The question of beginnings and endings--how many of them to have and where to put them--has troubled many authors. Indeed, some have seen the singular linear path of traditional literature as cause for consternation. This is expressed by the narrator in Flann O'Brien's At Swim-Two-Birds (1968):
One beginning and one ending for a book was a thing I did not agree with. A good book may have three openings entirely dissimilar and inter-related only in the prescience of the author, or for that matter one hundred times as many endings. (1)
At Swim-Two-Birds opens with three beginnings and proceeds to follow the third for the space of a few pages. Later in the work the reader again encounters the same text from these beginnings mingled amongst the various narrative pathways.
In At Swim-Two-Birds, the linear structure of the printed page does not constrain the author to a linear narrative. The reader of the book must mentally order the scenes and draw connections between them to save the book from being condemned as nonsense. The non-linear nature of At Swim is emphasized more than it would be if the same material were presented as a hyperbook, where the reader might expect a degree of multiplicity.
O'Brien's work may also be listed with those that attack the conventions of the realist novel. As Anne Clissmann writes in Flann O'Brien: A Critical Introduction to his Writings:
At Swim was intended to be a book which would overturn and expose the conventions of literary creations. It is as Vivian Mercier described it in The Irish Comic Tradition, "an assault on the conventions of all fiction, but especially on those of the so-called "realistic" novel. At Swim is in fact, an anti-novel [...]. (89)
O'Brien not only multiplied the number of beginnings and endings, he multiplied the number of authors, at times writing under the names of Myles na gCopaleen, John James Doe, George Knowall, Brother Barnabas, and the Great Count O'Blather. All were pseudonyms; his real name was Brian Ó Nualláin which was anglicised as Brian O'Nolan.