# Fuzzy logic

 Cogito ergo sumLogic and rhetoric Key articles General logic Bad logic v - t - e
 This page contains too many unsourced statements and needs to be improved. Fuzzy logic could use some help. Please research the article's assertions. Whatever is credible should be sourced, and what is not should be removed.

Fuzzy logic is a term of techno-jargon to describe a class of logics in which a finite set of discrete truth values (e.g., "true" and "false" in binary logics) is replaced with an uncountable continuum of truth values, generally the set of real numbers between 0 and 1.[1]

Fuzzy logic is related to probabilistic logic, in which truth values convey a probability that a sentence is true in the same sense as binary logic; e.g., if the truth value of proposition A is 0.5, it means that A has a 50-50 probability of being true, but still must be either wholly true or wholly false. In fuzzy logic, by contrast, a truth value of 0.5 means that a statement is only "half true;" for example, if a proposition "The glass is full" had a truth value of 0.5, it could be interpreted as "The glass is half full."

The fuzziness of fuzzy logic can occur in two ways, and will be dependent upon the input probabilities' accuracy and precision, and the problem of garbage in garbage out.

## Fuzzy math

 “”I was trying to do some fuzzy math. I used his calculator. —Dubya after a October 2000 presidential debate.[2]

"Fuzzy logic" is not to be confused with "fuzzy math", which was coined by then-presidential candidate George W. Bush during his first presidential debate with Democratic nominee Al Gore. Bush initially employed the phrase — along with a similar phrase, "phony numbers" — to criticize Gore's tax policy.[3] His use of the phrase is a classic example of the appeal to ridicule fallacy, as well as a prototype of his signature "Bushisms".