Figure 13.1. Civilization IV Map
In 1965 Tom Wolfe wondered whether media theorist Marshall McLuhan might be “the most important thinker since Newton, Darwin, Freud, Einstein, and Pavlov” (Stearn 1967, 15). George Steiner described him as “this enormously exciting iconoclast” (236). Even McLuhan’s detractors, and there were many, could grant the value of his provocative interventions: despite considerable reservations Raymond Williams described The Gutenberg Galaxy as “a wholly indispensable” book, and Jonathan Miller was willing to concede that “enough of the doors that he opens are exciting and productive to make him worth studying” (189, 236).1 At the height of his fame, or perhaps infamy, McLuhan [page 258] was declared “the oracle of the electric age” by Life magazine, appeared on the cover of Newsweek, was interviewed by Playboy, and hosted an NBC TV show entitled This is Marshall McLuhan.2 Then, following the “McLuhanacy” of the 1960s and early 1970s, and his death in 1980, McLuhan’s work and ideas dropped beneath the critical and popular radar: interest waned, books went out of print. It was not until the eve of the new millennium that “another quasi-global outpouring of interest and influence tied once again to emerging communications technologies and information systems” developed, and Gary Genosko could proclaim that “For better and for worse, a McLuhan renaissance is in full swing” (Genosko 1999, 1). A raft of new publications on McLuhan coincided with reprints and critical editions of his work,3 whilst Wired magazine verified this “second coming” (ibid.) by canonizing McLuhan as its “patron saint”.4
In this chapter I would like to examine whether any of those exciting and productive doors that McLuhan left open might lead to theoretical resources which could usefully inform the consideration of visual and environmental rhetoric. In particular, I will take up McLuhan’s notions of visual and acoustic space and consider their utility for thinking about certain aspects of a relatively new medium whose increasing importance and popularity has largely overlapped with the resurgence of interest in the work of Saint Marshall: that of digital games. I would like to investigate what McLuhan’s iconoclastic ideas can tell us if we consider at one and the same time the complicated visual nature of digital games and the implicit environmental discourses they comprise. Genosko suggests that “the McLuhan legacy was singularly devoid of progressive political ideas and remains largely the same today, with a few exceptions” (1999, 12). This chapter might be considered, I hope, one of those exceptions. My objective is to reflect on what McLuhan has to say about media as environments in order to better understand the nature of the rhetoric, specifically the environmental rhetoric, constituted by the medium of digital games. My suggestion is that digital games, as a distinct medium, work to persuade players of their immediate and continuing participation in the environment of which they are a part. By way of illustrative example, but also in order to complicate the chapter’s own message somewhat, I will examine Sid Meier’s highly successful and enduring game Civilization.
McLuhan was interested in media not as channels of communication, not as vehicles for conveying a meaning or idea from author to audience or from producer to consumer, but as environments. A medium will have an effect on us in virtue of the particular material and social changes that it engenders, irrespective of any individual messages that it is used to transmit. The impact of the telephone has been far [page 259] more significant than any of the specific uses to which it has been put.5 Media, which include for McLuhan an extensive range of technological innovations, touch us, affect us, alter us. The medium is the message, or perhaps the massage.6 Thus, in looking for the possible means of persuasion, for the ways that media work us over, McLuhan finds a rhetorical import and impact within the medium itself, rather than in the message or content it conveys. It is the pervasive, persuasive function of media to shape us—personally, politically, psychologically—by means of the environments that they create. It is this rhetoric of the environment with which we will be concerned, in order that we might examine the environmental rhetoric of digital games.7 Before doing so, however, it will prove useful to consider McLuhan’s account of the environments created by two of the most important media developments: literacy and print.
McLuhan was by no means the first to suggest that the development of literacy had a profound effect on culture and society, but the importance that he accorded this technological innovation, together with the particular approach he took to its impact, were novel.9 McLuhan argues that writing, as a medium, prompted the rise of civilization as we know it, and it did so because it shifted us from one environment into another. With the advent of literacy we moved from what McLuhan calls acoustic space into visual space. Acoustic space is the environment in which we live insofar as it is accessed predominantly by our sense of hearing. It is characterised, McLuhan argues, by inclusivity and a lack of central focus. “We hear equally well from right or left, front or back, above or below … We can shut out the visual field by simply closing our eyes, but we are always triggered to respond to sound.” (1960, 41). As Wordsworth suggested, “we cannot bid the ear be still” (quoted in McLuhan and Fiore 1967, 44). Thus, “The ear favours no particular ‘point of view’. We are enveloped by sound. It forms a seamless web around us.” (111). Members of those cultures who were dependent on speech and hearing for the majority of their communications, which is to say those who existed prior to widespread literacy, were accustomed to living in acoustic space. “Primitive and pre-alphabet people integrate time and space as one and live in an acoustic, horizonless, boundless, olfactory space” (57). Within this “sphere without fixed boundaries” (1960, 41) they experienced a rich, compelling connectivity with the world. With no central focus to this experiential sphere, an interplay between all the senses remained possible, a “tactile synaesthesia” [page 260] (1962b, 17). “Acoustic” space, then, entailed a kind of total inclusivity, an immersion within the environment.10 This unity was unavoidably lost with the arrival of literacy.
McLuhan argues that this technological innovation, particularly the phonetic alphabet, caused a shift in the relative significance of the senses. Writing promoted the eye rather than the ear. “Its use fostered and encouraged the habit of perceiving all environment in visual and spatial terms” (McLuhan and Fiore 1967, 44).11 This emphasis on the visual, and the insistence of the distinct, uniform characters of an abstract, phonetic alphabet, brought with it a new kind of separation, of segmentation, unknown to the inhabitants of acoustic space. Modes of perception and patterns of thinking became increasingly linear, distinct, departmentalized. Print exacerbated and extended this predominance of the eye and the fragmentation it entailed.12 The printing press, which McLuhan calls “a ditto device”, provided “the first uniformly repeatable commodity, the first assembly-line, and the first mass-production” (1962b, 124; McLuhan and Fiore 1967, 50). This mechanization of writing continued the process of abstraction begun by the individually meaningless characters of the phonetic alphabet. Crucially, the foregrounding or isolation of the visual, and the consequent “separative and compartmentalizing or specialist outlook”, tended to produce a “fixed point of view”, on which “the triumphs and destructions of the Gutenberg era” would be made (McLuhan 1962b, 126-27).13 McLuhan pins on printing a host of varied historical developments, including the rise of the nation state: in rendering the vernacular visible and unified, print “created the uniform, centralizing forces of modern nationalism” (199).14 This consolidation of the linear homogeneity of visual space was “the making of typographic man”.15 The culture of the West, the rise of this particular species of civilization, McLuhan suggests, was due in large part to the operation and effects of literacy: “Civilization is built on literacy because literacy is a uniform processing of a culture by a visual sense extended in space and time by the alphabet” (1964, 86).16
The Renaissance thus saw the creation of a new environment in which the visual ruled as tyrant. The “interplay of all the senses in haptic harmony” (McLuhan 1962b, 17), characteristic of oral culture and enduring into the age of the manuscript, was stamped out by the ditto device. Something of the seamless web of acoustic space was recaptured, however, with the onset of the “electronic revolution”. Telephone, phonograph and radio all extended the oral and acoustic, of course, but so too, McLuhan argues, did a congregation of other technological innovations: “even our visual electronic forms, the telegraphic press, teletype, wirephoto and TV are oral in character” (1958-59, 169). [page 261] Like the immediate communication between members of oral culture, the instantaneity of electronic communication, now on a global scale, created an “auditory spatial structure [which] is a simultaneous field of relations” since “the oral is accidentally the spoken but essentially the instantaneous”(169). The successive, linear segmentation accentuated by the visual supremacy of typography gave way to an instant electric inclusivity in which all the senses are involved, so that “[o]ur extended faculties and senses now constitute a single field of experience” (1962b, 5). With the electronic restoration of a tactile synaesthesia we become immersed within a new kind of acoustic space.17
The speed of communication in the electronic age renders the centralisation characteristic of the mechanical age redundant. Information moves too fast for any centre to keep up, ensuring that “[t]he new situation is not the old sponge pattern of intake from the margin and output from the centre, but of dialogue among centres” (1962a, 37). The “electronic conditions of implosion” thus create decentralized “centres-without-margins” (26, 23).18 As McLuhan famously suggested, this electronic, dialogic interdependence “recreates the world in the image of a global village” (1962b, 31). The multiple centres are brought into direct contact with one another, so that everyone is involved and connected with everyone else. “We live in a single constricted space resonant with tribal drums” (ibid.). This newly recaptured “tribal web” (1964, 84) does not ensure cooperation or conformity, however. In fact, the conditions of the “tribal-global village” (Stearn 1967, 280) produce more discontinuity, diversity and disagreement than the uniform consistency of visual space ever did.
Digital games illustrate McLuhan’s notion of a new acoustic space especially well, and provide thereby an opportunity to explore the utility of his particular understanding of the rhetorical effects of new media.20 Digital game genres are many and varied, but all such games create, as a result of their technological modus operandi, a distinct kind of environment which participating players must inhabit.21 Immersed within this interactive game environment, a player’s experience is qualitatively different not just from reading a text or viewing an image, but also from watching television or film.22 By inviting, or rather requiring of the player, an immediate engagement and connectivity with the medium, games are, in McLuhan’s terms, more acoustic than they are visual. Online gaming provides perhaps the best, or most obvious [page 262] example of the inclusive, decentred nature of digital gaming. In role-playing games such as World of WarCraft and Lineage, or action games such as Counter-Strike and Quake, millions of players from across the globe meet within vividly realised virtual environments, communicating and interacting instantaneously. In order to illustrate fully the acoustic quality of digital games, however, I would like to turn to an example from a rather different genre, a game which began life as an offline, single-player, turn-based affair, and which on first appearances seems, therefore, to be an altogether more visual experience.
Based in part on an intricate 1980s board game of the same name, Sid Meier’s Civilization was released by MicroProse in 1991. The computer game was initially only modestly successful but went on to secure a series of awards and increasing popularity. A new version, Civilization II, with tweaked gameplay and improved graphics, was released five years later, significantly increasing the number of players and prompting in turn two further expansion packs. Civilization III (2001) and Civilization IV (2005) followed, each time to widespread critical and popular acclaim within the games industry, making the series one of the most successful ever. The rise of Civilization has been unremitting and continues to this day.23
Players of Civilization start the game in control of a settler, the sole representative of their chosen tribe, in the year 4000 BC. Their immediate goal is to found a city, but from here the ultimate objective over the centuries to come is to establish a globe spanning civilization. Play unfolds on a huge world map which is gradually revealed over the course of successive turns. The game belongs to, and indeed helped define, the now-popular “4X” strategy genre: exploration (of the world), expansion (of your empire), exploitation (of resources) and extermination (of rivals).24 Players pursue their imperial agenda by founding additional cities, constructing military units, researching science and technology, building Wonders of the World, trading with competitors, etc. By these means players hope to “Build an empire to stand the test of time”, as the game’s original strapline urged (Figure 13.1).
Civilization, the game, seems to exhibit all the hallmarks of a visual form according to McLuhan’s schema, as his comments concerning civilization, the process, begin to suggest:
A goose quill put an end to talk, abolished mystery, gave us enclosed space and towns, brought roads and armies and bureaucracies. It was the basic metaphor with which the cycle of civilization began, the step from the dark into the light of the mind. The hand that filled a paper built a city. (1969a, 14)
[page 263]
Figure 13.1. Civilization IV Map
Most importantly, the game plays out on a map, that supremely visual medium which reduces all the world to a homogeneous, geometric space and entails thereby a kind of sensory blindness (McLuhan 1962b, 11).25 This playing area is, in effect, a sophisticated, animated board, not unlike those used for traditional board games, and the playing pieces are similarly restricted in their linear, sequential movement. The game even simulates line-of-sight for these units, a favoured point of view which permits players to see only those parts of the board which have been visited, and only those enemy units which are close-by (the so-called “fog of war”). Ted Friedman has argued that in simulation games like Civilization the map itself thus becomes the protagonist in a geographical narrative (Friedman 1999). Space is conceptualized by means of abstract images, and the games operate as maps-in-time, “dramas which teach us how to think about structures of spatial relationships” (ibid.). These structures are visual spatial relationships, of course, and the map’s movement through time accords with the strict linearity described by McLuhan. The game progresses in rigidly sequential turns: players must await their go, and must move each of their individual units one at a time, one after another. Even a tribe’s scientific development proceeds in strict order: any given [page 264] advance (wheel, gun powder, electricity, etc.) cannot be researched until prerequisite technologies have been mastered, and progress is represented by a branching, arborescent “technology tree”.26
Further, Civilization has remained, at least until its recent incarnations, an essentially single-player experience. Multiplayer functionality has been available since Civilization II, but the measured, turn-based pace and extremely lengthy course of each game has for the most part made the involvement of several players impractical.27 Just as, according to McLuhan, the alphabet and its mass-produced texts resulted in a largely solitary communicative experience, at least compared to the simultaneity of dialogic interchange, so Civilization gives rise to a predominantly isolated mode of play. Finally, in taking the role of a near-immortal sovereign, forging a homogeneous empire under their personal, direct command, players manage a highly centralized state.28 Those nomadic settlers with which the game begins swiftly set down roots, founding a capital city complete with imperial palace. The tribe becomes a nation, unified under absolute, central control.
Civilization is altogether more acoustic than it would initially appear, however. First, there is for the player no favored point of view. Where first or third-person action games like Counter-Strike or Tomb Raider require the player to assume a single, fixed perspective, Civilization allows continual access to any part of the world that has been revealed. There is thus no central focus, but rather equal perception in all directions.29 Further, despite the fact that your first city is a nominal capital, the cities that you go on to found are no less important in terms of the resources they exploit and the improvements they build. In the early stages of the game they can remain relatively autonomous, self-contained centres in their own right, but once conjoined by road or rail they form a network, a web even, of mutually supporting bases. This single space, resonant with the “tribal drums” of instantaneous communication, facilitates a dialogue among centres-without-margins.30 In McLuhan’s terms, then, the empire established by a tribe is not so much a centralized nation as a growing, mesh-like global village.
Moreover, there is a good deal more to the playing area, the space of Civilization, than the margin-free world map. Images may well be, as Friedman suggests, the clearest way to represent visual space, but an aspiring imperator must command more than a scenic view. In addition to the map, players also have access to a large number of charts and tables which relate all manner of essential information. Each “city display” conveys statistics regarding population, food stores, trade and corruption, building projects and improvements, and so on (Figure 13.2), whilst an array of advisors or “ministers” report on the nation’s defenses, relations [page 265] with foreign powers, the morale of the populace, the status of scientific research, etc. Play does not stop at the map-in-time, then, but incorporates numerous charts-in-time (Friedman 1999, n. 8), immersing the player in a multi-dimensional, acoustic experience. Friedman argues that digital games reorganize structures of perception by requiring players to internalize the logic of the program, to “think like a computer” (Friedman 1999). The immersive pleasures of an effective game of Civilization are due at least in part to the effortless, instantaneous way in which an experienced player will begin to access and manipulate the heterogeneous maps, charts and tables.31 Players come to identify not with the tribal leader they purportedly control, but rather with the roles and functions carried out by the game itself. The player perspective is not that of a God’s eye view, a prospect from above which surveys a uniform, geometric visual space, but rather of a computer, an exploration from within the sphere of instantaneous electronic communication. Just as there is no single geographical centre to the player’s expanding empire, so there is no single, privileged subject-position for the player who is dispersed across a varied and changeable acoustic environment.32
Figure 13.2. Civilization III City Display
[page 266] McLuhan argues that the sheer volume and diversity of information with which consumers are faced in the electronic age necessitates a “producer-oriented” approach whereby they become discriminating co-creators of their own media experiences (1958-1959, 167). The particular kind of interaction in which player and computer engage certainly requires that the former take a proactive part in the construction of the gaming experience. Immersion within the medium of the game ensures that the process of play is no hermeneutic matter of discerning Civilization’s “message”. The environment, both geographic and otherwise, changes during the course of the game as a direct result of the player’s actions. Terrain is mined or irrigated, taxation is raised or reduced, governments are replaced or restored. The game continually demands decisions of the player, at both local and global levels, and every one will have consequences for the success of the tribe, sometimes within just a year or two of game time, sometimes decades or centuries later.
At the same time, David Myers has further argued that it is precisely the “transformative” aspect of Civilization’s gameplay that makes it such a compelling experience (2005). With each technological advance, with each change in government, and especially as the powerful Wonders of the World are secured by one tribe or another, the rules of the game are significantly transformed, requiring players to reassess their immediate goals and perhaps modify their style of play. A full understanding of the far-reaching effects of these transformations can only be gained by replaying the game, and by experimenting with different strategies and tactics, many times over.33 The recursive nature of replay, the experimental adaptation that comes with successive iterations, results in an acoustic space which is never consistent but always involving.34
Players are submerged, then, in an environment which moulds their actions, prompts their responses, works them over: the medium is the massage. But at the same time, as we’ve seen, they work to shape their environment, actively modifying their surroundings, pursuing “the tilling of virtual landscape” in the broadest sense (Myers, 2005). Players are not subsumed into or absorbed by this virtual, acoustic environment, and thinking like a computer need not mean that we become one with the software: there is still a useful distinction to be drawn between the masseur and those massaged. Players of Civilization exist within the game environment, experiencing a rich, compelling connectivity with the world, but, engrossed as they may be, connection is not assimilation.35 If the medium is the message, the directive or intimation here is that the player is an active, involved part of the environment. Every decision will impact on the state of the game, provoking consequences which the player will in turn experience.36
[page 267] Digital games, including the seemingly linear and visual Civilization series, provide an illuminating illustration of McLuhan’s notion of a new, inclusive, acoustic space. Players are immersed in an engaging, centre-less, electronic environment. Strictly speaking, if we are to follow McLuhan, an individual game such as Civilization simply illustrates this environment: each time we take up Sid Meier’s challenge we invoke in miniature the wider acoustic space of which the medium as a whole is a part. Digital games in their entirety comprise one contributing component of the distinctive acoustic environment which has emerged since the nineteenth century with the advent of telegraph, radio, television, et al. McLuhan thus provides a productive probe with which to explore digital games, but, at the same time, close examination of this particular electronic medium helps to clarify our understanding of the new acoustic space to which he draws our attention. The inclusivity and immersion that characterize acoustic space should not be conceived as an assimilation or absorption of individual subjects into that space. Notoriously compelling as Civilization is, and much as the game works us over personally, aesthetically, even psychologically, the player, like the denizens of the wider acoustic space, remains an active participant within the environment.
In his analysis of Civilization, Myers’ focus on the transformative, recursive nature of gameplay accords closely with McLuhan’s insistence on the necessity of analysing media as environments rather than as vehicles or channels of communication. Both writers distance themselves from textual analysis, concentrating instead on the internal mechanics and physical or psychological effects of their chosen media.38 Myers goes so far as to suggest that, in general, game backstories, the carefully realised social and cultural milieus in which game events take place, “have no real relevance to computer gameplay” (2005).39 What matters is “not the setting or the characters or the plot, but the relationships among the game’s signs and symbols as adjudicated by the game rules” (2003a, 9). In fact, Civilization’s particular representation of world-historical development, its backstory in the broadest sense, has been the subject of much discussion and ideological critique. In this final section I would like to explore the explicit but equivocal environmental rhetoric of the game. Conflicting textual analyses seem to suggest, I argue, that it is important to attend here not just to the message but to the medium itself.
Civilization’s rhetoric with regard to environmental issues is, on first sight, unpromising. Even setting aside the imperial and colonialist [page 268] objectives which players are required to take up,40 and the peculiarly occidental assumptions regarding cultural and governmental progress—factors which between them have borne the brunt of criticism from the game’s always-respectful detractors (Stephenson 1999; Henthorne 2003; Poblocki 2002; Lammes 2003; Bitz 2002; Douglas 2002)41—Civilization’s approach to ecological questions remains problematic. At the start of play a tribe’s nomadic settlers find themselves amidst virgin landscapes: lush plains and grasslands, dense forests and arid deserts, hills and mountains, swamps, jungles, and more. Once settled, however, and as the expanding tribe establishes one city after another, the terrain changes. The land around each settlement is developed: roads are laid to connect urban centres, fields are irrigated beside available waterways, hills are mined. As technology advances, railroads begin to criss-cross an intensively farmed landscape. Gradually but inexorably the diverse natural environment is replaced by an increasingly homogeneous topography, a highly developed, uniformly industrial conurbation. Only by means of such expansion and cultivation can players hope to survive and succeed.
One might argue that there is an implicit environmental message here: Civilization draws the player’s attention to the fact that increasing urban settlement does deplete and destroy the surrounding land. There is a lesson here, perhaps, that the demands of concentrated population growth directly counterpose environmental concerns. And in fact swelling populations and escalating production present players with a particular new problem. The accumulating factories, offshore platforms, manufacturing and power plants, all increase the likelihood of environmental pollution. Represented as a death’s head skull, or a garish blight on the land, pollution not only lowers a player’s final score, but nullifies the benefits that industrialization and intensive farming had initially bestowed. The problem of pollution persists as the game progresses and, if left unchecked, can lead to global warming, rising sea levels, and barren coastal farmlands. Only by constructing city improvements such as solar and hydroelectric power plants, recycling centres and mass transport systems, can the threat of pollution be averted. Nuclear power stations reduce the likelihood of immediate pollution, but bring the possibility of a ruinous meltdown, and the deployment of nuclear missiles has similarly devastating effects. If there is a textual message to be detected within Civilization it is surely that wilful disregard of the environmental consequences of your actions results in dire costs and penalties.42
And yet, pollution is just one obstacle among many which must be addressed by the player whose key objectives are, as we’ve seen, exploration, expansion, exploitation and extermination. There is certainly no [page 269] incentive to reduce the consumption of resources, or, indeed, to regard the game’s geography as anything other than a storehouse of goods and material opportunities.43 It is in fact a simple matter to “clean up” polluted terrain: teams of engineers or workers assigned to the task swiftly remove all evidence that a problem ever existed. Even nuclear fallout, from missile or meltdown, can be scrubbed from the map in a few game years.44 Though repeated cleaning can become tedious in gameplay terms, the implication is that environmental pollutants, nuclear or otherwise, are an easy matter with which to deal. Indeed, along with civil unrest, corruption, waste, and a number of other elements considered detrimental to smooth gameplay, pollution was removed from Civilization IV in favour of a streamlined “city health” system, shifting the ecological focus from global environment to metropolitan wellbeing.
In Ecospeak, Killingsworth and Palmer defined rhetoric as “the production and interpretation of signs and the use of logical, ethical, and emotional appeals in deliberations about public action” (1992, 1). Interpretation of the signs that are produced and manipulated within Civilization seems to yield an ambivalent message. Player deliberation about public action, about choices concerning development and growth within the game, will be informed by a rhetoric which seems both to acknowledge and elide environmental concerns. If we are interested in the game’s possible means of persuasion, in the ways in which it massages and works us over, however, we might do better to attend to the medium rather than the purported message. Over the course of the decades and centuries, players experience, by virtue of their immediate and engaged immersion within the game environment, the direct and long-term consequences of their own actions. Not just the decisions they make concerning industrial growth and development, but every unit or building they construct, every adjustment they make to taxation or scientific research, every trade or diplomatic negotiation they pursue, will impact on the way in which the game ultimately plays out. Players are participants, actively involved in the medium-as-environment, experiencing firsthand a compelling connectivity with the world. This is the key environmental rhetoric of the digital game Civilization, the message of the medium.
Raymond Williams suggested, or perhaps hoped, that the “particular rhetoric of McLuhan’s theory of communication is unlikely to last long” (1974, 128). The McLuhanacy of the 1960s and 1970s did indeed pass, but as Gary Genosko observes, at the start of the new millennium we find ourselves immersed in a McLuhan renaissance. Is this renewed interest warranted? Does McLuhan’s work speak to the electronic revolution he envisaged? The utility of McLuhan’s provocative writings lies, I think, at least within the context of environmental rhetoric, with his [page 270] insistence on the complicated relations that pertain between the visual and the acoustic. The temptation to sensory blindness, to conceiving digital games as a primarily visual medium—linear, uniform, characterised by sequential segmentation—is contested by their irresistibly acoustic qualities, their inclusive, immersive, decentred interactivity. In the sensory interplay of this digital, acoustic space, participants are engaged and implicated in the suasive rhetoric, the medium as environment, which touches, affects and alters them. McLuhan’s own rhetoric will more than likely stand the test of time, precisely because he left open exciting and productive doors, provided rich and largely untapped theoretical resources, through which we might yet address acoustic and visual questions of ecospeak and ecosee.
Tom Tyler is a Senior Lecturer in Communication, Media and Culture at Oxford Brookes University, UK. His current research interests include media ecological approaches to communication technologies, especially digital games, and the uses to which inhuman animals have been put by philosophy and cultural theory.
More essays by Tom Tyler are available at his Research page.