Biographa Literaria, which literally means "Literary Biography," was written by the Romantic Period poet Samuel Taylor Coleridge, and the full title is Biographia Literaria; or, Biographical Sketches of My Literary Life and Opinions (1817). This work, which is very dense and often difficult to understand, is Coleridge's discussion of the nature of poetry and the creative process.
For Coleridge, and the same is essentially true for Wordsworth, the creation of poetry requires the poet to bring all his senses, intellect, and soul together in order to create a poem that exhibits rational and imaginative thought; emotions; philosophy and innocence; and truth.
Even more important is his analysis of the role of the imagination in poetic creation. Coleridge argues, in essence, that the imagination is made up of two components: an understanding sensory perceptions, which are familiar to the poet, and the perception of universal truths (not understood the way perceptions are) but perceived intuitively as truths, for example, perceiving the concept of truth itself and understanding the nature of God. The poetic imagination, then, is a combination of understanding one's sensory perceptions and the intuitive understanding of abstract truths that one has not experienced by perceives anyway.
In the Biographia, Coleridge praises Wordsworth's poetry as the highest manifestation of poetic imagination as Coleridge defines it.