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Philosophy

Mereology: The Philosophy of Parts and Wholes

Quick fact

Mereology is younger than many branches of philosophy; it was formally developed by the Polish logician Stanisław Leśniewski in the early 20th century as an alternative to set theory.

Why this is interesting

A coffee mug is made of ceramic, but if you smash it into pieces, are those pieces still parts of the mug? What if you glue them back together? Mereology asks: when is something a part of something else, and when does a whole stop being that whole?