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:
“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)
“No sooner met but they looked; no sooner looked but they loved; no sooner loved but they sighed; no sooner sighed but they asked one another the reason; no sooner knew the reason but they sought the remedy; and in these degrees have they made a pair of stairs to marriage, which they will climb incontinent, or else be incontinent before marriage.”
—William Shakespeare (1564–1616)
“Ah, the truth, what a thing it is! I sacrifice so much for it, with people: I forego, for truth’s sake, discretion, loyalty, diplomacy, tact, polite manners, elegance, grace, poise, balance, good taste, conformity, image-role, fashionableness, polish, confidences, promises, ambition, consistency, identity, clarity, comprehensibleness, good will, hypocrisy, and lots of other things—amass sacrifice, at truth’s altar. God! is truth worth it? I hope it is. It better be, in fact.”
—Marvin Cohen, U.S. author and humorist. Fables at Life’s Expense, “Where Does Truth Lie,” Latitudes Press (1975)