Philosopher Thomas Nagel famously characterised subjective
experience as “something that it is like to be…” and suggested that for a bat,
for instance, there must be something that it is like to be a bat [1]. Nagel
also argued that, since we humans differ so much from bats in the way we
perceive and interact with the world, then it is impossible for us to know what
it is like for a bat to be a bat. I am fascinated, intrigued and perplexed by
Nagel’s ideas in equal measure. And, since I think about robots, I have assumed
that if a robot were ever to have conscious subjective experience then there must
be something that it is like to be a robot that – even though we had designed that robot – we could not know.
But I now believe it may eventually be just possible for a
human to experience something approaching what it is like to be a robot. To do
this would require two advances: one in immersive robot tele-operation, the
other in the neuroscience of body self-image manipulation.
Consider first, tele-operation. Tele-operated robots are,
basically, remotely controlled robots. They are the unloved poor relations of
intelligent autonomous robots. Neither intelligent nor autonomous, they are
nevertheless successful and important first wave robots; think of remotely
operated vehicles (ROVs) engaged in undersea exploration or oil-well repair and
maintenance. Think also of off-world exploration: the Mars rovers are hugely
successful; the rock-stars of tele-operated robots.
Roboticists are good at appropriating technologies or
devices developed for other applications and putting them to good use in robots:
examples are WiFi, mobile phone cameras and the Microsoft Kinnect. With the
high profile launch of the Oculus Rift headset, and their acquisition by
Facebook, and with competing devices from Sony and others, there are encouraging
signs that immersive Virtual Reality (VR) is on the verge of becoming a
practical, workable proposition. Of course VR’s big market is video games – but
VR can and, I believe, will revolutionise tele-operated robotics.
Imagine a tele-operated robot with a camera linked to the
remote operator’s VR headset, so that every time she moves her head to look in
a new direction the robot’s camera moves in sync; so she sees and hears what
the robot sees and hears in immersive high definition stereo. Of course the
reality experienced by the robot’s operator is real, not virtual, but the head
mounted VR technology is the key to making it work. Add haptic gloves for control
and the robot’s operator has an intuitive and immersive interface with the
robot.
Now consider body self-image modification. Using mirror
visual feedback researchers have discovered that it is surprisingly easy to
(temporarily) modify anyone’s body self-image. In the famous rubber hand illusion
a small screen is positioned to hide a subject’s real hand. A rubber hand
is positioned where her hand could be, in full view, then a researcher
simultaneously strokes both the real and rubber hands with a soft brush. Within
a minute or so she begins to feel the rubber hand is hers, and flinches when
the researcher suddenly tries to hit it with a hammer.
Remarkably H.H. Ehrsson and his colleagues extended the
technique to the whole body, in a study called ‘If I Were You: Perceptual
Illusion of Body Swapping’ [2]. Here the human subject wears a headset and
looks down at his own body. However, what he actually sees is a mannequin,
viewed from a camera mounted on the mannequin’s head. Simultaneous tactile and
visual feedback triggers the illusion that the mannequin’s body is his own. It
seems to me that if this technique works for mannequins then it should also
work for robots. Of course it would need to be developed to the point that
elaborate illusions involving mirrors, cameras and other researchers providing
tactile feedback are not needed.
Now imagine such a body self-image modification technology combined with fully immersive robot
tele-operation based on advanced Virtual Reality technology. I think this might
lead to the robot's human operator experiencing the illusion of being one with
the robot, complete with a body self-image that matches the robot's possibly
non-humanoid body. This experience may be so convincing that the robot's
operator experiences, at least partially, something like what it is to be a
robot. Philosophers of mind would disagree - and rightly so; after all, this
robot has no independent subjective experience of the world, so there is no
something that it is like to be. The human operator could not experience what
it is like to think like a robot, but she
could experience what it is like to sense and act in the world like a robot.
The experience may be so compelling that humans become
addicted to the feeling of being a robot fish, or robot dragon or some other
fantasy creature, that they prefer this to the quotidian experience of their
own bodies.
[1] Nagel, Thomas. What is it like to be a bat?, Mortal
Questions, Cambridge University Press, 1979.
[2] Petkova VI, Ehrsson HH (2008) If I Were You: Perceptual
Illusion of Body Swapping. PLoS ONE 3(12): e3832. doi:10.1371/journal.pone.0003832
