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Adam Jacobson
3 December 2012
Homo Melior?: Prostheses, Cyborgs, and the Future
Transhumanism, a loose movement of philosophers, engineers, computer scientists, and
assorted other futurists, aims at the remodelling of the human condition. ‘Let us take evolution
into our own hands,’ goes the proposal, ‘and move beyond the limitations of humanity as it
currently stands to become something more, trans-human.’ Many projects aim towards aspects
of this majestic and somewhat blasphemous goal, in areas from artificial intelligence to
biocomputing to medicine. At its most physical, though, transhumanism is concerned with
making direct changes to the human body itself in the form of prostheses, which replace
functionality found in the existing human body, and augmentations, which grant the bearer
capabilities not previously possessed by humans. By the application of such technology,
humanity may become cyborgs, simultaneously man and machine, more, at least in physical
form, than human. This paper aims to conduct, with an eye to transhumanism and the creation
of cyborgs, a cursory survey of prosthetics and augmentations, examining both what is
presently possible and what is likely to be possible in the near future, as well as the
ramifications and implications of such technology.
Although the transhumanist project is a relatively modern movement, prosthetics
themselves are nearly as old as humanity itself. Walking sticks and crutches, for example, have
been used for millennia to compensate for missing or damaged limbs, thus functioning as
extremely basic prosthetics. More functional, and simulational, in that they aim to copy the
replaced body part in form as well as function, prosthetics, such as wooden legs, are equally
historic, with the oldest known prosthetic leg, produced by the Romans, dated to “around 300
B.C.” and the oldest prosthetics of all, two big toes of ancient Egyptian manufacture, dated to
nearly 1000 B.C. (Lorenzi TK add to bibliography) In more recent times, the variety of
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prosthetics available has expanded immensely, with replacements of varying degrees of fidelity
to the organic on offer for many an organ. Bones, especially, have been long established as
replaceable; the first hip replacements, for example, took place in the “late 1800s,” with
successful replacements performed on many other joints in the body over the next century.
(Manderson 59) Indeed, the field is so well established that most recent progress has been in
merely the composition of the implants themselves, with a steady progression of incrementally
improved artificial bones made from “plastic, cobalt, chromium and titanium,” among other
materials. (Manderson 59) This relative stagnation has a simple cause: current pure-physical
implants (implants that operate purely mechanically, with no electrical or computer components)
are operating at or near the peak of present day materials science, able to match the natural
structures they aim to replace in many regards. (eg Oscar Pistorius, who runs at the Olympic
level on two artificial lower legs made of carbon fiber. [Hilvoorde and Landeweerd 2222])
At present, in addition to the historical prostheses described above, a wide variety of
experimental prosthetics exist. These devices, though often speculative and neither rigorously
tested nor widely deployed, represent the cutting edge of human augmentation, serving as a
snapshot of the height present-day technology. While the field of hearing implants, meant to
grant the ability to perceive sound to those with malfunctioning or absent auditory physiology, is
long established, progress towards the restoration of sight has been more limited, with, as yet,
no commercial products. (Hearing implants have been commercialized and widely available
since the mid-80s.) (Rosahl 289) Now, however, artificial vision technology is beginning to bear
fruit. Microprocessors, attached to light sensors or cameras and implanted directly into the eye,
in contact with nerve cells, have been used to deliver a “train of stimuli…to…the optic nerve, ”
providing some measure of sight. (Rosahl 290) Such devices are limited by the need for
external power supplies, since it is impossible to fit a power source into the eye along with the
interface chip, and offer very limited resolution: “40x40 elements,” presumably equivalent to
computer pixels, and a field of view of “about 12 degrees.” (Rosahl 291) The technical
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specifications are not awe-inspiring, but what matters most is the precedent set: successful
integration between a computerized sensory system and a highly complicated set of nerves
(each eye contains 130 million photoreceptors [Rosahl 290]), a first step towards direct mindmachine interfaces.
In terms of direct mind-machine communication, the experiments of Kevin Warwick offer
a fascinating glimpse at the possibilities of present technology. In 2001, he had a tiny
microelectrode array “implanted into [his] nervous system via the median nerve in [his] arm”
(Warwick caption on page 2 of picture insert), so as to record the neural signals associated with
movement of his fingers and miscellaneous sense data sent along the nerve. (Warwick 131-2)
The implant worked successfully, and Warwick was able to make a number of highly impressive
demonstrations of the technology. By connecting the chip in his arm to a computer programmed
to interpret the produced by his nerves when he opened or closed his hand, he made a robotic
hand precisely follow his actions, opening and closing with his flesh and blood appendage.
(Warwick 233) Using similar ‘translation’ programs, he was also able to control a number of
other simple electronic systems, such as a “Lego [sic] robot” (Warwick 235) and a virtual coffee
maker (Warwick 234), as well as drive a powered wheelchair. (Warwick 288-9) Critically, though,
this implant was not a one-way device, merely reading Warwick’s nerve impulses; it also sent
artificial, computer-generated, signals into his nerves. After connecting the implant to force
sensors, Warwick was able to “feel the force [of an artificial hand on an object]…on [his] own
hand.” (288) After his wife was fitted with a similar implant, she and Warwick were able to send
pulses to each other over the Internet, with near-perfect accuracy, performing “the first direct
nervous system to nervous system link-up.” (Warwick 282-7)
The most tantalizing present-day experiments, though, from a transhumanist perspective,
are those that push human sensory perception beyond its present limits and into new fields. To
be a cyborg, a trans-human, is to be one “whose capabilities are extended beyond normal limits”
(Chris Butlin, quoted on Warwick 61) Thus, as one’s physical abilities expand, as the legs of
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Oscar Pistorius promise, so too must one’s senses. Warwick achieved results here as well.
After a set of ultrasonic antennae were attached to his implant, he acquired a form of
echolocation and was able to ‘see’ the distance to nearby objects while blindfolded. (Warwick
262-4) He “had gained a new sense.” (Warwick 264) While this was an impressive
demonstration of the brain’s plasticity and ability to process novel sensory data, an important
prerequisite for all such future endeavors, for if the brain were limited to interpreting only natural
senses the prospects for future augmentation would be rather limited, it essentially merely
replicated a specific aspect of sight. The data were sourced and presented to the brain in a
novel manner, but they themselves (the knowledge of how far away a certain object was) could
have been obtained by any person with functional eyes. Thus, the augmentation described by
Norton provides a more powerful demonstration of transhumanist potential: the acquisition, via a
simple implant, of a sense possessed by no living human. He, along with several others, had a
“rare earth magnet implanted in his finger” and thereby gained the ability to sense
electromagnetic fields. (Norton) Interestingly, although the magnet transmits sensation to the
implantee via vibrations, the implantee perceives magnetic fields as “tingles” and “pure
stimulation.” (Norton) In addition to their transhumanist potential, both these bold experiments,
unfortunately, also demonstrate a key drawback of present-day implant technology: the
tendency of the implant itself to fail while inside the body. By the end of the experiment, only
three of the one hundred contacts between Warwick’s implant and his nerves remained
functional (Warwick 256) and Norton’s implanted magnet “shattered into pieces.” (Norton)
By extrapolating from the above and general technological trends, it is possible to gain
an some idea of what the next few years may bring. For ‘dumb’ prosthetics the current slow
pace of advance will likely continue, with incremental advances in engineering and materials
leading to incremental, but consistent, improvements in performance. (Manderson 60)
Computerized prosthetics, on the other hand, will likely prove much more exciting, their
development driven by the powerful advances already taking place in general computing and
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the integrative work of scientists such Professor Warwick. By tapping the extant nerves and
using computers (built into the arm) to process the signals into commands to be sent to motors
and provide force-feedback into those same nerves, a prosthetic arm presently in development
can achieve a level of functionality almost equal to that of a natural arm. (Williams TK add to
bibliography) With time and further research providing better understanding of the nerves
involved and better signal processing, it seems not unreasonable to predict that, in the near
future, similar computer-aided prosthetics will grant amputees and those born without limbs
artificial organs (near-)equal to, or possibly even superior to, organic limbs in power, control,
and perception. Critically, it is the application of computer power to what were formerly purely
mechanical systems that is leading, and will lead to this great leap in prosthetic technology. A
so-called ‘computer revolution’ has already transformed countless sectors of human life, from
business to entertainment to air travel; prosthetics are simply the next area of revolution.
The truly earthshaking advances, though, will come from using emerging technology to
push the capabilities of the human body into realms completely inaccessible to pure humans,
those not cybernetically enhanced. The electromagnetic sense that Norton acquired in a backalley procedure will likely be just the first of many such non-standard senses granted by
augmentations. In a similar vein to Warwick’s experiments with an ultrasonic ranger (Warwick
262-4), it is simple to imagine connecting a wide variety of sensory equipment, from sensors for
any segment of the electromagnetic spectrum, allowing vision beyond the so-called ‘visible
range’ of frequencies, to more esoteric devices, such as gravimeters or ammeters, directly to
the nervous system. The cyborg of the near future will thus be vastly more aware of the world
around themselves than any contemporary human, thanks to their greatly enhanced sensory
perception. These augmentations, as well, as the advanced prostheses described above, are all
minor examples of what may well be the holy grail of transhuman augmentation: the mindmachine interface, wherein an artificial device is connected directly to the brain itself. Nervecontrolled prostheses and additional senses are only the beginning of what such an interface
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would allow, such as direct access from the brain to all the general-purpose computational
power of any number of silicon chips, allowing for, among other things, intuitive control of
complicated mechanical systems. Such fusions have already been performed upon some insect
species (Warwick 109), although, given the great complexity of the human brain, it is likely that
the equivalents of such interfaces for humans are a long way away.
Of course, all these advanced devices will require power, often in copious quantities.
While many current prostheses and implants run on internal batteries or external power supplies,
these technologies have significant issues. Internal batteries, such as those used in implanted
defibrillators and other such devices, inevitably run dry and can only be replaced through
surgery, an impractical and invasive solution. (Halperin 13) While external batteries present no
such difficulties, their weight and size often cause significant encumbrance. See, for example,
the oversized ‘gauntlet’ that Warwick used to power and communicate with his implant.
(Warwick picture section) Furthermore, by requiring connections that pierce the skin, so as to
supply power to the implant, such external power sources leave the implantee continually
vulnerable to infection. (Fessenden 43) Thus, future augmentations are likely to rely on other
sources of power than batteries. Since external generators are obviously inferior in this regard,
the best solution may be to make the devices power themselves, as a recent development in
fuel cell technology promises. Using glucose, which is readily available in the body, as fuel,
these new biofuel cells produce a continuous supply of power from within the body, and have
already been successfully “integrated” into basic electronic circuitry. (Fessenden 43) While such
fuel cells are probably “10 years” away from commercialization, due to insufficient power
production and issues with bio-reactivity, implants equipped with improved versions of such fuel
cells could function completely autonomously within the body, powering everything from mindmachine interfaces in the spinal column to artificial muscle fibers. (Fessenden 43)
While advanced implants and computerized prostheses have great potential and offer
huge improvements over traditional, ‘dumb’ prostheses, they also come with additional risks.
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With a ‘dumb,’ non-computerized prostheses, failure only occurs when the physical structure of
the device itself is compromised, eg, a wooden leg breaking under extreme stress, or the hinge
on a simple prosthetic arm locking due to insufficient lubrication. While such failures are, clearly,
not without risk to the bearer, because they are due to the physical properties of the prosthesis,
they are both immediately obvious and easily diagnosable. Most importantly, to deliberately
induce such a failure, to maliciously compromise a ‘dumb’ prosthesis, is not easily accomplished
without obvious brute force and direct physical access to the prosthesis in question, thus
making such attacks generally unproductive and infeasible. Unfortunately, computerized
prostheses lack several, if not all of these advantages, rendering their bearers significantly more
vulnerable. In an extreme example, Halperin et al., a multidisciplinary team of researchers,
managed, with no prior knowledge of the interior workings of the device, to reverse engineer the
wireless signals used to control an implantable defibrillator and gain near complete control over
the device. (1-2) Critically, they gained the ability to remotely activate the defibrillator, potentially
killing the implantee, and to artificially “[deplete] the battery life and [threaten the] availability” of
the device, leaving the bearer vulnerable to future incidents requiring defibrillation. (Halperin 2)
This attack is performed remotely, via a radio transmitter, though only out to a range of “several
centimeters.” (Halperin 2) As this example demonstrates, a computerized implant, capable of
communicating with external devices for worthy reasons (such as the ability to “modify [the
device’s] setting without surgery” [Halperin 1]), is made vulnerable by those very advantages; a
‘dumb’ defibrillator, for all its disadvantages, could not be so compromised. Most devastatingly,
for a security standpoint, this attack can be performed without alerting the implantee, since the
sabotage is performed over a wireless connection. While, as Halperin et al. note, no such attack
has yet been carried out (2), that it is so easily and subtly performed is quite worrying.
When considered in the light of the more thoroughly integrated systems imagined by
Professor Warwick, such an attack becomes terrifying. Even as far back as the late 90’s, it was
possible to control the body by computer, as shown by the work of an artist known as Stelarc,
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who used a computer to guide his movements by means of electrodes placed on his skin to
stimulate his muscles. (Warwick 70) Even now we can already perform the sort of integration
that will render this manner of indirect control obsolete: the construction of a mind-machine
interfaces, with computers connected “directly into the brain,” have been built for cockroaches,
leeches, and even rats. (Warwick 109) In humans, implants that directly stimulate muscles on
command (from either an external source or from other implants that react to specific muscle
motion) to, for example, restore the ability to grip to paraplegics, are already in use. (Warwick
117) Computer systems are already fundamentally involved in these implants, and as they grow
more complicated and more powerful, as the implants for paraplegics restore the ability not just
to generically grip, say, but to grip with individual fingers with specific amounts of force,
computers will only become more entangled in the process. From a security standpoint, this is
potentially catastrophic, for, the more powerful the system, the more devastating the successful
attack. External subversion of muscle control, or even, via hijacking of whatever direct mindmachine interfaces may exist, one’s very thoughts, would be a brutal crime. As the example of
the defibrillator demonstrates, every beneficial function can be subverted and put to evil ends;
the greater the benefit, the greater the potential evil. The opportunities for crime, for hostage
taking and extortion and torture, are incredible, and thus the threat faced is immense.
Fortunately, though, the bearers of these future prosthetics will not be completely at the
mercy of the world; security is indeed possible, though not without tradeoffs. As Halperin et al.
discuss in their paper, wireless attacks such as theirs can be thwarted by several simple
modifications to the implant. The implant can be made to “audibly alert” (Halperin 10) the patient
when an attempt is made to communicate with the device, allowing the implantee to notice and
respond to attacks. Additionally, a “cryptographically strong [communication] protocol” (Halperin
10) can be used, preventing an adversary from easily reverse engineering the codes needed to
sabotage the implant. Unfortunately, such security measures cannot be made arbitrarily strong,
as they must not “hinder treatment in an emergency situation” or otherwise prevent the device
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from functioning properly. (Halperin 10) Also, while such relatively passive measures as these
may (‘may’ is the operative word here, as Halperin notes that very little research has been done
in this area [10-11]) be sufficient to protect such a relatively simple implant as the defibrillator
under discussion, it seems clear, from the history of computer systems thus far, that as implants
advance in complexity, the security measures necessary to provide even nominal protection will
increase dramatically. By analogy to general computer history, an ‘arms race,’ a constant
evolutionary battle of adaptation and counter-adaptation between security programs and threats,
seems likely. However, prosthetics and augmentations complex enough to require such
complex security procedures are likely many years away from widespread availability and use
(see above) and so it is hard to speculate beyond these generalities.
In addition to the practical issues of safety and security discussed above, the advance of
implant technology also raises new ethical considerations. Historically, prosthetics have been
firmly placed in the realm of the disabled. Their purpose was to provide (some semblance of)
normal bodily functionality to those whose bodies were lacking in some regard. The prosthesis
served to simulate some aspect of the healthy and whole body, to undo some physiological
compromise. Most importantly for the following discussion, this placement has meant that the
unaugmented human, an average person with no disabilities, was always superior in ability to
the average prosthesis-endowed human, for prostheses were inferior in ability to that which they
attempted to replace. Put simply, a prosthetic heart, for all its life-saving power, is strictly inferior
to the natural article, and so on for other organs. In the present day, though, we appear to have
come to an inflection point; prosthetics are beginning to equal, and possibly surpass, natural
organs. Indicative of this change is the runner Oscar Pistorius, who, despite running on two
artificial lower legs, is firmly competitive with “elite [Olympic-level] athletes on ‘natural legs.’”
(Hilvoorde and Landeweerd 2222) As Hilvoorde and Landeweerd discuss, this toppling of the
previous hierarchy of natural over prosthetic (while Pistorius is ‘merely’ competitive with and not
strictly superior to his unaugmented competitors, he is easily seen as a harbinger of what further
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technological advances will bring) “blur[s] the distinction between able and disabled” (2224) and,
ironically, may even invert it. When prosthetics are superior to flesh and bone, a new,
“increased inequality” will arise, “between those that are technologically ‘enhanced’ and those
that are not.” (Hilvoorde and Landeweerd 2224) Those formerly regarded as ‘abled’ will take the
place of the ‘disabled,’ as the augmented, formerly ‘disabled’ and otherwise, tower above them
in capability.
While this raises obvious issues around the concept of ‘fair competition’ in sports
(Hilvoorde and Landeweerd 2223-6), this is a matter of grave concern for ethics in general, for it
has the potential to increase social stratification along socioeconomic lines. Key to John Rawls’
conception of ‘justice’ is the notion that, all personal capabilities being equal, two individuals
should have equal opportunity, regardless of the circumstances of their birth and family. In
general, this is the Western framework used to evaluate items effecting societal outcomes; that
which is good is that which promotes Rawlsian justice. (Hilvoorde and Landeweerd 2223) Since
advanced prosthetics are, as high tech works of specialized engineering, expensive items, the
inability of the economic lower class to afford enhancements easily available to the upper class
will suppress them even further and increase the anti-Rawlsian inequality of outcomes between
rich and poor. Warwick takes this prophecy of widening to the extreme, arguing that “cyborgs
will split from humans. Those who remain as mere humans…[will] become a sub-species…the
chimpanzees of the future.” (4) Given that human domination over less able animals is marked
by “contempt” and the often callous “disposal” of lives (Warwick 2), such a scenario does not
bode well for the unaugmented, and should give pause to transhumanists. Even if all of
humanity will eventually be so augmented, and equality thus regained on a higher plane of
ability, unless the transition is literally instantaneous, provisions will need to be made to protect
those who, due to choice or contingency, remain fully natural in an augmenting society. It would
be a deeply ironic disaster if transhumanism, in bootstrapping humanity past the stifling confines
of the flesh, only deepened the devastating inequalities of the present world.
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The transhumanist project, as mentioned above, is at an inflection point. Technology
formerly only dreamt of is now making its way from the brains of futurists into the research labs
and factories of the world, soon to spread to wide availability. From carbon-fiber legs to hardwired nerve interfaces, the possibilities for human expansion grow almost daily. Cyborgs, some
argue, already walk among us, as our omnipresent computer devices function as mental
augmentations, prosthetic brains; soon, however, this will unarguably be the case, as implants
and replacement organs become more common and, eventually, commoditized. All this,
however, is not set in stone, and herein lies the choice to be made. How will this brave new
world of implants be regulated and governed? Will this technology be available to all, subsidized
or on loan, or restricted only to the military and/or the rich? How will humanity (or will it, even)
act to prevent a Brave New World, in which modification of the human body becomes the
means to tyranny and oppression? Finally what does this project mean for ‘humanity’ itself?
How much augmentation turns a human into a transhuman? Whatever choices and discoveries
are made, however these questions are answered, may the transhumans of the future look
kindly upon us, we who lived in this era of their birth.
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Works Cited:
Fessenden, Marissa. "Sugar-Powered Pacemakers." Scientific American December 2012: 43.
Halperin, Daniel et al. “Pacemakers and Implantable Cardiac Defibrillators: Software Radio
Attacks and Zero-Power Defenses.” IEEE Symposium on Security and Privacy, May 2008.
Medical Device Security Center. Web. 25 Nov. 2012. http://www.secure-medicine.org/icdstudy/icd-study.pdf
Lorenzi, Rossella. “Ancient Egyptian Fake Toes Earliest Prosthetics.” Discovery News 2 Oct.
2012: n.pag. news.discovery.com. Web. 14 Dec. 2012.
http://news.discovery.com/history/ancient-egypt-wooden-toes-prosthetics-121002.html
Manderson, Lenore. Surface Tensions: Surgery, Bodily Boundaries, and the Social Self. Walnut
Creek: Left Coast Press, 2011.
Norton, Quinn. "A Sixth Sense for a Wired World." Wired 7 June 2006: n.pag. Wired.com. Web.
25 Nov. 2012. http://www.wired.com/gadgets/mods/news/2006/06/71087?currentPage=all
Rosahl, Steffen K. "Vanishing Senses—Restoration Of Sensory Functions By Electronic
Implants." Poiesis & Praxis 2.4 (2004): 285-295. Academic Search Premier. Web. 25 Nov. 2012.
Van Hilvoorde, Ivo, and Laurens Landeweerd. "Enhancing Disabilities: Transhumanism Under
The Veil Of Inclusion?." Disability & Rehabilitation 32.26 (2010): 2222-2227. Academic Search
Premier. Web. 25 Nov. 2012.
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Warwick, Kevin. I, Cyborg. London: Century, 2002
Williams, Adams. “Mind-controlled permanently-attached prosthetic arm could revolutionize
prosthetics.” Gizmag 29 Nov. 2012: n.pag. Gizmag.com. Web. 14 Dec. 2012.
http://www.gizmag.com/thought-controlled-prosthetic-arm/25216/
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