J. Russell
Artificial Intelligence: A Modern Approach Upper Saddle River, NJ 2010