Introduction to Poësy Matters and Other Matters

This book represents the first major text survey of writing and thought by Swedish musician, visual artist, and mathematician Catherine Christer Hennix. The writings contained in these two volumes were written from the early 1970s through 2016—in some cases, with revisions in 2017 and 2018—and draw on a wide range of references, including formal logic, intuitionist mathematics, modal music, topos theory, cybernetics, medieval Japanese theater, Islam, psychoanalysis, and the specifics of Hennix’s own intermedia practice. These writings alternately—and sometimes simultaneously—take the form of poetry, drama, musical composition, and prose essays. While this collection is extensive, it is in no way comprehensive; rather, it is a first attempt to introduce Hennix’s immense, diverse, and under-acknowledged body of written work to a larger public. This effort, which coincides with Hennix’s similarly overlooked music and visual art, has been reaching wider audiences in recent years through numerous exhibitions and newly released recordings. We hope that this two-volume set—comprising Poësy Matters, which focuses on Hennix’s poetry and drama, and Other Matters, which, in prose, focuses on her art as well as topics like psychoanalysis and mathematics—will give readers a glimpse into the complexity of Hennix’s thought, which has staked a singular position throughout the past fifty-plus years. These two volumes will also allow readers to reimagine some of the artistic and historical narratives and lineages in which Hennix played an active part during this timeframe.

Poësy Matters and Other Matters is split into four total sections across the two volumes: in Poësy Matters, poetry and abstract No dramas the latter section titled “Theater of the Eternal Mind”); and in Other Matters, program notes and essays appear in one section, and the other section hosts the self-contained work The Yellow Book. With the exceptions ofPoetry as Philosophy, Poetry as Notation (1985), The Yellow Book (1989), Mysterium Fascinans (1992), ▢κ (Excerpt from Notes on the Composite Sine-Wave Drone Over Which The Electric Harpsichord is Performed) (2010) and The Electric Harpsichord (2010, written by Henry Flynt), the texts included within the volume have not been previously published for wider audiences, and most have never been published at all, though some—namely Notes on Toposes & Adjoints (1976), Brouwer’s Lattice (1976), and selections from Ṭarīqah Nūr-Samad (2013–16)—were published in small editions as mimeographs or printouts to accompany exhibitions or performances. Even when published, many of Hennix’s writings were only preliminary drafts, in need of further work, which has made her reluctant to reprint them.

The texts included here only represent a small selection of Hennix’s written oeuvre. Many of her writings have been lost over time; others, meanwhile, have been purposefully excluded from this collection because Hennix has deemed them failures. Although she is a prolific writer, she considers the majority of her work unfinished and unsuitable for publication. Some of the texts collected in these volumes are reproduced as they first appeared in their own time (with minor edits for typographical and grammatical mistakes), while several other texts have been significantly revised by Hennix, sometimes with this collection’s editorial team and with Hennix’s longtime collaborator, Henry Flynt. All but two pieces have been typeset according to this collection’s layout; the two exceptions—Notes on Toposes & Adjoints and The Yellow Book—are printed as facsimiles of their original publication, with minor corrections for content and quality. We have noted each text’s history on its own title page.

The work included here represents some of Hennix’s most significant contributions to the numerous discourses in which she has been involved over the last fifty years, with a special focus on her creative writing as it relates to her work as a musician and visual artist. While Hennix’s work in mathematics has played an important role across disciplines, we have not included any of her purely mathematical writings. Hennix’s writing creates a concatenation of complex abstract thought that is also reflected in her art installations, which utilize a variety of mediums and forms—both visual and auditory—which the viewer is expected to navigate seamlessly. Hennix does not necessarily consider her paintings or sculptures “art”; her work collapses these fields, often presenting mathematical concepts in the form of paintings or drawings —as is the case with Algebraic Aesthetics (1973–75) and, later, Algebras w/ Domains (1973­–­91) and Triptyque Lacanien (1975­–91)—or, through her use of Brouwer’s principles of intuitionism, as a method for framing her musical compositions and work with her ensembles, such as the Deontic Miracle and, more recently, Chora(s)san Time-Court Mirage.1 Similarly, in her writing, Hennix places fragments and formulations in juxtaposition, each piece acting as a supplement to its partner, often with the order of a certain text possessing a variable component.

One of the primary difficulties in approaching Hennix’s work, both as a reader and as an editor, is the machination of her cross-disciplinary approach to thought. The Yellow Book—one of the few pieces collected here that has been published in (slightly) wider circulation, as part of a special issue of the journal IO dedicated to the thought of Hennix, Henry Flynt and, to a lesser extent, Alexander Sergeyevich Yessenin-Volpin, edited by the poet Charles Stein, titled Being = Space × Action: Searches for Freedom of Mind through Mathematics, Art, and Mysticism—is perhaps the clearest example of Hennix’s working method in written form, given the variation in writerly approach and discursive material from page to page. But this method of variegation is reflected in all of her work, not just on a formal level but also, simply, through the interconnected nature of her diverse pursuits. Her background in different disciplines and her unique writerly voice manifest themselves in idiosyncratic forms of personal notation and crop up throughout Hennix’s writings; the notes draw from topos theory, formal languages, psychoanalytic formulas, and predicate calculus as means of articulating internal subjective states. An example of this use of notation can be found in Notes on Toposes & Adjoints(1976) or, more specifically, her diagramming of Dutch mathematician L.E.J. Brouwer’s concept of “two-ity,” which describes the Creative Subject’s ability to unite discrete events within a continuous flow of time. Originally created for an exhibition at the Moderna Museet, Stockholm, Hennix’s diagram was not published until 1989—as part of the The Yellow Book—and is a prime example of her working method.

• 1Hennix’s dating of her work often follows the year when she conceived of the concept and recorded it in her notebook. In the case of the Algebraic Aesthetics, which Hennix considers to be a mathematical concept and not necessarily a work of art, the black-and-white decidable word problem was originally conceived in 1973, and the four-color undecidable word problem was conceived in 1975. Both pieces were meant to be included in some capacity in Hennix’s 1976 exhibition at the Moderna Museet but were not executed and shown until 1979, as works on paper. The images later appeared in a series of paintings made for the Museum Fodor, Amsterdam, in 1991 called Algebras w/ Domains, dated 1973–91, and C-Algebra w/ Undecidable Word Problem, dated 1975–91. Hennix and I continued with this dating model for the 2018 retrospective “Catherine Christer Hennix: Traversée du Fantasme” at the Stedelijk Museum, Amsterdam.

In May of 1968, Catherine Christer Hennix, a twenty-year-old musician and student living in Stockholm, traveled to New York in hopes of visiting galleries. But upon arrival, she learned that all the galleries were closed for the summer. Her trip wasn’t fruitless, however. Earlier that year, Hennix had published a score titled Identitäten II on Åke Hodell’s Kerberos imprint, which she describes as a “sound and picture poem.” Hodell had sent copies to Dick Higgins—founder of the intermedia, Fluxus-affiliated publishing company Something Else Press—and Hodell helped to arrange a meeting between Higgins and Hennix while the latter was in New York. Higgins invited Hennix to stay in the loft above Something Else Press’s office, then located on 22nd Street behind the Chelsea Hotel in Manhattan. Through Higgins and his partner, Alison Knowles, Hennix would quickly meet a number of artists associated with—or adjacent to—Fluxus, including composers and artists like John Cage, James Tenney, Philip Corner, and Walter De Maria.

Infatuated with New York, Hennix returned to the city every few months in the years after her first visit and became actively engaged in a community of downtown artists. During this time, she produced an incredible body of work across a variety of media, most significantly as a composer and musician but also as a prolific writer of theory and poetry, a painter, and a sculptor (though, as mentioned before, Hennix considers her own painting and sculpture to function best outside the traditional framework and discourse of the visual arts). The majority of Hennix’s work from this period—and all others—has only been seen or heard by small audiences, and rarely even by her closest friends and colleagues. Today, despite the legendary status of many of her contemporaries, little is known about Hennix’s own practice and history.

In Sweden, in the mid-1960s, Hennix had been pursuing a degree in biochemistry at Stockholm University, but she shifted focus due to her inability to perform the animal dissections that the major required. Because of her interest in music, and with recent research and developments in the field of speech synthesis, it was suggested that she study something else; Hennix chose linguistics. Noam Chomsky and Morris Halle’s groundbreaking phonology study, The Sound Pattern of English, published in 1968, would prove to be an important touchstone for Hennix’s very early work. After spending some time in the linguistics department at the University, she also studied philosophy under Anders Wedberg and would later formally switch to logic and mathematics.

These diverse academic studies complemented Hennix’s deep studies in music. When she first arrived in New York, she was already a seasoned jazz drummer who had been playing with her older brother Peter since she was five. Growing up in Stockholm, Hennix had many opportunities to hear jazz luminaries such as Cecil Taylor, John Coltrane, and Archie Shepp, when they gigged at the famed venue the Golden Circle; Hennix also heard this music through her mother, Margit Sundin-Hennix, who was herself a jazz composer and a patron of the arts. As a teenager, Hennix met many well-known musicians—including Sonny Stitt, Dexter Gordon, Eric Dolphy, and Albert Ayler—some of whom stayed at the family home and would play impromptu sessions with Hennix. She later took formal music lessons with the legendary trumpeter Idrees Sulieman, who lived with Hennix’s family for part of the ’60s.1

While Hennix had a serious interest in jazz—something which informs her work to this day—she was also engaged in other forms of avant-garde music at a young age, notably as an early member of Stockholm’s pioneering Elektronmusikstudion (EMS) under the direction of Knut Wiggen. At EMS, Hennix worked as a composer on early mainframe computer and electronic music, producing some of the first Text-Sound Compositions. The term “Text-Sound Composition” has its origins in the concert An Evening of Text-Sound Compositions, organized and featuring works by Hodell, Lars-Gunnar Bodin, and Bengt Emil Johnson at the Moderna Museet in April of 1967.

Fylkingen, the former chamber music society and contemporary music venue and organization whose linguistic arts wing was newly under the direction of Johnson, Bodin, and the poet Sten Hanson, continued this initiative with a series of festivals in Stockholm called the Text-Sound Festival. Running from 1967 until 1977, the festival showcased new work being created at EMS alongside the work of international sound poets including Bernard Heidsieck, François Dufrêne, Henri Chopin, and Bob Cobbing, who were employing strategies used by concrete musicians such as Pierre Schaeffer and Pierre Henry. Hennix participated in the second Text-Sound Festival, which took place April 21–24, 1969, at the Moderna Museet. Her short composition Still Life, Q* (1969) would be anthologized on Text-Sound Compositions 5 1969 (Sveriges / Fylkingen, 1969) that same year and is one of the few pieces that she made at EMS that has survived. While Hennix’s work from this period is perhaps more abstract than that of her contemporaries, she still explicitly engaged the use of language and its transformation and decomposition through her interest in Fourier analysis.2  Identitäten II, the piece published by Hodell—whom Hennix had met through EMS—also has an affinity with the prevalent avant-garde music of its time while retaining a unique approach and subject matter. Like John Cage’s Fontana Mix (1958), Identitäten II utilizes transparencies that can be layered over one another to create variations. The cross-disciplinary work Hennix had already created by the age of twenty prepared her well for the diverse New York scene and would foreshadow the resultant, implacable body of work she has developed since.

• 1Hennix’s mother was a songwriter and a friend and collaborator of Sulieman. Her work can be heard on the 1964 Idrees Sulieman and Jamila Sulieman album The Camel, published in Sweden by Columbia Records.
• 2Fourier analysis, or Fourier synthesis, is named after the mathematician Joseph Fourier, who discovered that any wave pattern can be broken up into smaller, simpler waves. These simpler waves are called sine waves after the mathematical function that describes them. Fourier analysis is his system for determining these simple wave- forms. It has played an important part in Hennix’s music from her time at EMS.

In 1969, in New York, Hennix met the composer La Monte Young; later, through Young, she met two other figures with whom she would work in the ensuing years: the musician and philosopher Henry Flynt and the Hindustani classical singer Pandit Pran Nath. After her initial meeting with Young, Hennix stayed with the composer for over a week. Absorbed in his music, she began an intensive process of writing about the theory of his work, which would also inform the parameters of her own practice moving forward. In 1970, she invited Young and his partner, the musician and visual artist Marian Zazeela, to Stockholm. While in Stockholm, Young and Hennix would create a realization of Young’s 1969 composition Drift Study using phase-locked sine-wave generators, a new technology that EMS happened to have.

At Young’s encouragement, in 1970 Hennix traveled to Fondation Maegh, located in Southern France, outside of Nice, to see a performance by Pandit Pran Nath. She visited Pran Nath again in 1971 and became the singer’s disciple in a ceremony in San Francisco, where Pran Nath was teaching a class with Terry Riley at Mills College. In addition to the broader Bay Area being a hub for musicians and artists, University of California, Berkeley—along with neighboring universities such as Stanford and UCLA—was the center of a burgeoning logic and mathematics community. While in the area, Hennix became an exchange student at Berkeley under the logician and mathematician Alfred Tarski, a friend of her former Swedish philosophy professor Wedberg. Tarski at the time was one of the leading names in logic and mathematics, making significant contributions to model theory, algebraic logic, topology, and set theory, all of which would play central roles in Hennix’s work.

Serious pursuit of these studies while working with Young and Pran Nath led Hennix to start her own just-intonation ensemble the Deontic Miracle, in 1971, with her brother Peter performing on Renaissance oboe and Hans Isgren, who also, notably, played sarangi on Don Cherry’s Organic Music Society (Caprice, 1972).1  Hennix understood her work with the Deontic Miracle to be very much in the style of Young while also as drawing more directly on both Japanese gagaku music (which Young had also studied in the early ’60s) and the early vocal music of the late-Middle Ages composers Perotinus and Leoninus. While Hennix was certainly inspired by Young’s Theatre of Eternal Music, her goal was not to imitate but, rather, to create work that would demonstrate that Young’s musical concepts were general enough to allow musicians to take many different paths through them. The name of Hennix’s ensemble, the Deontic Miracle, pessimistically refers to the miraculous nature of the group’s ever getting a chance to perform; true to their name, they only had one official gig, at the Moderna Museet in Stockholm in March of 1976.

Today, Hennix is known primarily for her seminal composition The Electric Harpsichord, which was originally performed on March 23, 1976, at the Moderna Museet. The recording of the composition—a fragment of the performance, just under twenty-six minutes long—was made as part of Brouwer’s Lattice, a ten-day festival of new music organized by Hennix and the Swedish curator Ulf Linde as a showcase for Hennix’s own compositions and the work of three of her contemporaries: Young, Riley, and the lesser-known saxophonist and pianist Terry Jennings. The Deontic Miracle performed and recorded over the course of the ten days, but Hennix shelved the tapes. The tape that became The Electric Harpsichord (at the time of the exhibition, Hennix was referring to the work as The Well-Tuned Harpsichord) would certainly not be known to us today if it were not for the advocacy of Henry Flynt, who discovered the recording in a “satchel of documentations [that Hennix left] in [his] apartment” in 1977.2  As Flynt tells the story in a text about the piece, he took the tape out of the satchel, played it, and was “immediately floored by what he heard.” Over the next couple of years, Flynt would present the tape at various venues in New York, including at WBAI-FM in 1977, at Phill Niblock’s Experimental Intermedia in 1978, and then, finally, at the Kitchen in 1979 along with two of his own compositions in the genre of what he had recently named—in response to

The Electric Harpsichord—hallucinogenic/ecstatic sound environments. The program at the Kitchen included Electric Harpsichord #1 and Stereo Piano #1 (1978), a piece attributed to Hennix in the press release though she just performed piano under Flynt’s direction; and Flynt’s Glissando #1 and Celestial Power.3

The press release for the show at the Kitchen—included in volume two of this collection, Other Matters, alongside Hennix’s κ(Excerpt from Notes on the Composite Sine-Wave Drone Over Which The Electric Harpsichord is Performed)—hints at the expansive conceptual framework that undergirded her practice at the time. It also refers to Hennix’s interest in the intuitionist mathematics of Brouwer, her explorations of the relationship between “modal music and states of consciousness,” and Flynt’s own version of the hallucinogenic/ecstatic sound environments (the use of “aural illusions which produce logically impossible or unnameable perceptions”—the aural equivalent of Flynt’s ongoing interest in perceptual and logical anomalies). Other Matters also includes some subsequent writings on The Electric Harpsichord to highlight the work’s historic importance for both Hennix and Flynt.

• 1In addition to performing with Don Cherry, Hans Isgren also produced a number of records of Indian musicians over the course of the 1970s, including Pandit Ram Narayan, Ustad Amjad Ali Khan, Ustad Zia Fariduddin Dagar, and Pandit Nikhil Banerjee.
• 2From Henry Flynt, “The Electric Harpsichord,” included in volume two of this collection.
• 3Flynt recounts this story in detail in his liner notes for the The Electric Harpsichord, originally published in 2003 by Etymon Editions and reproduced in Other Matters (Blank Forms Editions, 2019).

In the fall of 1976, soon after Brouwer’s Lattice, Hennix presented the solo exhibition “Toposes & Adjoints: Survey of Abstract Concept Formations from Cantor to Lawvere,” consisting of an installation called (E-) environment, at the Moderna Museet, comprising steel sculptures, sine wave compositions, paintings, projected images, and a mimeographed handout called Notes on Toposes & Adjoints. Just as Hennix’s music is concerned with invoking specific states of consciousness in the listener, “Toposes & Adjoints” showed Hennix working across a number of interrelated compositional modes, creating a total environmental installation that imagined the viewer within the framework of Brouwer’s concept of the Creative Subject. In her writing at this time, as collected in Notes on Toposes & Adjoints, we see a specific interest in mapping these internal subjective states; Hennix, in turn, is creating models and terminology— such as “homosemeiosis”—as ways of thinking through what it means for one to experience the (E-) environment as a thinking subject. Two particular sections of Notes on Toposes & Adjoints— “Spectra of Modalities and The Theory of the Creative Subject, Th(Σ)” and “Semiotics”—use a highly abstracted language to map out subjective internal states. In these texts, Hennix’s interest in the internal, privatized aesthetic experience resonates with Flynt’s famous notion of Concept Art—but, though Hennix sees her work within this continuum, she makes an important qualifying reversal of Flynt’s original assertion that Concept Art is purely syntactic. What Hennix begins to call Epistemic Art (or E-art) relies heavily on semantics—instead of syntax—opening up a space for the production of meaning, not unlike the language of the unconscious in analytic discourse. This conversation plays out in two texts printed in this collection: Philosophy of Concept Art: A Conversation with Henry Flynt (1989, 2011) and Mysterium Fascinans: The Epistemic Art of Catherine Christer Hennix (1992), a piece written by the curator of “Toposes & Adjoints,” Ulf Linde, with comments by Hennix, for a catalog published after the run of a group show at Fodor Museum in 1991.

As I have already suggested, the years around 1976 were extremely productive for Hennix. In addition to leading her band and creating two exhibitions, she was studying with Pran Nath, continuing to pursue her degree in mathematics and logic, writing poetry, and producing her first abstract Nō  dramas—an experimental form of writing based on traditional Japanese Nō that she would continue to work on through the early 2000s.1  Her first five dramas, written in the early to mid-1970s, would be privately anthologized and commented upon by Flynt in 1985; an updated version of Flynt’s essay is included as an introduction to the text in volume one of this collection, Poësy Matters. In addition, Hennix’s original Nō dramas, Ankoku Butō-No-Soshi (Tatsumi Hijikata in Memoriam) (1986) and To Snatch from the Moon with the Hand (1999) and One Dark, Two Darks (2002), will be included, thereby collecting all of her work in this form. With the exception of Ankoku Butō-No-Soshi, which is included as a section in The Yellow Book, none of these works has been published before. Flynt’s commentary—also previously unpublished—remains the most extensive analytical and descriptive text on this work to date.

When Hennix began writing these texts, Japanese Nō had already been a part of the vocabulary of the European avant-garde for several decades, since the 1916 publication of Ernest Fenollosa and Ezra Pound’s collection and translation of classic plays. However, in its transfer to the West, Nō suffered many reductions of its transformative powers and was often appreciated by writers like Pound only so far as it reflected their own interests and mirrored the content of existing work.2  Hennix became acquainted with European-style Nō as a high school student when she attended the Swedish dancer Karin Thulin’s staging of classical warrior play Kagekiyo, generally attributed to Zeami Motokiyo, at Marionetteatern in Stockholm. Although Tulin’s staging was almost barren and devoid of many of the traditional elements of Japanese Nō, her deliverance of the role of Kagekiyo left a lasting impression on Hennix. After that event, she went on studying the translations of Nō by Fenollosa and Pound, Arthur Waley, and others.

In the library at the University of Stockholm, she found a translation of Motokiyo’s Kadensho—his treatise on Nō—which would become significant to her own work.3

Hennix’s own, less than straightforward presentation of what she considers her “European flavor of Nō” is inspired by her reading of these texts, but it is also clear that she is tapping into then-current avant-garde literature, poetry, theatre, cinema, music, and art, as well as her interest in set theory and mathematics—specifically her mobilization of the empty set—in these plays. The five early Nō dramas are centered around a series of the characters’ failed attempts at seeking enlightenment, which is simply the emptiness that surrounds them that they fail to recognize. The paradox here is that the action, by being emptied of the intended result (enlightenment), might as well have been a non-action (or the empty-action), which would have simply left everything as it was. In these plays, Hennix attempts to think about the concept of emptiness as both multidimensional (mathematical) and multicultural (through her appropriation of traditional Japanese Nō seen through the Western eye), in part by combining modern set theory with Buddhist ontology without any discrimination.4  That is, there is no exact precedence for Hennix’s “style”—the reader is on her own and is also the “creator” (creating subject) of the imaginary staging, provided that the text is read as a film script as opposed to acted out. In other words, all the props needed for any purpose are instantaneously available by the faculty of imagination. Hence, these dramas have every potential to defy reality.

Throughout the 1970s, Hennix traveled between New York, Boston, Stockholm, and San Francisco. In 1973, through a chance encounter with Maryanne Amacher in San Francisco, Hennix would be personally introduced to Alexander Yessenin-Volpin, the poet, human-rights activist, and mathematician (one of the few who would take the later intuitionism of Brouwer seriously) developing what would become known as ultra-intuitionism.

Yessenin-Volpin had recently fled the Soviet Union and was teaching at Boston University while Amacher was a fellow at Massachusetts Institute of Technology’s Center for Advanced Visual Studies in Cambridge; the two had connected through mutual friends. Hennix traveled back to Boston from San Francisco with Amacher to meet and study with Yessenin-Volpin. Hennix became his primary student and, eventually, his mathematical partner, producing a number of papers with him—most notably “Beware of the Gödel-Wette Paradox” (2002)—until his death in 2016. Hennix’s work in mathematics is extensive and also largely unpublished.

Hennix returned to New York State in 1978 for a position as a professor in the departments of mathematics and computer science at SUNY New Paltz. At the end of that year, Hennix had a small exhibition at Redbird, Sharon Avery’s apartment gallery in Brooklyn, where she presented the first iteration of her Algebraic Aesthetics as two small works on paper (a concept that had been developed for, but not included in, “Toposes & Adjoints”). The Redbird exhibition would prove to be a disaster: Hennix repudiated the opening and the work, sneaking in and out of the exhibition space and refusing to admit that she was the artist, eventually hiding out in Yoshi Wada and Barbara Stewart’s loft on Mercer Street.5  Hennix would not make another exhibition again for more than ten years. The work shown at Redbird consisted of a series of black-and-white and color equations that presented a mathematical concept: a decidable and an undecidable semigroup—a work of art. The work, purchased by Henry Flynt, would be later reproduced as part of The Yellow Book and, again in 1991, in a series of paintings for the Museum Fodor exhibition mentioned above.6  In this collection’s facsimile of The Yellow Book, we have reproduced an updated version, corrected with the assistance of Hennix, that is in line with her original vision for the piece.

Hennix taught for a year in New Paltz and then became a fellow with no course load the following year. During this time, she would occasionally travel back to Boston, at Marvin Minsky’s invitation, as a visiting professor of logic at MIT’s Artificial Intelligence Laboratory. She was still actively studying with Yessenin-Volpin, continuing her ongoing conversations and work with Flynt, and writing poetry, some of which is printed in this volume.

• 1Around this time, Hennix transferred from Stockholm University to Uppsala University in Sweden, where she clashed with her advisor over her involvement in the human rights movement.
• 2Ernest F. Fenollosa with Ezra Pound, ‘Noh’ or Accomplishment: A Study of the Classical Stage of Japan (London: Macmillan and Co., 1916).
• 3 Arthur Waley, The No Plays of Japan (London, George Allen & Unwin: 1921)
• 4It is worth noting here that Hennix sees her use of the empty set as being a central defining point of her Epistemic Art, which is her version of Flynt's Concept Art. Hennix understands Flynt's version of Concept Art as not being mathematically precise, in that the works must always contain at least one object that undermines the structure of mathematics. Hennix, on the other hand, starts with the empty set, which is the only given set in mathematics from which one can generate other sets, including sets with infinite objects. It is the only type of set that is not defined by its members but by what are not its members. It is the complement of the universe—everything that does not belong to the empty set belongs to the universe—and also the empty set belongs to the universe. See Flynt's conversation with Hennix in “Philosophy of Concept Art: A Conversation with Henry Flynt”and “Mysterium Fascinans: The Epistemic Art of Catherine Christer Hennix by Ulf Linde with Catherine Christer Hennix” in Other Matters for further conversations on these topics.
• 5Events surrounding this exhibition been recounted by Flynt in an unpublished manuscript.
• 6Though, according to Hennix, the four-color undecidable equation was laid out incorrectly by Avery's assistants.

While living upstate, Hennix met the poet Charles Stein, who was then becoming increasingly interested in learning about modern mathematics and philosophy. Along with the poets Donald Byrd and George Quasha, Stein invited Hennix to lead a series of informal seminars, which they called the Rhinebeck Institute. The seminars focused on Hennix’s work while also involving the study of “mathematics and logic-poetic and other artistic practices, various facets of contemporary philosophy, pre-Socratic thought and the Greek mysteries, visionary poetics and experience, oriental, psychedelic, and other forms of contemplative explorations.”1  In 1985, she published “Poetry as Philosophy, Poetry as Notation” in Wch Way, a journal edited by Byrd, Jed Rasula, and Jerome Rothenberg. Hennix framed this piece as a general introduction to her long-form, cut-up composition, The Yellow Book, which she would begin working on the following year.

Much of the poetry that Hennix produced during this period was collected in a preprint series—several small mimeographed notebooks—and circulated among friends. Only Flowers of the Black Chrysanthemum (1982/83) was officially editioned.2  The preprints were sent to Henry Flynt, Dick Higgins, and other prospective readers, but nothing materialized, and these poems have remained unpublished until now. Most of the works presented in this anthology, such as Fragments on Presocratic Four-Color Vision (1979) and Sanskrit Algebras Part I (1980), remain faithful to the original series; however, Flowers of the Black Chrysanthemum and Degrees of Unsolvability (1976—79) were edited extensively by Hennix in 2017 and 2018, specifically for this book. While much of the poetry included in Poësy Mattersis from the 1970s and ’80s, we have also included a major work that Hennix began in the late 1990s and revised in 2017 entitled No-One’s Memorial / Das Niemandsmal /, as well as some of her more recent poetry written in Sanskrit and Arabic, including Dedication for the Electric Harpsichord (2010) and selections from Ṭarīqah Nūr-Samad (2013–16).

While living upstate, Hennix met the guitarist, tenor saxophonist, and pianist Arthur Rhames, who inspired her to start playing drums again. Hennix would play with Rhames off and on until his untimely death in 1989 at the age of thirty-two from AIDS-related causes. Hennix and Rhames never formally recorded together, but one recording from a live performance on Columbia University’s WKCR exists in the station’s archive. On the recording, the artists perform a couple of Rhames’s compositions, as well as some John Coltrane pieces and other jazz standards, with the bassist Marc Johnson. Hennix, as a drummer, also played with Johnson in Henry Flynt’s Dharma Warriors, a group that would also record occasionally with the cellist Arthur Russell. Other collaborations with Flynt during this time include C Tune and Purified by the Fire—on which Hennix provides tambura backing tracks—and the recording of Stereo Piano,3  the tape presented at the Kitchen in 1979. Although the public presentations of Hennix’s music in the late 1970s and ’80s were led by Flynt, it is important to note that Flynt, too, was not well known at the time. His own work as a musician would not be widely received, at least outside of New York, until the early 2000s when his recordings from the previous four decades were released on labels including Locust Music, Recorded, and Bo’Weavil Recordings. Also during that period, Flynt’s work became the subject of a series of papers and points of reference in a number of important books on avant-garde music and art, including Branden W. Joseph’s Beyond the Dream Syndicate: Tony Conrad and the Arts After Cage (MIT Press, 2008), Benjamin Piekut’s Experimentalism Otherwise: The New York Avant-Garde and Its Limits (University of California Press, 2011), and David Grubbs’s Records Ruin the Landscape: John Cage, the Sixties, and Sound Recording(Duke University Press, 2014). In most of these texts, however, there is little or no mention of Hennix, even though she was a key collaborator of Flynt’s. (It should be noted that Flynt is not the main focus in any of these books; a full study of his work is yet to be written.)

At the end of the 1980s, Hennix left the United States and returned to Europe, first to Sweden for legal reasons, and then, in 1990, to Amsterdam for a conference with Flynt called Art Meets Science and Spirituality. She then went back to Sweden and, in 1991, to Amsterdam to work on the Museum Fodor exhibition “Parler Femme.” Hennix became increasingly interested in Lacanian psychoanalysis during this time4  and started to frame her practice within its terms, ultimately creating a new body of paintings that drew explicitly on this material for the show. In this exhibition, Hennix recast her Algebraic Aesthetics, a set of four-color and black-and-white algebraic semigroups, flanked by two red and blue homotopies side panels—one of which included a recreation of Lacan’s famous schema formalizing sexual difference.

Hennix met the photographer Lena Tuzzolino at this time. Tuzzolino’s work was also included in the exhibition, and Hennix moved in with her in Amsterdam; they lived together for twenty years, during which time Hennix embarked on a series of performances and installations based on each of Jacques Lacan’s seminars.5  A corresponding text, Hennix’s La Séminaire, is included in Other Matters.

Throughout the 1990s and early 2000s, Hennix would show parts of this body of work— alongside and in collaboration with Tuzzolino, Flynt, and Young— in a series of small group shows at Galerie J & J Donguy in Paris, Emily Harvey Gallery in New York and Venice, Museum of Modern Art Belgrade, and a number of other small spaces. During this time, she also pursued her studies of Lacan’s thought, played drums in small informal groups in Amsterdam, continued to write new Nō dramas, and extended her research in mathematics, eventually becoming a Research Associate at the Institute for Logic, Language, and Computation in Amsterdam. In 2000, Hennix received the Centenary Prize Fellow award from the Clay Mathematics Institute for her work with Yessenin-Volpin, which allowed her to travel back and forth to the United States.

In 2003, Hennix returned to making computer-generated music, creating Soliton(e) Star—a sine-wave composition modeled on the soliton wave form—and, in 2005, after a long hiatus from leading ensembles, Hennix began playing with the trombonists Hilary Jeffery and Jim Fulkerson and, soon thereafter, the Chora(s)san Time-Court Mirage. This ensemble has also included Amelia Cuni, Amir El-Saffar, Elena Kakaliagou, Amirtha Kidambi, Imam Ahmet Muhsin Tuzer, Marcus Pal, Michael Northam, Paul Schwingenschlogl, Robin Hayward, and Stefan Tiedje. The group has toured Europe, performed in New York and Hong Kong, and released a number of recordings. Hennix’s relative obscurity over the years has been, in many ways, a product of her own making—since the beginning of her career, she has rejected presenting her work as a commercial product. Instead, she has opted to circulate it primarily among friends and has not seriously considered publishing the majority of her writing. Flynt, for his part, has dedicated a tremendous amount of energy and thought to unpacking her work as a musician, poet, artist, and thinker, working, too, as Hennix’s occasional editor and respondent.

Beyond Flynt’s commentary—which has, until now, existed primarily in the form of unpublished writings and a series of seminars and lectures, often presented to small audiences at Young and Zazeela’s light and sound installation the Dream House, 1969/1993—there have been few outlets over the years for Hennix’s thought to reach wider audiences. It was Flynt who connected me with Hennix over email in 2012—I was interested in inviting her to perform in the US—and he has since actively encouraged the publication of her papers. In 2013 and 2014 I organized two shows with Hennix. The first was a new, temporary Illuminatory Sound Environment installation in Brooklyn (co-curated with Bill Kouligas), where Hennix’s piece Rag Infinity/Rag Cosmosis (2013) played in succession with two pieces by Flynt, Glissando No. 1(1979) and Celestial Power (1979). While the installation was up, there was a live performance in the sound environment with Hennix (voice and electronics), Virginia Tate (voice), and Louise Landes Levi (sarangi). The following year, I invited Hennix back with her ensemble for a ten-day residency, which resulted in Chora(s)san Time-Court Mirage—featuring Imam Ahmet Muhsin Tuzer, Hennix, Amirtha Kidambi, Amir Elsaffan, Paul Schwingenschlogl, Hilary Jeffery, Elena Kakaliagou, Robin Hayward, Stefan Tiedje, and Marcus Pal—premiering Hennix’s new work, Blues Alif Lam Mim in the mode of Rag Infinity/Rag Cosmosis (1434 A.H.).

• 1Charles Stein, “Introduction,” Being = Space  Action: Searches for Freedom of Mind through Mathematics, Art, and Mysticism (Berkeley: North Atlantic Books, 1989), 2.
• 2Flowers of the Black Chrysanthemum was written between 1982 and 1983 and published in 1990 as a small letterpress artist's book in an edition of ten. Emily Harvey Gallery hosted a reading and performance on Sunday, March 18th, 1990, with Hennix reading from both Flowers and Degrees of Unsolvability and with music composed and performed by bassist Marc Johnson and "voices" by Galen AumOller, Libby Flynt (Henry’s niece), Virginia Tate, and Hennix. Hennix also made a fragrance for the performance with Madini perfume oils.
• 3Hennix and Flynt had planned to work on a piece together with live tambura and violin that never materialized. Hennix provided Flynt with the tapes, which he ended up using for C Tune and Purified by the Fire, later released in 2002 and 2005, respectively. For “Stereo Piano,” Hennix performs on the piano, and Flynt provided the scale and other instruction for the compositions, including a request that Hennix apply her “billowing cloud” treatment to the piano. The recording was most likely made in Chinatown, Manhattan, in 1978 and recorded on Yoshi Wada's Revox.
• 4While Hennix had an expressed interest in the work of Lacan for some time, she was unable to satisfactorily read his work due to her poor French. While in Sweden, she was able to study French more and begin a serious study of Lacan’s thought through several informal meetings with the French psychoanalyst Françoise Rouques.
• 5While Hennix and Tuzzolino intended this as an ongoing project, things never really got off the ground. The talk that is published here as La Séminaire (1992) was originally given as a talk at Museum Fodor and then published (with a number of mistakes) in the catalog for the exhibition "Beyond Logos" at the Museum of Modern Art Belgrade 1992).

Poësy Matters and Other Matters has slowly taken shape over the last five years as I’ve organized, with Hennix, a number of other projects and exhibitions, including, in 2018, “Catherine Christer Hennix: Traversée du Fantasme” at Stedelijk Museum, Amsterdam (co-curated with Karen Archey) and “Thresholds of Perception” at Empty Gallery, Hong Kong (co-curated with Alexander Lau). We have also produced a series of archival releases, published with Empty Gallery. The first of these, Selected Early Keyboard Works, came out in September 2018, with more to follow, including Selections from 100 Model Subjects of Hegikan Roku by Hennix’s ensemble the Deontic Miracle, released in Spring of 2019. It is my hope that all of these activities—including this publication—will lead to a greater understanding of Hennix’s immense body of work and generate more scholarly interest and opportunities to present and experience it.

I would like to thank Henry Flynt, Hilary Jeffery, Marcus Pal, Spencer Gerhardt, Bill Dietz, and Marcus Boon for their ongoing support of Hennix’s work and their crucial insights and feedback on this project.