The Idea Of Form As An Idea In Art: Adapted From The Meaning Of A Literary Idea, By Lionel Trilling

Analysis (not mine) as poetry and as the essence of the meaning of poetry, i.e. what poetry is, albeit with some editing of the analysis by me:

The Idea Of Form As An Idea

Thus it can be said
the very form
of a literary work
is itself an idea.
Dialectic:
a developing series
of several stages,
the propriety,
the relevance,
of their
connections
among themselves:
we make judgments
of the implied purpose.

Dialectic is form in art
leading the mind
to some conclusion,
conducting the mind,
inevitably.

The form of drama
is itself an idea.
The form of the drama
is its idea.
And its idea
is its form.