Welcome to the Machine, Part 4: Kurzweil's nano neural nets

Previously in series: The Ethics of Simulated Beings, Descartes's Malicious Demon and The Simulation Argument.

As previously noted in this series, our entire world may be simulated. For all we know we're sitting on a powerful supercomputer somewhere, the mere playthings of posthuman intelligences.

But this is not the only possibility. There's another way that this kind of fully immersive 'reality' could be realized -- one that doesn't require the simulation of an entire world. Indeed, it's quite possible that your life is not what it seems -- that what you think of as reality is actually an illusion of the senses. You could be experiencing a completely immersive and totally convincing virtual reality right now and you don't even know it.

How could such a thing be possible? Nanotechnology, of course.

The nano neural net

In his book, The Singularity is Near, futurist Ray Kurzweil describes how a nanotechnology powered neural network could give rise to the ultimate virtual reality experience. By suffusing the brain with specialized nanobots, he speculates that we will someday be able to override reality and replace it with an experience that's completely fabricated. And all without the use of a single brain jack.

Here's how:

First, we have to remember that all sensory data we experience is converted into electrical signals that the brain can process. The brain does a very good job of this, and we in turn experience these inputs as subjective awareness (namely through consciousness and feelings of qualia); our perception of reality is therefore nothing more than the brain's interpretation of incoming sensory information.

Now imagine that you could stop this sensory data at the conversion point and replace it with something else.

That's where the nano neural net comes in. According to Kurzweil, nanbots would park themselves near every interneuronal connection coming in from our senses (sight, hearing, touch, balance, etc.). They would then work to 1) halt the incoming sensory signals (not difficult -- we already know how to use "neuron transistors" that can detect and suppress neuronal firing) and 2) replace these inputs with the signals required to support a believable virtual reality environment (a bit more challenging).

As Kurzweil notes, "The brain does not experience the body directly." As far as the conscious self is concerned, the sensory data would completely override the feelings generated by the real environment. The brain would experience the synthetic signals just as it would the real ones.

Generating synthetic experiences

Clearly, the second step -- generating new sensory signals -- is radically more complicated than the first (not to mention, of course, the difficulty of creating nanobots that can actually work within the brain itself!). Creating and transmitting credible artificial sensory data will be no easy feat. We will need to completely reverse engineer the brain so that we can map all requisite sensory interactions. We'll also need a fairly sophisticated AI to generate the stream of sensory data that's needed to create a succession of believable life experiences.

But assuming we can get a nano neural net to work, the sky's the limit in terms of how we could use it. Kurzweil notes,

You could decide to cause your muscles and limbs to move as you normally would, but the nanobots would intercept these interneuronal signals, suppress your real limbs from moving, and instead cause your virtual limbs to move, appropriately adjusting your vestibular system and providing the appropriate movement and reorientation in the virtual environment.

From there we will create virtual reality experiences as real or surreal as our imaginations allow. We'll be able to choose different bodies, reside in all sorts of environments and interact with our fellow neural netters. It'll be an entirely new realm of existence. This new world, with all its richness and possibility, may eventually supplant our very own.

And in some cases, we may even wish to suppress and alter our memories such that we won't know who we really are and that we're actually living in a VR environment...

A topic I will explore in more detail in my next post.

Welcome to the Machine, Part 3: The Simulation Argument

Previously in series: The Ethics of Simulated Beings and Descartes's Malicious Demon.

No longer relegated to the domain of science fiction or the ravings of street corner lunatics, the "simulation argument" has increasingly become a serious theory amongst academics, one that has been best articulated by philosopher Nick Bostrom.

In his seminal paper "Are You Living in a Computer Simulation?" Bostrom applies the assumption of substrate-independence, the idea that mental states can reside on multiple types of physical substrates, including the digital realm. He speculates that a computer running a suitable program could in fact be conscious. He also argues that future civilizations will very likely be able to pull off this trick and that many of the technologies required to do so have already been shown to be compatible with known physical laws and engineering constraints.

Harnessing computational power

Similar to futurists Ray Kurzweil and Vernor Vinge, Bostrom believes that enormous amounts of computing power will be available in the future. Moore's Law, which describes an eerily regular exponential increase in processing power, is showing no signs of waning, nor is it obvious that it ever will.

To build these kinds of simulations, a posthuman civilization would have to embark upon computational megaprojects. As Bostrom notes, determining an upper bound for computational power is difficult, but a number of thinkers have given it a shot. Eric Drexler has outlined a design for a system the size of a sugar cube that would perform 10^21 instructions per second. Robert Bradbury gives a rough estimate of 10^42 operations per second for a computer with a mass on order of a large planet. Seth Lloyd calculates an upper bound for a 1 kg computer of 5*10^50 logical operations per second carried out on ~10^31 bits – this would likely be done on a quantum computer or computers built of out of nuclear matter or plasma [check out this article and this article for more information].

More radically, John Barrow has demonstrated that, under a very strict set of cosmological conditions, indefinite information processing (pdf) can exist in an ever-expanding universe.

At any rate, this extreme level of computational power is astounding and it defies human comprehension. It’s like imagining a universe within a universe -- and that's precisely be how it may be used.

Worlds within worlds

"Let us suppose for a moment that these predictions are correct," writes Bostrom. "One thing that later generations might do with their super-powerful computers is run detailed simulations of their forebears or of people like their forebears." And because their computers would be so powerful, notes Bostrom, they could run many such simulations.

This observation, that there could be many simulations, led Bostrom to a fascinating conclusion. It's conceivable, he argues, that the vast majority of minds like ours do not belong to the original species but rather to people simulated by the advanced descendants of the original species. If this were the case, "we would be rational to think that we are likely among the simulated minds rather than among the original biological ones."

Moreover, there is also the possibility that simulated civilizations may become posthuman themselves. Bostrom writes,

They may then run their own ancestor-simulations on powerful computers they build in their simulated universe. Such computers would be “virtual machines”, a familiar concept in computer science. (Java script web-applets, for instance, run on a virtual machine – a simulated computer – inside your desktop.) Virtual machines can be stacked: it’s possible to simulate a machine simulating another machine, and so on, in arbitrarily many steps of iteration...we would have to suspect that the posthumans running our simulation are themselves simulated beings; and their creators, in turn, may also be simulated beings.

Given this matrioshkan possibility, the number of "real" minds across all existence should be vastly outnumbered by simulated minds. The suggestion that we're not living in a simulation must therefore address the apparent gross improbabilities in question.

Again, all this presupposes, of course, that civilizations are capable of surviving to the point where it's possible to run simulations of forebears and that our descendants desire to do so. But as noted above, there doesn't seem to be any reason to preclude such a technological feat.

Next: Kurzweil's nano neural nets.

Welcome to the Machine, Part 2: Descartes's malicious demon

Previously in series: "Welcome to the Machine, Part 1: The ethics of simulated beings."

A little over 350 years ago, philosopher René Descartes was struck by a rather disturbing thought. Is it possible, he wondered, that what we think of as reality is nothing more than an elaborate hoax?

Descartes, who was writing in his Meditations on First Philosophy, conceived of this possibility while formulating his principle of methodological skepticism. He was trying to find a fundamental set of principles that he believed could be known without a modicum of doubt. He ended up concluding that any idea that can be doubted should be doubted, giving rise to what is now known as Cartesian skepticism.

Consequently, Descartes doubted a lot, including the efficacy of our senses to convey reality as it truly is. He used the example of dreaming to illuminate the point. When dreaming, our senses perceive things that seem real, but do not actually exist. "Thus what I thought I had seen with my eyes," he wrote, "I actually grasped solely with the faculty of judgment, which is in my mind." From this observation Descartes concluded that we cannot rely solely on our senses, as they may not be telling us what is necessarily true.

Taking this line of inquiry further and applying it to the "real" world, Descartes thought it conceivable that the reality we take for granted may actually be a complex hallucination orchestrated by some kind of powerful intelligence, what he referred to as a "malicious demon."

"It is at least possible that there is an all-powerful evil demon who is deceiving me, such that he causes me to have false beliefs, including the belief that there is a table in front of me and the belief that two plus three equals five," wrote Descartes. The all-powerful evil demon, he argued, could feed us whatever experiences he chooses. "I shall think that the sky, the air, the earth, colors, shapes, sounds and all external things are merely the delusions of dreams which he has devised to ensnare my judgment."

Undeniably, Descartes was on to something, but because of his place in time and history, he was unable to formulate sound technical explanations to describe how such a hoax could come about, save reference to supernatural intervention.

More recently, however, philosophers and scientists have come up with novel theoretical scenarios describing how such a hoax could in fact be perpetuated. Thirty years ago philosophers envisioned vats with floating brains that were fed sensory experiences. Today they envision powerful haptic and neural interfaces, virtual realities and sophisticated supercomputers running elaborate simulations.

Indeed, given the radical potential for supercomputers and our growing understanding of mental state functionalism (i.e. cognitive computationalism), we are coming to realize that even consciousness is subject to analog-to-digital conversion. And while we no longer speak of demons, we now consider the work of superintelligences running simulations of mind-boggling complexity and power.

Tomorrow: The Simulation Argument.

Welcome to the Machine, Part 1: The ethics of simulated beings

Without a doubt some of my favorite video games of all time have been those that involve simulations, including SimCity and The Sims.

When I play these games I fancy myself a demigod, managing and manipulating the slew of variables made available to me; with the click of a mouse I can alter the environment and adjust the nature of the simulated inhabitants themselves.

There's no question that these games are becoming evermore realistic and sophisticated. A few years ago, for example, a plug-in was developed for The Sims allowing the virtual inhabitants to entertain themselves by playing none other than SimCity itself. When I first heard about this I was struck with the vision of Russian Matrioshka nesting dolls, but instead of dolls I saw simulations within simulations within simulations.


And then I remembered good old Copernicus and his principle of mediocrity: We should never assume that our own particular place in space and time is somehow special or unique. Thinking of the simulation Matrioshka, I reflected on the possibility that we might be Sims ourselves: Why should we assume that we are at the primary level of reality?

Indeed, considering the radical potential for computing power in the decades to come, we may be residing somewhere deep within the Matrioshka.

Consequently, we are all faced with a myriad of existential, philosophical and ethical questions. If we are merely simulants, what does it mean to be alive? Are our lives somehow lessened or even devoid of meaning? Should we interact with the world and our fellow simulants differently than before we knew we were living in a simulation? How are we to devise moral and ethical codes of conduct?

In other words, how are we to live?

Well, there's no reason to get too excited over this. It's a bit of speculative metaphysics that doesn't really change anything -- assuming we are in a simulation, we should live virtually the same way as if we were living in the "real" world.

That is unless, of course, those running the simulation expect something from us. Which means we need to figure out what it is exactly we're supposed to do...

Tomorrow - Part 2: Descarte's 'Malicious Demons.'

BNT interviews Jason Silva on radical life extension

Ian MacKenzie of Brave New Traveler talks to Jason Silva, a 26-year old film maker and outspoken immortalist.

MacKenzie asks, "You quote The Immortalist in your film - how did you come across it and why does it resonate with you?" Silver responds:

After watching the brilliant film Vanilla Sky, I spent hours on the internet researching Cryonic Suspension.

This idea that we could preserve ourselves until the technology was there to repair the wear and tear of aging and eventual pathology.

Like the lucid dream that was presented in the film, if we removed finitude from the human condition, life could be transformed into an eternal now- no more existential anxiety.

I started reading about Ray Kurzweil and Aubrey de Grey, brilliant thinkers who professed that through scientific engineering we would someday conquer death.

The philosophical implications and motivations behind this, however, were best described by Alan Harrington’s masterpiece, “The Immortalist”- a manifesto of sorts that dared to challenge our cosmic inferiority complex and complacent attitude about our “inevitable” demise, and instead challenged us to engineer (with SCIENCE) an ageless and divine state of being.

This is where science would satisfy the yearnings of existential man, who for too long was suffering as a consequence of being aware of his mortality.

Here's Silva's short film, "The Immortalists":

Latest podcast posted: 2008.04.08

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This episode:

Eight tips to dramatically improve your chances of living forever

Exploring George's existential angst