Since the dawn of the space age, humanity has dreamed of pushing ever farther and faster, exploring the Universe around us… and has run aground on the limitations of human technical progress and the vast cost of such an endeavour. One response from writers of science fiction has been to reimagine humanity as opportunist engineers, able to adopt, understand, modify and often improve upon alien technologies. This activity - retroengineering or reverse-engineering - has some real world precedents but to what extent are they applicable elsewhere?

Technology as salvage

Perhaps the most common SF scenario in which alien technology is adapted by humans is one in which they salvage the debris, detritus or ruins of alien technologies which have been left behind. Here the aliens themselves have little or no input into the process of salvage. Human scientists are required to reconstruct the technology based on textual evidence or by direct inspection - the use of science as a universal language to aid translation of both texts and tools. Alternatively the equipment is simply used based on guesswork of the “it looks like a weapon so let’s point it and push the button” variety [1]. Examples of this type are numerous and range across a broad spectrum in both scope and plausibility.

They also started early: H G Wells’ The War of the Worlds (1897) littered London and the Home Counties with defunct martian machinery. While some latter-day sequels have extrapolated human attempts to use this debris into a full steam-punk alternate history, notably the Scarlet Traces series (2002-2017), most are vague regarding the adaptation of the technology itself and suggest the need for some insight from captured or surviving martians - and at least the human investigators here had the advantage of having seen the technology in action rather than having to infer it from form alone. It’s interesting to note that both the idea of retroengineering this technology and a recognition of its risks actually goes all the way back to Wells himself - the novel epilogue notes that:

Neither is the composition of the Black Smoke known, which the Martians used with such deadly effect, and the generator of the Heat-Rays remains a puzzle. The terrible disasters at the Ealing and South Kensington laboratories have disinclined analysts for further investigations upon the latter. - Epilogue, The War of the Worlds (Wells 1897).

This idea of humans exploiting alien salvage has recurred in SF ever since. In the novel Marrow by Robert Reed (2000), humans take ownership of a huge and abandoned alien construct, one large enough to hide a Mars-sized planet in its core. They use this ship to transport and house other alien species, exploiting its inbuilt technologies. In this case, much of the drama relates not to the early stages of first contact with the ship, but instead to a much later exploration of its hitherto-unsuspected internal features, and the consequences of that exploration. Reed takes a less scientifically-rigorous approach to creating his world than earlier authors such as Wells or Clarke, whose Rama series is a clear influence on Marrow [5], but instead focuses on exploration of a culture that has grown up under the influence both of human-developed near-immortality and of the alien technology.

Not every salvaged technology is on the megastructure scale, however. A still-titanic but less astronomical scaled alien artefact is the humanoid mecha in Sylvain Neuvel’s Themis Files series (2016-2018). This device, a huge robot controlled by the physical movements of human beings embedded within it, was sundered into a number of parts and scattered across the Earth. Across three novels Neuvel follows the efforts of a human team to trace and reassemble the components, and then to control the robot while also exploring its origins. In terms of the process of retroengineering the approach here is very similar to that of long-running film and television series Stargate: SG1. In that series a human military organisation becomes experts in exploiting first the abandoned technologies of the alien Goa’uld (described as responsible for the Egyptian pyramids and leaving numerous behind when the aliens were thrown off Earth) and then of the Ancients (who originated Atlantis myths and are believed to be long-extinct).

The use being put to the technology in the Themis Files and Stargate is very different; in both cases though, organised and government-funded teams of human scientists and engineers strive to understand the alien equipment and its underlying principles, but the key technology is essentially exploited on a trial-and-error basis, or following instructions on translated texts. There is no real prospect of recreating the devices in question or replacing them should serious damage occur. Here humans are shown using great ingenuity, and deploying edge cutting-edge science, but ultimately doing little more than scraping around the edges of a technology that continues to lie beyond their understanding.

In parallel to these virtuous and scientifically-driven endeavours, there is a strand of science fiction which takes a more cynical view of human nature and its response to such opportunities. In these, human beings are shown as profit-driven scavengers, using alien technology with little or no understanding of its underlying principles, and little or no attempt to develop such understanding.

A vast alien starship is salvaged by freedom fighter Roj Blake in television series Blake's 7 (BBC 1978-1981) and named the Liberator. Despite having no real understanding of its operation, Blake and his crew use the vessel and its associated technology (such as teleportation bracelets) to establish a tactical superiority over the Earth Federation. This series revels in the moral ambiguity of its characters, contrasting the amoral minor crimes of its petty criminal main cast with the more legal but ominous and corrupt uses the authoritarian Federation might make of the same opportunities.

Alastair Reynolds’ novel Revenger (2016) and its sequels demonstrate a still less virtuous scenario. In this fairly grim story of the distant future, not just alien technology but their physical remains are scavenged by human beings, with little idea of how they work. Biomechanically enhanced skeletons of long-dead aliens are used to facilitate a form of interstellar psychic communication network, while the ruthless and piratical crew of the central starship make their living searching out “baubles'' - caches of technology left behind by both alien civilisations and ancient human cultures [6]. Much of this technology is lethal (as much to the scavengers as its users), is sold on the black market, and again is used by trial and error without detailed physical understanding, or even serious attempts to develop such understanding.

A still more cynical attitude can be seen in the earlier novel Roadside Picnic by Arkady & Boris Strugatsky (1972). Written in the Cold War Soviet Union, it has a near-contemporary setting, but describes a world that has been shaken by the sudden creation of lethal zones of contamination as a result of a fleeting alien visit [2]. A research organisation exists outside at least one such zone, sending official missions in to recover discarded alien devices for investigation, but again there is a thriving black market which inspires illegal “stalkers” to make dangerous, and often fatal, trips to raid the zone for alien equipment. Unlike many of the other examples mentioned thus far, this book includes detailed and explicit discussion of both the practical and philosophical aspects of this situation. As one character notes:

“We’ve found many marvels. In a number of cases, we’ve even learned how to adapt these to our needs. We’ve even gotten used to them. A lab monkey presses a red button and gets a banana, presses a white button and gets an orange, but has no idea how to obtain bananas or oranges without buttons. Nor does it understand the relationship between buttons and oranges and bananas” [...] “There are a number of objects for which we have found applications. We use them, although almost certainly not in the ways the aliens intended. I’m absolutely convinced that in the vast majority of cases we’re using sledgehammers to crack nuts”
- Roadside Picnic (Arkady & Boris Strugatsky, 1971, trans. Bormashenko, 2012, SF Masterworks edition, p.136)

The premise here is that simply figuring out a use for an alien technology is not the same as truly understanding it, and that without guidance or a true appreciation of the technology, humanity may end up doing the equivalent of using nuclear fuel rods as a blunt object to hammer nails.

Technology as a challenge

A related concept to technology-as-salvage is that of alien technology presented as a deliberate challenge. Again, in this case, humans are required to interpret technical equipment or notation without assistance from their alien originators. However in this scenario, doing so forms part of a test, giving successful humans (or indeed any other alien) access to additional resources, or even access to an entire interstellar community.

There are a number of instances of this kind of technology-threshold challenge in the Stargate universe, particularly in later series, as the acquired scientific knowledge of the characters improved. Notably the Asgard, an alien race identified with both the norse gods and the “greys” of Roswell fame, presented technological tests as an alarm system to attract their attention, although this was aimed at a somewhat more primitive threshold level than our current technology, rather than a higher one [3]. Similarly the Star Trek universe features examples of this trope, with a memorable instance being “Arena” (ST:TOS, 1967), in which an alien race (the Metron) pitch representatives two others (humanity and Gorn) into a battle for survival in which it requires technical knowledge and ingenuity to improvise a weapon and win the conflict. Again, in this case the test was set below our current level of understanding, requiring the construction of simple devices from advanced knowledge. This might be a pragmatic acknowledgement of the difficulties of the reverse, A story in which the characters repeatedly failed to meet the standard might well be less than enthralling.

An interesting example of a more advanced (and slightly less serious) alien technology test can be found in the 1950s American radio drama anthology X-Minus-1. The episode “Double Dare” was broadcast in December 1957, and based on a short story by Robert Silverberg which had appeared in Galaxy magazine the previous year [4]. In this story, two human engineers get into a bar-room argument regarding whether human or Domerangi technology is superior. The result is a competition in which they, and a pair from the planet Domerang V, are separately required to reproduce technologies that they are shown. Whichever race is able to complete all the challenges will be acknowledged as superior. I won’t give away the ending (it’s well worth a listen or read), but it’s fair to say that the engineers consider the requirement to reverse-engineer a device based on inspection alone a fair and achievable challenge.

Clarke’s Third Law

It is undeniably true that reverse-engineering the work of rival companies has long been a normal part of industrial and technological development. Whether simply by inspection or through dismantling and reconstructing devices, engineers and scientists have been able to produce analogues and thus catch up with competitors. The same basic principle also applied to military technology for much of the Cold War period of the twentieth century - where espionage was unable to extract the original plans for innovations, teams worked on studying the physical objects (or even just photographs of them) in order to deduce the underlying principles and their new applications.

There have also been instances of science fiction being used as the subject matter for retroengineering. It is well known that designers of both telecommunications and medical equipment claim to have been inspired by devices shown on screen in the Star Trek universe, for example, although it is debatable whether this inspiration is more than cosmetic. Science fiction as a genre exists to consider future developments through logical extrapolations from the present, and it’s hard to determine whether devices with the same functionality would have been developed regardless of the fiction (as the fiction itself had originally predicted).

So reverse-engineering of technology is clearly possible up to a point. However there’s an important caveat to consider here: all of the practical examples we can point to up to now have involved humans interpreting technologies based on mutually understood scientific principles, with a common set of electronic components and circuit conventions, and a similar level of technological development. This is a very, very different scenario to most science fiction examples of retro-engineering, which are described as more akin to handing a defunct iPhone to an engineer from the early nineteenth century. Without breakthroughs in understanding electromagnetism, circuits couldn’t be developed, electricity would have remained the subject of carnival shows and the concept of electronic telecommunications would not have been invented. Without breakthroughs in optics and quantum mechanics, transistors couldn’t be invented, high magnification microscopy would never exist, and those transistors could not be miniaturised. Without thousands of microscopic transistors packed on a silicon wafer, the computer chip would not exist. The iPhone (or other smartphones) represents a technology so far divorced from the early stages of industrial development that neither its function nor its components would be accessible by visual inspection alone.

This kind of scenario was discussed by science fiction author and futurist Arthur C Clarke in an essay in Profiles of the Future (1974 revision). Here he asserted that “any sufficiently advanced technology is indistinguishable from magic”. In other words, without the scientific background and history of technological development required to interpret a device, all one can do is shrug and describe its operation as fundamentally unknowable. The consideration all science fiction involving retroengineering has to face is to determine what constitutes “sufficiently advanced” in this context. Are our current insights into scientific development already sufficient to explore any technology we encounter? If our understanding of electromagnetic circuits is already well enough advanced, every circuit we encounter should be based on the same fundamental principles and thus, in theory, interpretable, regardless of its origin. On the other hand, if we are still working on the limits of some deeper theory, it is more than likely that in two centuries time our understanding will be considered as outdated as that of our early nineteenth century engineer.

We can also ask deeper questions about the role played by human physiology and psychology in our application of scientific principles. Our technology is shaped by our perception of the world, whether that involves the limitations of our detection of light or the approach taken in manipulating fundamental forces. Already, here on Earth, research is ongoing into the cultural specificity of scientific knowledge and its implementation. This suggests that even between cultures with the same physiognomy, psychological differences can prove a real and ongoing barrier to understanding. A truly alien technology may be built from an entirely different perspective, and even contain components whose existence we are unable to perceive, or to grasp conceptually. It could lie not just temporarily out of our reach, but forever so.

We shouldn’t underestimate the ingenuity of human engineers. Reverse engineering is not only possible but has been demonstrated numerous times. However, we must recognise that the optimism of Silverberg’s “Double Dare” may overlook the extent to which alien technology (if it exists) may lie beyond our reach. The prevalence of such stories in SF literature may speak more to the supreme confidence (or even arrogance) of modern western scientific culture than to reality. In truth, any attempt we make to exploit such technology may well be equivalent to ancient sorcerers calling on capricious demons to solve their problems, and could indeed be an example of using sledgehammers - or nuclear reactors - to crack nuts.