A personal journey is at the heart of W. Brian Arthur's book The Nature of Technology: What It Is and How It Evolves.  When Arthur enrolled in electrical engineering, he was aware that he did not quite understand the nature of the technical field he was studying. He moved on to mathematics, economics, and operational research. Now, over fifty years later, after a distinguished career at Stanford University and a long association with the Santa Fe Institute, Arthur has come full circle to address the question he had as a young student.
Arthur defines technology as nature organized for our purposes. Technology is what we desire it to be according to our needs, within the opportunities and limitations of nature. Would that do?
As the subtitle of the book points out, Arthur's examination of technology comes in two parts: one concerns its ontology, the other its evolution. The two parts offer different but intertwined levels of understanding.
Technological evolution is usually considered linear, as in Ray Kurzweil's The Singularity Is Near, for instance.  Arthur argues that the picture is far more complex, involving modular, combinatorial, and recursive aspects. Arthur relies on a wealth of examples to argue that technologies function as modules or components that can be assembled in novel ways to produce new technologies out of the recombined parts. And each technology hinges on previous ones in a recursive way, like Russian dolls fitting one inside the other.
This view of technology could still yield linear histories, if it were not for the unpredictable formation of niches that create pockets of opportunity for the rapid redeployment of previous technologies in the service of an emergent new one that is favorably received. Arthur's previous research in economics comes into play quite effectively, through the phenomenon of increasing returns. Sixteen years earlier, in Increasing Returns and Path Dependence in the Economy,  Arthur showed that as an economic feature or product gains a special advantage, a flow of positive feedbacks could propel it past other existing features or products until it dominates a market through no extraordinary talent of its own except that it got lucky. The implication is that the economies, systems, or products that come to dominate a market might not be necessarily the optimal ones for the issues at hand. They grow out of proportion over other suitable alternatives, driven by an internal market dynamics of positive feedback.
Increasing returns seem to contradict the more classical notion of free market rationality. It shows that the overall invisible hand at play in free markets is a rather idealized model that breaks down at scales where the phenomenon of increasing returns can trigger disruptive niches that grow like a pearl around an imperfection until they come to dominate and monopolize economies. They also form bubbles that eventually burst. These various and unexpected spikes in development disrupt the model of linear technological evolution.
Arthur argued, however, that consumer heterogeneity produces a diversity of economic needs, which ultimately counters the formation of monopolies and helps re-tune an economy as it continues to evolve. Nurturing diversified preferences would keep in check the formation of such bubbles. In fact, as we saw in the dot-com and the housing bubbles of this past decade, a bubble develops in an economy when people begin to synchronize and head in the same direction rather than preserve diversity as independent agents.
Individual preferences affect technological evolution, and this interaction is not a mere imperfection that can be factored out. Consequently, human purpose plays an important function in the nature of technology itself: it is at the root of novelty.
Stuart Kauffman, a former colleague of Arthur's at the Santa Fe Institute, published an inquiry in 2000 into novelty in nature, entitled Investigations.  Puzzled by the ubiquitous presence of innovation in nature, he set out to find a law that could explain this phenomenon. His work remains incomplete. Nevertheless, without going to the extreme of thinking that there is an actual law in nature that drives novelty, Kauffman noted in his book some features that found their way into Arthur's work in the area of innovation. Kauffman suspected that ecosystems occasionally reach critical states that push them beyond their boundaries into what he called the adjacent possible. Agents in the ecosystem would for some reason push beyond their confines and enter a new proximal region where previous techniques no longer quite applied. Novelty would then be a result of the need to adapt to the new environment. The problem for Kauffman was that he could not come up with a model to show consistently how agents in an ecosystem would suddenly push beyond their confines. Kauffman, understandably, wanted to avoid randomness as the foundations for novelty in nature, since innovation seems to be more than the consequence of arbitrary acts.
Arthur imagined technological innovation using people as agents and derived a reasonable solution. People behave in unpredictable yet non-random ways. They are the ones who tend to push beyond established norms, the way explorers sail into unknown territories that they imagine somehow familiar. Henry David Thoreau famously portrayed this human phenomenon in the image of a man losing pace with his companions because he hears a different drummer. Since technology is a human phenomenon, Arthur used human agency as the engine of diversification to push into Kauffman's adjacent possible spaces.
What is it that makes human agency diversifying? I took up this more fundamental question in "Reflections on Interactivity"  and argued that it is play. Play catalyzes novelty, even within the confines of rule-based games, because there is always a leeway, a play zone, where personal agency and preferences can produce surprising outcomes. In "Creation by Looping Interactions,"  I illustrated how play takes systems into Kauffman's adjacent possible spaces. It turns out that such adjacent spaces are equivalent to what Russian psychologist Lev Vygotsky called zones of proximal development in education.  These are zones in which mentored students can play, bringing in their own ideas and potentially setting the stage for unexpected innovations.
Arthur describes innovation in technology as an adaptive stretch. It is a stretch into such adjacent zones where development can happen. And it is adaptive in the sense that previous technologies need to readapt after they recombine and help break new ground. Arthur proposes that innovation can happen in two ways. The interplay of existing technologies can eventually lead to emergent new ones. This tends to happen in institutions where research goes on for its own sake, so to speak, and is self-driven or at least rather independent from external directives. The other possibility is the purposeful intervention of human agency that recombines technologies in order to achieve desired goals and carry out needed tasks. In this second case, technologies are developed in order to serve our purposes. As we integrate a diversity of personal preferences, styles, and needs into a shared purpose, we use such directives to tinker with existing technologies until solutions emerge to carry out desired tasks.
By virtue of technology being recursive and combinatorial, Arthur's argument stretches back to the imagined origins of technology and forward to the present. Human agency interacting purposefully with phenomena gives technology its nature.
Argentine writer Julio Cortázar wrote, in Último round, a brief history of technology entitled "El Tesoro de la Juventud."  This hilarious reverse history begins with recent technologies in sea, land, and air transportation. It works its way forward to the increasing convenience of flying at lower altitude to better appreciate the landscape, to the bicycle as far superior in this respect, and then to the invention of walking, which seems to defy efforts of the imagination to surpass its convenience. Travel by sea leads to the parallel breakthrough invention of swimming. Such comic, deliberately absurd chronology underlines the function of desire in technological progress. What propels Cortázar's playful history is the caricature of a relentless human appetite for safer, simpler, more intimate forms of transportation, until in the end, driven by child-like simplifying logic, we turn out to embody all the technology needed to do what we like best.
There is a similar reversal from an entirely different perspective in Cormac McCarthy's The Road.  Civilization has been undone, leaving behind broken forms under a constant drizzle of ashes. In a harrowing landscape in which scattered survivors tend to prey on one another, a father leads his son on a journey to the sea so that they might survive another winter. They use technological scraps found along the road to stay alive. The dying father keeps telling his son that what matters most is to keep the flame alive: to carry a fire within, and pass it on. They finally reach a beach. It is empty except for a few faint embers of humanity that also managed to make it this far down the road.
The ability to handle fire may well have been humanity's first technology. Ironically, ashes in The Road reveal that fire, which technologically got us this far, brought humanity's journey to a sad end. After technology regresses to its origins, what remains is an artistic and spiritual impulse: fire transformed into the most basic metaphor of warmth and hope -- much like discovering the joy of walking.
Arthur proposes that human needs drive technological developments. Innovations that propel its evolution do not come only from within, from recombinant possibilities, but also from without, from purposeful human interactions. This makes the direction of technological evolution inherently uncertain. Cortázar and McCarthy play with the extreme possibilities that underscore the unpredictability of technological futures.
We might imagine that technology could eventually override our caprices and forge ahead, entraining us in a rational direction. The problem is that neither an advanced technology, nor we ourselves, could optimize any such direction. Optimal and rational solutions are impossible in our complex, highly interactive environments.
Over forty years ago, Herbert Simon addressed the impossibility of optimizing in complex systems, from marketplaces to cultures. He was awarded a Nobel Prize in Economics for contributing to decision-making theory with concepts of bounded rationality and satisficing -- a neologism to contrast optimal decisions with ones that are less perfect yet are satisfactory and sufficient for their purposes. Arthur's view of technology rests on these earlier insights. Like Simon, Arthur stresses that technology does not optimize: the ideal of perfection in technology yields to a messy vitality that is closer to its nature.
In The Sciences of the Artificial, Simon had also noted that human preferences drive design in the professions, from engineering to the sciences.  Beyond desires, the other factor that influences designs is the domain in which they operate. Arthur follows this lead. He gives the example of Paul Klee, who noted that the artist adapts to the medium used. Or as Picasso put it more abruptly: painting wins in the end.
Technology's messy vitality lies in the playground in which human desires and existing tools interact to form new combinations. In this zone of proximal development, in this adjacent possible, adaptive stretches shape technologies to the purposes of our imagination.
The Nature of Technology ends as a model of what technology might be. It underscores the idea that, since human purpose drives technology and not the other way around, we have to see in it more than deadening comfort and convenience. Technology can alienate us from what makes us human or it can affirm our humanness, stresses Arthur. The technology we get hinges on what we wish for. This keeps us in the loop of the mechanisms of technological evolution.
Such participation requires more attention. A sequel to Arthur's study could be a more in depth exploration of human intervention in technological developments. This was the direction that Simon initiated with his pioneering work in decision-making processes, and then began to transfer from economics to other fields, like psychology and design, through what he envisioned as our sciences of the artificial.
Transfers across disciplinary boundaries have to happen more vigorously. These interactions are gaining momentum. For instance, ecological concerns are at the forefront of steering towards greener technologies. Philosophical arguments over open source have spawned surprising innovations such as Wikipedia and cooperative software development. In medical technologies there is an increasing concern over quality of life and a growing awareness of the complexities of interactions between patients and treatments. The invisible hand of economics is becoming more and more human. Across the board in the sciences, human agency is seen as playing an increasingly defining role in picturing a world no longer idealized and fixed.
What enables such human intervention in technology? What makes it possible beyond wishful thinking? A new language may be emerging which embraces our previous ones and loops them into a more effective and reflective interactive ensemble. Advances in areas of simulation and modeling may well be helping us reflect on how to fashion more human, ecological, and effective technologies across all disciplines. And technology enhances this development that impacts on itself.
The stories we tell affect our future. This brings arts and cultures into the picture as constitutive players in shaping technology. A sequel to The Nature of Technology might explore this underrepresented yet essential interaction. For now, we continue to cultivate narrative gardens with the languages of our diverse cultures and disciplines, the languages of our institutions and techniques. In the process, we enhance modeling techniques, from the arts to the sciences, from engineering to design, that might help us steer in the direction of what we wish to become.
Whose direction will that be? Human interactions are complex and dynamic. Technology might help weave a shared destiny that emerges from our differences and preserves our individual agency. It could be technology's evolving nature as well as ours. We go hand in hand.
 W. Brian Arthur, The Nature of Technology: What It Is and How It Evolves (New York: Free Press, 2009).
 Ray Kurzweil, The Singularity is Near (New York: Penguin Publishing, 2005).
 W. Brian Arthur, Increasing Returns and Path Dependence in Economics (Ann Arbor: University of Michigan Press, 1994).
 Stuart Kauffman, Investigations (Oxford: Oxford University Press, 2000).
 Luis O. Arata, "Reflections on Interactivity," Rethinking Media Change: The Aesthetics of Transition, eds. D. Thorburn and H. Jenkins (Cambridge: MIT Press, 2003), 217-225. This is a reprint of "Reflections about Interactivity," presented at the inaugural Media in Transition conference in 1999 at MIT, http://web.mit.edu/comm-forum/papers/arata.html (accessed on 27 February 2010).
 Luis O. Arata, "Creation by Looping Interactions," M/C Journal: A Journal of Media and Culture 5, issue 4 (August 2002), http://journal.media-culture.org.au/0208/creation.php (accessed on 27 February 2010). I extended this study of play in "Interaction, Innovation, and Immunity: Enabling Agents to Play," AAAI 2004 Spring Symposium Series (Menlo Park: AAAI Press, 2004), 41-46, http://www.aaai.org/Papers/Symposia/Spring/2004/SS-04-03/SS04-03-008.pdf (accessed on 27 February 2010).
 L. S. Vygotsky, Mind in Society: The Development of Higher Psychological Processes (Cambridge: Harvard University Press, 1978).
 Julio Cortázar, "El Tesoro de la Juventud." Último Round (Mexico: Siglo XXI Editores, 1969), 23-28.
 Cormac McCarthy, The Road (New York: Vintage, 2006)
 Herbert A. Simon, The Sciences of the Artificial third edition (Cambridge: MIT Press, 1996).