Forbes Prize Lecture 2016

The Forbes prize lecture for 2016 was presented during the IIC Los Angeles congress by Carol Mancusi-Ungaro.

Carol Mancusi-Ungaro serves as the Melva Bucksbaum Associate Director for Conservation and Research at the Whitney Museum of American Art, New York, and for over a decade as Director of the Center for the Technical Study of Modern Art at the Harvard Art Museums, Cambridge, Mass., which she founded. For 19 years she served as Chief Conservator of The Menil Collection in Houston, Texas. During that time she consulted on the conservation of twentieth-century paintings at the National Gallery of Art, Washington D.C., and founded the Artists’ Documentation Program wherein she interviews artists about the technical nature of their art ( She has lectured widely on the conservation of modern art, and has contributed to monographs on Jay DeFeo, Jasper Johns, Brice Marden, Jackson Pollock, Mark Rothko and Cy Twombly, and to the catalogue raisonné of Barnett Newman. In 2004 she received the College Art Association/Heritage Preservation Award for Distinction in Scholarship and Conservation, and in 2009 she was elected a fellow of the American Academy of Arts and Sciences, marking the Academy’s first recognition of art conservation. In the fall of 2016 she was awarded the Forbes Prize by IIC, and she presented this lecture in Los Angeles during the IIC congress Saving the Now: the Conservation of Modern Art. She continues to engage in research documenting the materials and techniques of living artists as well as other issues pertaining to the conservation of modern art. 

Carol Mancusi-Ungaro

I interviewed the American artist Sol LeWitt, whom I did not know, at his invitation two years before he died. He didn’t want to be documented on film. So, the interview that occurred in two sessions in 2005 was sound recorded only. He asked that the conversation be transcribed so that he could clarify the wording, and he also offered to answer questions that I would jot in the margins. It was an unfamiliar format for me. Still, I instantly appreciated what an extraordinary opportunity this was to consider carefully the concerns and reflections of a highly intelligent and informed artist. What I didn’t know at the time was that the interview, and more specifically Sol’s written replies to my questions, would hold me in their grip for the ensuing 11 years, and that my attempts to come to terms with them would mark my own evolution as a conservator of modern and contemporary art.

LeWitt was a conceptual artist, and by definition the designation signaled that the immaterial concept of his work was tantamount to its materiality (Fig. 1). Such a notion placed his work in a category of art whose dictates definitively shape our approach to its care. Instead of preserving the aged original, we are given license by means of the artists’ precise instructions to remake it in order to preserve the concept beyond the degradation of each physical iteration. Even though this directive counters our timeworn charge to preserve the materials that artists employ, the undeniable precepts of ‘conceptual artists’ definitely release us from those traditional constraints – boundaries, for example, that we would respect in treating a sculpture by Pablo Picasso or Barnett Newman. In truth, as my practice has evolved over the years, I have begun to see those traditional precepts concerning the primacy of the original physical object falter and even dissolve for non-conceptual material-based artists as well. Given this trend, I find myself grappling with the core relationship between immateriality and materiality in the work of all artists – not just conceptual artists ‒ and accordingly with the nature of our engagement in the preservation of both.

That transition in my thinking is what I would like to explore in this lecture. My focus is on the work of modern and contemporary artists who are often but not always using the industrial processes and products of our time, which were not readily available in past eras, and which are untested. As such, these artists can be distant from the making of the materials they employ, compared to their predecessors who benefited from a traditional guild system, or the expertise of professional colormen.

My comments will not apply to the work of artists like Filippino Lippi, Johannes Vermeer, or Mark Rothko whose manual virtuosity continue to overwhelm our senses by the sheer rigor of its physical prowess. When I stand in front of the art of such artists, I do not think of it as exemplary of non-conceptual Italian Renaissance, "Golden Age", or mid-20th-century American abstract painting. Rather, I experience it as the expression of gifted artists manipulating material for a specific visual effect. Although distinctly different from contemporary art in all the ways that we can identify, it is still a highly personal engagement that eschews broad historical classification in favor of an insistent interplay of idea and realization. That same engagement holds true for the art of our time.

In response to a question about the aging of his art, LeWitt wrote, ‘When they cleaned the Sistine Ceiling, they found the colors were rich and clean – not the brownish varnish color we’ve seen before. The work should look the same as the time it was made. The artist is not responsible for the falsification of time’. I was stunned by LeWitt’s phrasing that deliberately separated the painstaking artist’s investment from the ‘falsification’ brought about by time. Although I understood his concern over the potential distortion of aged material, I had never thought of it as a falsification, as such, and I was not immediately ready to convert to his thinking. After all, I had already spent over three decades of my professional career dedicated to saving for posterity every small bit of original flaking paint, every nuance of aged media in each work of art, and every scrap of material ever touched by an artist. Therefore, it was not without reservation that I tried to digest the words of this profoundly articulate and insightful conceptual artist who chose to speak to a conservator, of all people, in the waning years of his life.

Thoughts about our cultural acceptance of unpainted Greek sculptures that were once colored came to mind. I wondered how Praxiteles might have responded in an interview to a question concerning the current appearance of his surviving marble work or its Roman copies. Pliny tells us that when asked to name which of his sculptures he valued most highly, Praxiteles responded ‘those to which Nicias [a famous Greek painter] has put his hand’. Today Praxiteles’ art does not ‘look the same as the time it was made’ to use LeWitt’s words. Clearly, the Greek artist’s preference for color has been lost to time, and we have culturally accepted that ‘falsification’.

Of course, coming to terms with time is a driving force of our profession. Conservators customarily make decisions regarding the effect of time on the physicality of a work of art we’re restoring or a substance we’re using in a treatment. It is easy to categorize Sol’s remark as that of an acknowledged conceptual artist and confidently repaint or remake his work because he himself explained that his ‘ideas about art are not much involved with material as an end, but merely as an agent for making an art-idea and an artwork’. Rather they value a distinction between concept and perceptual manifestation. But what about artists who are not categorized as ‘conceptual artists’ and are notoriously invested in the material aspects of their work but who to an increasing degree share in LeWitt’s attitude. I’m thinking of the American artist, Richard Serra.

I have never met nor interviewed Richard Serra, but I was struck by his responses in an interview published in the Art Newspaper in 2013. Apparently, a drawing owned by him and included in an exhibition of his art at the Metropolitan Museum of Art, New York, was abraded and Serra reworked it. He regarded the intervention as a conservation treatment, and when asked by a concerned museum professional if the work should be double-dated, he said no ‘because the concept has not been reworked’. He explained, ‘… let me put it this way: usually … if a work is destroyed or damaged and there is the possibility of recovering it, then if it can be saved, I try to save it … I think it is my responsibility to make sure the work exists in the way I want it to exist’ (Gilbert, 2013). In this published statement, we hear the same thoughts expressed by LeWitt regarding accountability and authority, except that this time they are from an artist celebrated for his investment in materiality. Yet he claims a responsibility to preserve the work as he wants it to be seen and he insists upon the primacy of the date of the concept. Serra took the same uncompromised position with regard to the double dating of Prop, a 1968 work owned by the Whitney Museum that he partially remade for an exhibition at the Museum of Modern Art (MoMA), New York, several years ago. At the time, as a conservator, I vehemently objected to the absence of a double date (that is, an institutional notation of an original date of the making and the date of additional working by the artist separated by a slash). Maybe double dating seems logical to conservators because we prize the sanctity of the original fabric of a work of art and want to distinguish it from subsequent interventions. However, given the priority of the artistic investment at the moment of conception for both an avowed ‘conceptual artist’(LeWitt) and a blatantly ‘non-conceptual artist’ (Serra), I now find the proposition of double dating more complex and nuanced. It seems fiercely dependent upon the nature and extent of the artist’s re-entry. Justifiably, if an artist goes back into a work and significantly changes its concept or form years later, then double dating with a slash seems reasonable. Is there a conundrum at work here with regard to an artist’s innate relationship to the work and its preservation that may fundamentally impact our treatment decisions and actions in addition to our official notations?

With that question in mind I recall two conversations I had with Cy Twombly in the late 1990s. Standing together in front of his opus Say Goodbye, Catullus to the Shores of Asia Minor 1994, Cy asked me what could be done to mitigate a distinct difference in ground color in one section of the large painting (Fig.2). I asked how it had occurred and he explained that he had created the painting in spurts over two decades. He rolled out just enough of the prepared linen that he intended to use during a painting campaign and kept the rest unfurled on its proprietary wooden dowel. During a hiatus of several years, the unrolled fabric aged differently from the exposed and painted canvas. This difference in aging is a phenomenon familiar to us but an unexpected development for Twombly. When I explained there was nothing I could do to correct the difference, he let it go, but I was struck by how engaged he still was with a painting that he had begun over 20 years earlier.

On another occasion, while discussing one of his Lexington paintings (Untitled 1959), he regretted a linear score in the paint that resulted from his folding the canvas during a shipment from the US to Italy in the late 1950s. Upon its arrival in Europe, his wife inpainted the fold line, but Cy was never satisfied with the result despite our subsequent attempts to improve it at The Menil Collection, Houston, Texas. Once during a walk-through of the Twombly Gallery, he nonchalantly confided to me that he intended to add more elements to the painting when he had a chance, in order to visually break up the linear distraction. He died before that opportunity arose. Yet, the assumption that he still had the authority to do that even though he no longer owned the painting both impressed and plagued me as a museum professional. There existed, despite the passage of time, an insistent commitment and ‘responsibility’ to the work that Twombly felt entitled him to re-enter it.

This ‘insistent engagement’ is not a new phenomenon born of the late 20th century. To cite just one example, Pierre Bonnard was notorious for asking friends to distract guards while he retouched a painting on exhibition and for visiting collectors with a small paint box in his pocket (Whitfield 1998: 26). In these instances, the visible changes did not affect the conceptual construct. Yet, the artists still harbored an obligation akin to Serra’s to get it the way they wanted it, despite the inconvenience of ownership by a museum or private collector. I began to see that an artist rarely if ever relinquishes the intellectual ownership of her work.

Recently, Michael Heizer’s Actual Size: Munich Rotary 1970 was installed at the Whitney Museum for the first time since its acquisition in 1996 (Fig. 3). The work of art consists of six projectors, developed specifically for it in 1970, six stands, and six glass slides of film-based positive images. He made the images with a handheld camera while standing in a physical depression that he created in the alpine gravel of Munich, Germany. Each glass slide is a composite of film fragments cut and assembled by the artist. Although shown three times before its iteration at the Whitney, Heizer was never satisfied with the previous installations. I use the word ‘iteration’ because Michael in concert with us remade the slides from digitized images of the original analog film and then tailored their dimension to fit the museum’s exhibition space. Despite these modifications to the slides, he insisted that the projectors not be changed in any way, except for minor updates to meet current directives on electrical safety. It never occurred to Heizer that the institution might not condone his intervention. To his mind, the aged original images no longer conveyed the intentional contrast between the sharp punctuation of the gravel and a subtle confluence of the edge of the depression with the horizon. He had to get it the way that he wanted it to exist. Formerly dissatisfied, Heizer now authorized this iteration as the official version. As conservators, we struggled with the nature of our multi-year intervention, in this case recognizing that we had co-finished the work with the artist. Heizer wanted to see the work realized as he had conceived it before he died. He felt he owned it and in truth he did own the immateriality of it. However, the Whitney Museum owned the material manifestation. The carefully reworked result was true in the artist’s estimation, but how would one describe the conservators’ engagement?

In response, I am reminded of an interview I conducted under the auspices of the Artists’ Documentation Program with Richard Tuttle in 2006. Having worked with several conservators over the years, the artist respected our profession and in the course of our conversation conveyed an impressive grasp of our abiding principles. During a break in the filming, Richard dismissively predicted, with regard to the aging of his art, that over time it would all have to be remade. I swiftly responded in jest, ‘Oh, then I’ll be out of a job’, to which he replied, in characteristic seriousness, ‘No, you’ll be making it.’ At the time, I laughed, but since then I have increasingly seen his prediction come to pass. While suited to Richard’s work, this course of action naturally does not apply to all art, but it is not restricted to his production either. Whether in the guise of making exhibition copies, replacing damaged or inherently fragile parts, or upgrading technology, replication has joined our repertoire of treatment alternatives. That does not mean that it never existed before as an option, but today the authority and frequency with which it has entered our conservation studios beg for its characterization within our professional modus operandi.

To begin with, how would we distinguish a replica from a mere duplication?
Robert Smithson made a clear distinction with regard to one of his works entitled Mirror and Crushed Shells (Sanibel Island) (Fig. 4). In a letter Smithson wrote the following to Andy Warhol:

Dear Andy,
This is to certify that the Mirror with Crushed Shells (Sanibel Island) is an original work of art. It consists of 3 mirrors which may be restored if broken, and one burlap bag of crushed shells collected by the artist at Sanibel Island, April 1969. If any shells are ever lost, the owner has the right to restore the work by collecting more shells from Sanibel Island (northern part of island – see map of site which is part of the work). The 3 mirrors are held in place in a corner by the pressure of the shells only (see photo). The work is owned by Andy Warhol, and cannot be duplicated.
[Signed] Robert Smithson

For many years in citing this example, I have been intrigued by the demarcation that Smithson has made between replacing all the parts of the work and duplicating it. In the current context of museum practice, I see a different irony. Smithson categorically rejected the making of duplicates in this work. Yet, museums worldwide have installed exhibition copies of Smithson’s art – of his rocks, for example – rather than assume the cost of packing and shipping heavy boulders across oceans. There is rarely any indication that the exhibited material is not original since it seems the concept overrides the initial materiality in certain museum applications. Still, exhibition copies are duplicates that are destroyed after use or otherwise isolated, and artists are protected by copyright laws from unauthorized duplications. Such a replication, in an institutional sense anyway, is an intensely researched, vetted, and approved reiteration, for it is often the artist and conservator among other museum professionals who inform that process.

Years ago an exhibition of early work by Ed Kienholz was installed at the Menil Collection. Among the prominent works on display was a pair of related sculptures entitled John Doe 1959 and Jane Doe 1960, names often used as allusions to the average American male and female (Fig. 5). John Doe represented the archetypical man equipped with wheels that assured his mobility, a symbolic cross in his empty heart, and a portable male part that could be taken out of the drawer and used as the spirit moved him. Jane Doe, on the other hand, embodied the demure young woman who was stationary, wore a white bridal gown, and hid beneath her dress three drawers containing elements associated with the three stages of womanhood: virginity, childbearing, and old age.

When John Doe entered the Menil Collection, the portable male part made of cheap industrial rubber had completely disintegrated into powder and Kienholz remade the part from a new rubber mask reminiscent of the original one he had purchased in Los Angeles decades before. Months later when Jane Doe arrived as a loan for the exhibition, the curator was stunned by the tawdry and aged appearance of her wedding gown (Fig. 6). Unlike the inviolate whiteness of the original, the fabric was now irreparably stained by the owner’s assortment of pet birds. Unfortunately, the artist had since died, but his widow and the curator (who was a confidant of Kienholz’s) authorized the making of another dress because the irreparably aged condition of the original destroyed the artist’s conceptual framework. Were I to cast this example in LeWitt’s terms I would avow that the immateriality of the work was falsified by its damaged materiality. So, I made another dress and basically effected Tuttle’s prediction.

In other words, I was a co-producer of Ed Kienholz’s work. I have used the word ‘co-producer’ for lack of a better term to describe the relationship of the conservator to the artist when remaking or significantly engaging in the materiality of an artist’s work. The term is not meant to suggest equality or creative collaboration with the artist.

More and more, I am hearing conservators in institutions muse that we, supposed preservers of the past, are becoming co-producers alongside emerging and sometimes canonical artists. We help the artist figure out how something should be made or we research thoroughly how something could be perfectly replicated. Then we do it, but aren’t we conservators dedicated to the preservation of the original materialization of a work of art, not the making of it? Has something changed with regard to our professional manner of working?

It seems with old master art anyway, we’re perfectly comfortable preserving what we determine to be the inevitable appearance of age. For instance, we respect the craquelure in Rembrandt’s paintings and the distressed wood in Donatello’s Magdalene. We preserve these aged surfaces and even venerate them, because they embrace the reassuring passage of time, and the effect is beautiful. Still, however cogent that assessment may seem (and I’m a proponent), it’s a bold judgment. The treatment is based on a professional assumption of how an aged work of art should look, and that premise may in fact not reflect the artist’s initial artistic investment. Yet, we often pride ourselves on getting into the artist’s skin in order to identify aberrant interventions and thereby restore the work to its ‘original’ state ‒ allowing of course for some degree of aging, which we have determined is unavoidable, and therefore acceptable.

This is commendable work, and we do it because at heart, especially in a museum context, conservators are keepers of history. However, in truth, we do not restore works of art to an original state, despite our contentions and nomenclature. We may remove past restorations and other human interferences, but we do not end up with a work in its first youth. Rather, it is a naturally aged state of the work of art, not as it appeared when the artist put down his or her brush or chisel or final screen, and assigned a signature. We cannot really bring a Pollaiuolo or da Vinci painting back to what we believe was its primary appearance, and therefore we temper what has survived in order to come as close as we can to the original expression. Garnering whatever information we can glean from the artist or historical chronicles of practice, we utilize our professional intuition, expertise, and skill to restore the work in the artist’s manner. As such, are we not in essence co-producers? Even though the nature of our engagement may differ in degree, the overriding directive of working closely with a living artist or deceased artist’s legacy to simulate what was originally achieved remains eerily similar.

I certainly recall the controversy that was caused by the stripping of all paint that was not original from trecentro and quattrocentro paintings in the Jarves Collection at the Yale University Art Gallery, New Haven, Connecticut. Following the directive of the curator, the conservator left us with fragments of former artworks that were subsequently reconstructed by talented conservators elsewhere. We saw paintings transition from aged remnants to fully restored works and that informed transition or to a degree, ‘co-production,’ rings true to what is occurring today in my mind with the art of our time.

Another complication for us embedded in the diverse categories of contemporary art is the thorny question of precisely what is the original to be preserved. A case in point, representative of a growing class of objects, is a work by the artist Josh Kline entitled Cost of Living (Aleyda) (Fig. 7). Acquired by the Whitney Museum two years ago, it is a non-traditional portrait of Aleyda, a hotel housekeeper in New York, whose humanity has been reduced to an impersonal fragmentation of her body parts that are barely distinguishable from the tools she uses; the socio-political overtones are strong. The sculptural assemblage consists of a commercially made janitor’s cart equipped with LED lights that bears sculptural body parts and other forms that were 3-D printed in plaster and ink. A code or programming language dictated how the computerized machine tools should make the forms in order to accomplish its task. Acknowledging that the code for the 3-D printing of parts held detailed information beyond the current capability of 3-D printers, the artist advised that we discard after use the current physical manifestations of the prints, i.e. the brushes, sponges, bottle, Aleyda’s head, hand, and foot and plan to reprint them at a later date when the capability of the printers will have evolved to match the detailed sophistication of the code. When pressed, Kline was vague as to the value of the current printed parts i.e. whether we should retain them in the historical record or not. He wasn’t exactly sure when they should be reprinted, nor what to do about old file formats of data as the software changed over time. However, even though the code was the sustainable component of the work and the prints were not, Kline was adamant that the objects were his art and that he was a sculptor. But if the physical reality of the work of art continues to change intentionally over time, then what is the date of the original? Maybe it is the date of conception and not that of the current materialization after all? And to take that notion further what are we, as conservators, charged to conserve?

A look at IIC’s articles of association is instructive in that it confirms that our founding fathers focused their attention in the 1950s on materiality but kept an impressively open mind with regard to interpretation. Although they stipulated that ‘Conservation means any action taken to determine the nature or properties of materials used in any kinds of cultural holdings or in their housing, handling or treatment,’ they went on to authorize us ‘to take any action necessary to further the understanding and controlling of the causes of deterioration of Historic and Artistic Works’. Since causes of deterioration can be broadly interpreted within our current scenario, I began to reconsider our working assumptions as a profession. Do we presume that there is a totemic state of an aged work of art? I’ve often heard myself naively propose that the endgame with regard to aging is the moment that the work of art enters a museum’s collection. Is that one of our assumptions, or are conservators participants in an exchange with multiple conditions that arise over time? As conservators, we seem to be customarily attuned to the original concept and the moment of realization. Even though we admit that physical states are always changing, we routinely accept the charge to try with increasingly sophisticated means to mollify those transitions. It gets particularly complicated if we try to stop aging by turning the clock back to say Praxiteles’ colored sculptures because art (and art appreciation to a degree) is a flow of cultural creativity. It’s ongoing, and conservators are stewards of this process that is alive and changing.

Recognizing the duality of art as both form and expression, Richard Tuttle clarified that even though art is invisible, it is indelibly linked to the visible. He noted that conservation is about the visible side of the link but not only about the visible. For this reason, he concluded, ‘my generation’s kind of art has been hard on conservation because it pushes conservation on that one side where art becomes visible.’ Traditionally, conservators have assumed decisive authority over the physical state of the visible by determining the feasibility of treatment options. Naturally, informed art professionals and the marketplace have exerted particular influences but ultimately conservators have been the notoriously reluctant but decidedly determinant players. Even though artists’ opinions have been sought routinely, the decision-making has resided within the institution. Interestingly, just as conservators are becoming more comfortable with realizing the artist’s vision through co-production, the artists are assuming more authority over the aging state of their material expression and are increasingly seeking conservators’ input.

Eight years ago, the Whitney Museum sensed what was developing with regard to authority and tried to come to terms with the incrementally changing cultural terrain by forming a Replication Committee. The purpose of the committee was to debate and decide upon the appropriateness, for lack of a better word, of each request for partial or full replication. The committee consists of stakeholders equally representing departments that range from curatorial and conservation to collection documentation and legal counsel. At stake was authority over the state of the materiality of the work of art. We worked closely with the artists whose work was under discussion and their sense of the immaterial guided our interpretations. It ended up being a balancing act between the artist’s authority and the institution’s role as a keeper of history. We naively thought that over time we would arrive at consistent decisions pertaining to kindred cases and thereby set precedents upon which policies could develop. To the contrary, as the diversity and breadth of the caseload has expanded, we are increasingly confronted by inconstant decisions that reflect and ultimately connote evolving paradigms.

So where do conservators stand in this shifting cultural landscape? Perhaps our traditional devotion to preserving the aged appearance or initial iteration of a work of art at all costs when it can reasonably be remade needlessly falsifies the artist’s artistic investment. Since we are charged with the preservation of not only the physical but also the inseparable conceptual aspect of art, I wonder if indeed we are the arbiters of ethics in this scenario. Undeniably we are the professionals in the art trenches who are actually doing the work and not solely writing or speaking about it. We might be caught in a contemporary fluctuation of values and approaches, but we have a sustainable tradition to draw upon. Throughout the ages there have been multiples, replicas, and certainly fabrications by hands other than the artists such as sculptural editions. Some have survived and some have come down to us in the form of acceptable, albeit ‘falsified’, (that is, not true to the artist’s original artistic investment) copies. In defining a way forward, we as a profession have rigorously taken into account the historical legacy or the active voice of the artist. Moreover, our timeworn methodologies have relentlessly tried to recognize and respect the authority of the artist’s voice. By studying related works or researching contemporary texts for technical clues, we partner with the artist’s awareness before embarking on a treatment. We are continuing to do that in the contemporary scene by co-producing, emulating, and rigorously documenting actions in order to confront potential falsifications of time. As highly trained and informed contributors to an ongoing professional dialogue, foreseen by our forebears, we exercise a privilege that is not only ambitious but exhilarating.

Addressing what would become the preferred format of his posthumous catalogue raisonné, Sol LeWitt shared the following thought with me after our last session:

I hope you’re going to write this up. It could be really, really, very important to the book because it’ll bring everything together, materially and ideologically … you take not only the material problems, technical problems, but also problems of thinking about how the work is made. So that’s the whole thing, in some measure. I’m glad you’re doing it.

Initially challenged by Sol’s remarks, in the end I decided that he got it right. Time can falsify the initial sensation of the work of art which may not come down through the ages as intended, and the responsibility does not rest with the artist. Rather it is the shifting taste of time that reinterprets the appearance of the work of art and may even remake it to a degree. It is a fluid process. So, while the artist responsibly insists that the work exists the way he or she wants it, in reality that edict prevails only in the artist’s lifetime. Shortly thereafter, the work belongs to another time and rests in the hands of those responsible for its care, conservators among them. LeWitt recognized this inevitability and intentionally prevented that falsification by authorizing with precise instructions his work to be remade into the future. Yet, like Tuttle, he also intuited that preservation and now replication would reside in the conservator’s domain, given our professional propensity to look at art both materially and ideologically. So, it seems fitting to end these thoughts by acknowledging with fervor the evolving complexity these days of our professional pursuit while also taking note of the ambitious and often ill-defined endeavor, in LeWitt’s terms, of ‘doing it’ because after all ‘that’s the whole thing, in some measure’.

1. Sol LeWitt, written addendum 25 July 2005 to transcript of interview with the author on 22 February 2005.
2. Pliny the Elder, 77‒79CE, Naturalis Historia (Natural History), book 35, chapter 2. This is an unrivaled compendium of Roman knowledge.
3. Sol LeWitt, written addendum 25 July 2005 to transcript of interview with the author on 22 February 2005.
4. Richard Tuttle, personal conversation 30 January 2006 with the author during a break in the filming of an interview with him. The interview is preserved with Artists Documentation Program oral history interviews and records, Menil Archives, The Menil Collection, Houston, Texas, and is available with others at The Tuttle interview is preserved as a sound recording, and a transcription is available on the website. There is no record of the comment I cited other than my memory of the personal conservation between us during the break in filming.
5. Robert Smithson to Andy Warhol 9 July 1969, preserved in the object files for the artwork, The Menil Collection, Houston, Texas.
6. Memorandum of Association of the International Institute for Conservation of Historic and Artistic Works, 21 March 1950. See
7. Richard Tuttle 30 January 2006, in Artists Documentation Program oral history interviews and records. Menil Archives. The Menil Collection, Houston.
8. Sol LeWitt, 17 March 2005, transcript of interview with the author on 22 February 2005.

Gilbert, L. 2013. ‘Serra’s “threat” to Broad Collection,’ The Art Newspaper, 242: 4.
Whitfield, S. 1998. Fragments of an Identical World, New York: Museum of Modern Art.

Figure captions

Figure 1 Sol LeWitt, 4th wall: 24 lines from the center, 12 lines from the midpoint of each of the sides, 12 lines from each corner, from Wall Drawing #289, 1976, wax crayon, graphite pencil, and paint on wall, dimensions variable. Whitney Museum of American Art, New York, 78.1.4, purchased with funds from the Gilman Foundation Inc. © 2017 The LeWitt Estate/Artists Rights Society (ARS), New York. Image: Jerry L. Thompson.

Figure 2 Cy Twombly, Untitled (Say Goodbye, Catullus, to the Shores of Asia Minor), 1994, The Menil Collection, Houston, Gift of the artist. Discrepancy in ground color at center left of image. Image: Paul Hester.

Figure 3 Michael Heizer, Actual Size: Munich Rotary, 1970, six custom made aluminum projectors with steel stands and six black and white film transparencies mounted between glass, dimensions variable. Whitney Museum of American Art, New York, gift of Virginia Dwan, 96.137. Installation view for Open Plan: Michael Heizer (25 March to 10 April 2016). © Michael Heizer. Image: Ron Amstutz.

Figure 4 Robert Smithson, Mirror and Crushed Shells, 1969, private collection.

Figure 5 Edward Kienholz, John Doe, 1959, The Menil Collection, Houston, and Jane Doe, 1960, from the collection of Laura Lee Stearns.

Figure 6 Jane Doe, 1960. Left: the dress in 1995. Right: dress in original condition.

Figure 7 Josh Kline, Cost of Living (Aleyda), 2014, 3D printed sculptures in plaster, inkjet ink and cyanoacrylate, with janitor cart and LED lights, overall: 113 × 91.4 × 49.5 cm, Whitney Museum of American Art, New York, promised gift of Laura Rapp and Jay Smith, P.2014.118a o. © Josh Kline. Image: Ron Amstutz