The beautifullness and ugliness are opposites; unless you know what is ugly, you cannot appreciate beauty; the two are polars, and exist in a relation to each other; this is very well represented by the so called fuzzy logic; we can represent these on the scale of the membership function; 0% to 100%; so if something is 10% ugly, then it is 90% beautiful, and if it is 10% beautiful, then it is 90% ugly; so fuzzy logic depicts clearly the relativity and polar relationship of all the opposites in this world.
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So, on the same scale, my belongingness to the membership function of old people is 75%, and 25% to the membership function of the young people.
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So, a child's membership function value is, say 95% in young age, and 5 % in the old age (may be that is why it is called a five year old child!).
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