of parts, but must also be of a certain magnitude; for beauty
depends on magnitude and order. Hence a very small animal organism
cannot be beautiful; for the view of it is confused, the object
being seen in an almost imperceptible moment of time. Nor, again,
can one of vast size be beautiful; for as the eye cannot take it all
in at once, the unity and sense of the whole is lost for the
spectator; as for instance if there were one a thousand miles long.
As, therefore, in the case of animate bodies and organisms a certain
magnitude is necessary, and a magnitude which may be easily embraced
in one view; so in the plot, a certain length is necessary, and a
length which can be easily embraced by the memory. The limit of length
in relation to dramatic competition and sensuous presentment is no
part of artistic theory. For had it been the rule for a hundred
tragedies to compete together, the performance would have been
regulated by the water-clock- as indeed we are told was formerly done.
But the limit as fixed by the nature of the drama itself is this:
the greater the length, the more beautiful will the piece be by reason
of its size, provided that the whole be perspicuous. And to define the
matter roughly, we may say that the proper magnitude is comprised
within such limits, that the sequence of events, according to the
law of probability or necessity, will admit of a change from bad
fortune to good, or from good fortune to bad.
Unity of plot does not, as some persons think, consist in the
unity of the hero. For infinitely various are the incidents in one
man's life which cannot be reduced to unity; and so, too, there are
many actions of one man out of which we cannot make one action.
Hence the error, as it appears, of all poets who have composed a
Heracleid, a Theseid, or other poems of the kind. They imagine that as
Heracles was one man, the story of Heracles must also be a unity.