Degrees of Truth
Fuzzy logic and probabilistic logic are mathematically similar – both have truth values ranging between 0 and 1 – but conceptually distinct, owing to different interpretations—see interpretations of probability theory. Fuzzy logic corresponds to "degrees of truth", while probabilistic logic corresponds to "probability, likelihood"; as these differ, fuzzy logic and probabilistic logic yield different models of the same real-world situations.
Both degrees of truth and probabilities range between 0 and 1 and hence may seem similar at first. For example, let a 100 ml glass contain 30 ml of water. Then we may consider two concepts: Empty and Full. The meaning of each of them can be represented by a certain fuzzy set. Then one might define the glass as being 0.7 empty and 0.3 full. Note that the concept of emptiness would be subjective and thus would depend on the observer or designer. Another designer might equally well design a set membership function where the glass would be considered full for all values down to 50 ml. It is essential to realize that fuzzy logic uses truth degrees as a mathematical model of the vagueness phenomenon while probability is a mathematical model of ignorance.
Read more about this topic: Fuzzy Logic
Famous quotes containing the words degrees of, degrees and/or truth:
“When a thought of Plato becomes a thought to me,—when a truth that fired the soul of Pindar fires mine, time is no more. When I feel that we two meet in a perception, that our two souls are tinged with the same hue, and do as it were run into one, why should I measure degrees of latitude, why should I count Egyptian years?”
—Ralph Waldo Emerson (1803–1882)
“Complete courage and absolute cowardice are extremes that very few men fall into. The vast middle space contains all the intermediate kinds and degrees of courage; and these differ as much from one another as men’s faces or their humors do.”
—François, Duc De La Rochefoucauld (1613–1680)
“A petty reason perhaps why novelists more and more try to keep a distance from journalists is that novelists are trying to write the truth and journalists are trying to write fiction.”
—Graham Greene (1904–1991)