Fuzzy Thinking in Science

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Students doing math in school learn about well defined sets.  They learn to discern whether something is or isn't in a set.  The number "two" is in a set of even numbers, and not in a set of odd numbers, and no number can be both even and odd.

Recently physicists and engineers started talking about fuzzy sets, where some things can belong to a certain degree in a set.  Fuzzy scientists think about questions that are matters of degree.  It's clear that you wouldn't put a four foot two inch man in a set of tall men.  But where does a five foot ten inch man fit?  Asians might not agree with North Americans about whether to put him in a tall set or not.

Any property like height, which is continuous, leaves us in a difficult situation.  If six foot is tall, how do we classify five foot eleven inches?

All this is not just philosophy, because engineers are using fuzzy sets to produce more flexible machines.  So, a fuzzy washing machine has an electronic eye that keeps track of a range of variables.  It adjusts its instructions in response to many quantities which come in degrees of difference.  How dirty is it?  How big is the load?  Similarly, smart TV's monitor and adjust the brightness and contrast of a shifting image.

So next time you are accused of fuzzy thinking, take comfort that today's scientists use fuzzy logic to deal with a world that is grey, rather than white and black.