Other arguments in Book I include proof by contradiction that all cannot be one and that all principles must be contraries or the product of contraries.  
This work begins with the observation that children will first call all men "father" and all women "mother" before coming to distinguish particular people. Other arguments in Book I include proof by contradiction that all cannot be one and that all principles must be contraries or the product of contraries.  The most important of the eight total books is Book II where the author questions why planting a wooden bed doesn't result in the growth of a bed-tree. The fact the tree is made of wood explains material composition dictates an inner principle of change or motion. This contributes to the definition of "nature" that is used to explain another central concept that comes in 4 types, including "efficient" and "final."  FTP, identify this work best-known for categorizing the "causes," a book by Aristotle.
This work begins with the observation that children will first call all men "father" and all women "mother" before coming to distinguish particular people.
Physics