For historians of photography, Josh Ellenbogen’s Reasoned and Unreasoned Images provides a significant theoretical discussion of photography’s aim to capture the visible and non-visible and, more widely, of its complex relation to human perception, cognition, and memory. The book undertakes close examination of the photographic oeuvres of Alphonse Bertillon (1853–1914), Sir Francis Galton (1822–1911), and Étienne-Jules Marey (1830–1904) as approached through the work of philosopher of science, physicist, and mathematician Pierre Duhem (1861–1916). Through this approach, Reasoned and Unreasoned Images becomes both a work of the philosophy of science and the history of photography. Indeed, this is its greatest strength. Less interested in particular images produced by Bertillon, Galton, and Marey than the reasons behind and justifications for their entire photographic projects, Ellenbogen analyzes the intentions, perceptions, and explanations of these photographers on the capacities of photography to do scientific work. In doing so, he questions the logic of each of their methods to exploit the tensions and contradictions within them, and thus those of photography’s status in relation to vision during the fin de siècle.

Readers should not expect a biographically driven narrative on the photographers examined in Reasoned and Unreasoned Images. Instead, the journey the reader undertakes is guided by thought-provoking questions through a series of chapters that progressively build upon the previous one to form a layered work of interwoven arguments that cannot easily be pulled apart (for instance, to function as course readings for students). Ellenbogen also makes bold claims throughout his book that it offers new “theoretical resources” and a “general intellectual framework” for analyzing the history and very nature of photography, on par with the pioneering writings of John Tagg, Allan Sekula, Lorraine Daston, and Peter Galison. Ellenbogen’s book must be slowly and thoroughly digested as a whole, making it an important but challenging work. Nor does Ellenbogen write for those who may be new to the field of the history of photography. Written by a specialist for specialists, the book expects the reader to already be familiar with Bertillon, Galton, and Marey, along with a host of other artists (Sir Joshua Reynolds), photographers (Julia Margaret Cameron, William de Wiveleslie Abney), scientists (Ernest Mach, Michel Eugène Chevreul), sociologists (Gabriel Tarde), and philosophers (Charles Sanders Peirce) who make appearances throughout the book. This is particularly apparent in Ellenbogen’s introduction, which reads more as a conclusion or summary. It is at times unclear, with somewhat vague mentionings of perceptions and practices by these photographers and philosophers (themselves not properly introduced until later) that only become comprehensible in the chapters that follow. Be patient, for what is to come in the text is worth the wait.

Ellenbogen intentionally chooses images that do not conform to and thus problematize the employment of photography to picture what we see, i.e., its indexical nature. He refers to this as a photography of the non-visible, extra-visual, or invisible (that which cannot be seen by the naked human eye), and he concentrates on Bertillon’s photographs of criminals, Galton’s composite photographs, and Marey’s serial photography or “registration events.” Amid deceptively simple questions—What makes a good or useful scientific photograph? What does a photograph offer that a hand-drawn illustration or a graph cannot?—lie extraordinarily complex issues. The contemporaneous photographs under discussion “run against the grain of certain standard accounts of what it means for a photograph to operate as a useful and legitimate agent of knowledge” (3).

The book is divided into three main parts, one for each of the three main photographers, though all three parts constantly discuss the similarities and differences between their work. The first part concentrates on the criminal archive maintained by Bertillon. Like Sekula, Ellenbogen explains Bertillon’s use of photographs as a means to supplement other records in order to create an efficient and useable archive of criminals in Paris. Preferring certain conventions over others, especially profile shots, Bertillon’s photographs were aids for specially trained policemen first and the public second. These conventions emerged out of a dissatisfaction with other means of recording used to “fix” the identity of criminals, especially repeat offenders. Ellenbogen discusses Bertillon’s explanation of the “ideal lens” through which to capture the most representative likeness of an individual, exemplified by a photograph of the figure’s face in semi-repose as the visualization of the most typical look, a “synthetic assemblage of different moments we have seen or could see in a face’s history” (37). This was apparently a statistically calculable average, based on the methods of Adolphe Quételet, known as the binomial curve.

Applicable to both the individual and group, Bertillon organized his archive around his faith in the binomial curve, a line of distribution that followed a mathematically lawful pattern, and thus categorized the archive according to the measurements of the different body parts of criminals from the most typical (the central mean) to deviations from that norm. Photographs of criminals were the last stage in identification, as Bertillon doubted their efficacy in producing the right sort of synthesized data that resembled the individual. Interestingly, by highlighting the differences Bertillon viewed among the initiated and uninitiated or lay observer, Ellenbogen complicates Bertillon’s notion of “resemblance” relative to human perception and memory, as well as what photography can and cannot do in fixing identity. Thus, Ellenbogen argues that Bertillon’s photographs produced information on criminals not “invisible” to the human eye but only perceptible to experts trained to read faces in particular ways, especially according to physiognomy, as a means to synthesize, abbreviate, and condense perceived data (chapter 1). Such data of the “characteristic” (a subject in chapter 3 related to all three photographers) were contained within the photograph as well as within the memory of the expert. This leads Ellenbogen to Duhem as a resource through which to understand Bertillon’s photography, based on concepts of data condensation, mental picture-making, memory, and perception (chapter 2).

I should mention here that there is a complex but productive conflation throughout the book between photographic images and mental images, between pictures produced by photographic technologies and those by the human mind and memory. This is inherent in the book’s title, Reasoned and Unreasoned Images, a reference to Duhem’s understanding of mental “drawings” as “creatures of reason” and to Bertillon’s description of “unreasoned images” of individuals formed in passing that fade rapidly from memory, which Ellenbogen compares and contrasts with Bertillon’s, Marey’s, and Galton’s photographs.

Continuing with the topics synthesis and the ideal, part 2 focuses on Galton’s composite photographs, which Ellenbogen argues visualize mental operations of memory and abstraction—in other words, of ideas. In Galton’s composite photographs (produced by exposing multiple, individual portraits onto one photographic plate), the face is not an actual individual but a synthesis of many, and thus is not visible in reality but a visualization of an (inherently invisible) idea(l) or “type” (“The Jew,” “The Criminal”), itself the product of lawful patterns resulting from the “beauty” of the binomial curve. While studies on Galton’s photography are plentiful, Ellenbogen explores and problematizes his photography as a way of perceiving the world, and vice versa—that the mind is “impressed” by visual data just like a sensitive photographic plate, and thus the mind operates like a camera. The composite photographs become visual representations of the binomial curve, or the visual equivalents of graphs, by providing a synthesis of data much like the mind produced cumulative “blended memories” to form ideas about objects. Again Duhem’s beliefs are used to enrich the discussion, with Ellenbogen calling on the philosopher’s differentiation of “ample” versus “abstract” minds (chapter 6). For Galton, the ghostly outlines of faces in the composite photographs were absolutely necessary as visualizations of deviations from the norm that could or could not be measured (in the latter instance making the photograph not just equivalent but superior to graphs). According to Galton, their blurry presence made for a “good,” “beautifully idealized,” and successful photograph; their absence, “monstrous” (chapter 4). A concern with focus and blur drives a discussion in chapter 5 on contemporaneous photographers’ work, such as Cameron’s, and theory, including those who used Reynolds’s writings on picturing the “ideal” to explain photography.

Part 3, on Marey, is the culmination of the book, arrived at only through lengthy discussions of Bertillon’s and Galton’s photographs and their ideas on data production. While Marey crops up repeatedly beforehand, this last part is devoted to “the disappearance of antecedents that stand before the image” (170) in his photography, at once original and artificial. As Ellenbogen explains, there is no denial or effacement of human agency in Marey’s work. It is not unmediated; indeed, it cannot be. His photographs only exist because of mediation—the “homme squelette” suit worn by his subjects, the intricate setup of multiple cameras, the conditions of the space—and, as Ellenbogen points out, Marey himself described these events as “artifices” (chapter 7). If Marey’s photographs record data that the eye can never see, what standards, the author asks, do they follow? Ellenbogen once again turns to Duhem’s work, “performing interpretative duties” (175) to analyze afresh Marey’s photography. Chapter 7 concentrates on what Marey meant when he said his devices, which sought to register above all the expenditure of energy using “the graphic method,” were “like new senses.” Marey’s devices (including his sphygmograph, which recorded the pulse, and the cameras he created for his serial and chrono-photography) produced by mechanical means and thus beyond the human senses graphic traces of movement and energy, which Marey referred to as “registration events.” Drawing on the work of Marta Braun (Picturing Time: The Work of Étienne-Jules Marey [1830–1904], Chicago: University of Chicago Press, 1992), Marey’s connections with Eadweard Muybridge, and the thought of Tarde, Ellenbogen explores concepts of sensation and inscription. He concludes that, “In Marey’s procedure, photography both manufactures data that have no place in what we see, and stands in for a part of the scientist’s own labor in providing a synthetic treatment of the data”; as such, “Photography itself becomes a force of the [scientifically] lawful” (193).

In chapter 8, Ellenbogen clarifies that for Marey photography performed scientific work, acting as a “prosthetic” for the minds of scientists. His photographs, such as Geometric Chronophotograph of the Human Walk (1886), were produced by rapid-fire cameras aimed at subjects wearing special suits marked with dots and lines; as these subjects walked, the cameras registered them in motion so as to form the sinuous lines and even “ideal curves” of graphs. The camera, as a registration device, was thus perceived by Marey to have the capacity to possess “intelligence and genius” because it translated data into graphic or schematic form, and thus already performed some of the work of synthesizing and condensing that information into general scientific laws. Ellenbogen concludes,

Too often, discussion of photography’s role as an agent of knowledge resorts to an easy binarism, placing on one side . . . the artifactual, the conventional, and the interventionist, and casting them as simple antagonists to an opposing idea of the scientifically valid. Marey’s project demonstrates the difficulties this model faces, and it poses a series of additional challenges to how we often talk about photographs. . . . Marey’s project did not aim to keep faith with originals, but instead made images that functioned as originals, doing so in ways that made the objects it generated already “schematic.” (214–15)

Ellenbogen aligns Marey’s approach with those of today’s virtual technologies, particularly those which produce images that actually enable scientific investigation rather than serve as handmaidens to visualize already generated data.

Throughout the book Ellenbogen stresses that his aim in writing Reasoned and Unreasoned Images is to provide new ways of thinking about the ability of an image not to reproduce a given, visible reality but to produce knowledge. In the case of Bertillon, Galton, and Marey, he convincingly argues that they did this quite literally, by producing new information and visual data that did not previously exist, whether to human eyes or minds. These are photographs without antecedents, Ellenbogen explains, and thus cannot be “indexical” or a trace of something that existed beforehand. For these photographers, the photograph produced knowledge in the same way the mind did, and frequently in ways superior to it. Overall, Ellenbogen’s claims to rethink the history of photography are bold and provocative, paralleling the work of Joel Snyder (“Visualization and Visibility,” in Picturing Science, Producing Art, Caroline Jones and Peter Galison, eds., London: Routledge, 1998, 379–97), Kelley Wilder (“Visualizing Radiation: The Photographs of Henri Becquerel,” in Histories of Scientific Observation, Lorraine Daston and Elizabeth Lunbeck, eds., Chicago: Chicago University Press, 2011, 349–68), Melissa Miles (The Burning Mirror: Photography in an Ambivalent Light, Melbourne: Australian Scholarly Press, 2008), and Tanya Sheehan (Doctored: The Medicine of Photography in Nineteenth-Century America, University Park: Pennsylvania State University Press, 2011) (click here for review), to name but a few, on the photography of science and medicine.