think to be not without a meaning. A Plot, therefore, of this sort is
necessarily finer than others.




10


Plots are either simple or complex, since the actions they represent
are naturally of this twofold description. The action, proceeding in
the way defined, as one continuous whole, I call simple, when the
change in the hero's fortunes takes place without Peripety or
Discovery; and complex, when it involves one or the other, or both.
These should each of them arise out of the structure of the Plot
itself, so as to be the consequence, necessary or probable, of the
antecedents. There is a great difference between a thing happening
_propter hoc_ and _post hoc_.




11


A Peripety is the change from one state of things within the play to
its opposite of the kind described, and that too in the way we are
saying, in the probable or necessary sequence of events; as it is for
instance in _Oedipus_: here the opposite state of things is produced
by the Messenger, who, coming to gladden Oedipus and to remove his