fuzzy logic

Fuzzy logics are one of the forms of fuzzy reasoning. They assign levels of 'truth' to varables rater than the dichotomous true/false of Boolean logic. This is used to capture the levels of uncertainty we have in real life about many things. So, for example, we might have:

    is_summer=1 – definitely true

    feel_like_break=0.7 – more true than not

    will_stay_fine=0.2 – closer to false (UK weather!)

Logical operators AND and OR are converted into max and min , which correspond to the normal logic meanings for true/false values. We can then create a rule such as:

    go_for_a_picnic   =   is_summer AND ( feel_like_break OR will_stay_fine

        =   min ( 1, max( 0.7, 0.2 ) )   =   min(1,0.7) = 0.7