The fable of every poem is, according to Aristotle’s division, either simple or implex. It is called simple when there is no change of fortune in it; implex, when the fortune of the chief actor changes from bad to good, or from good to bad. The implex fable is thought most perfect: I suppose, because it is more proper to stir up the passion of the reader, and to surprise him with a greater variety of accidents.
noun
A genealogical coefficient of a given genealogical tree; defined as the difference between the number of theoretical ancestors of a person and the number of his/her real ones in a given generation (the degree of pedigree collapse).