The Monstrosity is contrary to Nature,
not contrary to Nature taken absolutely but
contrary to the most usual course of Nature,
which is both eternal and essential.
Aristotle 4th century BC
Comment: many theories focused on the "nature" of "monstrosity" - the malformed were seen as a manifestation or portent of the gods, or as a new species, or as a signal of hybridity (result of bestial intercourse) - such notions ended in the heap of trash of wrong convictions. An exception is Aristotle who 4,000 years ago correctly concluded that all malformations are departures from the normal.