I will introduce you to fuzzy logic, if you don't know about it:
First conventional logic, called (apt) crisp logic:
Ask a question: is he there in the room?, and answer could be Yes, No, or Don't know.
That's crisp logic. It is also called bivalued logic.
But, we all know that a day can be bright from zero to hundred %, and the night could be dark from zero to 100 %.
So, there is lot of gradation, and answers could be many: this is fuzzy logic. It is also called multivalued logic.
The humans knew this aspect for thousands of years, but didn't name it that way, and didn't define, until Prof. L. Zadeh did that some six decades ago.
There are many systems based on this fuzzy logic: one example is new generation washing machines; when the ladies washed the clothes in earlier times (and even now), they used inherently and unknowingly the basic aspects of fuzzy logic!
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