Sometime during the fourth century, in northwest China, a woman named Su Hui picked up her silk thread and embarked on an embroidery project. The result was an extraordinary work of visual poetry – a grid of 29 x 29 characters, shuttle-woven on brocade to form a palindrome poem that would become known as Xuanji Tu, or the ‘Star Gauge’.
According to legend, the poem had a romantic origin. Su Hui’s husband Dou Tao, a high-ranking government official, was exiled to a remote desert post, taking with him a concubine. Grief-stricken, Su Hui refused to accompany him and the ‘other woman’. Instead, she wrote the ‘Star Gauge’ as an expression of her love and a plea for him to return. It is a magnificent example of what is known in Chinese literature as a ‘reversible poem’, which can be read from top to bottom (starting at the top right) or in reverse order from bottom to top. Such poems are made possible by the fact that Chinese characters can be read in any direction and can function as any part of speech.
The structure of the ‘Star Gauge’ is, however, considerably more complex than mere reversibility. Five colours of silk used in the embroidery serve as keys to different routes through the poem. The outer border consists of a single circular poem and within the grid of characters there are pathways to thousands of shorter poems. In his 2012 article ‘Welling out of Silence’, David Hinton discusses the poem’s structure and place in Chinese tradition; his translation of a segment of the poem may be read here.
The Star Gauge Project gives a sense of the poem’s richness and complexity. Initiated at Norwich University in 2015, the project is an interactive depiction of the poem where you can hover the cursor over each character to discover its pronunciation and range of meanings in English.
Apparently, the poem succeeded in its objective: upon reading it, Su Hui’s husband left his concubine and returned to his first love.
Well over a millennium later in Renaissance England, the poet Henry Lok also composed an ingenious grid poem. Lok’s poem, written in 1597, consists of ten lines, with ten words in each line. It was addressed to Queen Elizabeth 1.

The poem can be read in the conventional way, line by line. However, choosing different starting points and routes through the word square reveals an intricate substructure of shorter poems.
For example, reading the shaded region (representing the Cross of St. George) in a certain sequence gives:
Rare Queen, fair, mild, wise Shows you proof For heavens have up held Just world’s praise sure. Here Grace in that Prince of earth’s race, whom There shields thus God whom choice (rich Isle, stay!) builds.
Further sub-structures within the poem are discussed here.
In the 1960s François Le Lionnais, co-founder with Raymond Queneau of the Oulipo movement, devised the concept of a multiple-choice narrative which allows the reader to select a path through a story or poem from a range of possible options. Queneau’s ‘Cent mille milliards de poémes’ (‘A Hundred Thousand Billion Poems’), which he published in 1961, is a sequence of ten sonnets constructed in such a way that any given line from one sonnet can be interchanged at random with the corresponding line from any of the other sonnets. The dedicated reader therefore has a choice of 1014 poems, which you can explore (in the original French, or an English translation) at Beverley Charles Rowe’s brilliant interactive site. Set aside some time – it will take you around 200 million years to read all the poems!
‘Multiple Choice’, by the American Oulipian poet Harry Mathews, invites the reader to make judgemental decisions about the course of his lead character’s relationships. The poem can be read on JoAnne Growney’s website Intersections – Poetry with Mathematics, together with Growney’s neat representation of the narrative structure as a decision tree.
Mike Naylor’s visual poem ‘Decision Tree’, shown below, is not only a multiple-choice poem but also a fractal.

Mike Naylor provides a thoughtful discussion on the poem’s structure in a blog post which you can read here.
Mathematically, a tree is a type of graph (graph theory is an area of study in discrete mathematics). A digraph, also known as a directed graph, is another type of graph which has found applications in poetry. In their paper ‘The Poetics of a Cyclic Directed Graph’, Courtney Huse Wika and Daniel May discuss the creative possibilities of composing poetry based on a digraph structure, illustrated with a fine example of the form by Dr. Huse Wika. As the authors note, ‘Writing along the digraph construct naturally lends itself to lyric free-verse. While it would be difficult to craft a strictly descriptive poem because the poem’s multiplicities would likely deny a coherent, concrete message, it still offers natural structures for the remaining two rhetorical modes in poetry: argument (where the speaker proffers a theory or stance and proves it with poetic evidence) and narrative (where the speaker crafts a story with all of the required narrative elements: exposition, rising action, crisis, falling action, and resolution).’
Daniel May’s elegantly crafted poem ‘What the Body Does Next’ has a complex cyclical structure, with inter-linked sections that may be read in any order. The digraph form is perfectly matched to the poem’s subject matter of living in pandemic times.
Online journals can give opportunities for experimentation and playful formatting that cannot be replicated on the written page. Voidspace, a recent arrival on the digital scene, provides an exciting platform for interactive work. Its inaugural issue contains some stunningly innovative contributions, such as Faultlines by Mark Ward which offers a succession of choices and is as much a computer game as it is a poem. In ‘Faultlines’, as in life, we do not get to see the outcome of our choices in advance. The ‘true ending’ is only reached when there are no more options left to play.
Su Hui’s grid poem ‘Star Gauge’ was shuttle-woven on brocade in the 4th century, while Henry Lok’s grid poem was type-set and printed in 1597. To conclude, here’s a 2021 version of the grid poem by G. P. Hyde, presented within a digital framework. ‘The idea’, Hyde writes, ‘is that you can read it in any order but going either left to right or top-to-bottom you can access a range of different meanings.’

We can all do with more kindness in our lives!
With thanks to Mike Naylor, Courtney Huse Wika, Daniel May, Mark Ward and G.P. Hyde for their kind co-operation, and for generously granting permission to reproduce their work.
Further Reading
Henry Ace Knight, An interview with Jen Bervin in Asymptote Journal. Available at https://www.asymptotejournal.com/interview/an-interview-with-jen-bervin/
Jen Bervin, Su Hui: interviews with Wenwen Zuo, Lan Yu and Jin Wen. Available at https://vimeo.com/245213672
Marian Christie, From Fibs to Fractals: exploring mathematical forms in poetry. Beir Bua Press, 2021.
Philip Terry (ed) The Penguin Book of Oulipo. Penguin Random House UK, 2019.