Perceptions under Memory’s Contractions. §13, Matter and Memory. Bergson

Corry Shores

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Perceptions under Memory’s Contractions

Henri Bergson

Matter and Memory

Matière et mémoire

Chapter I

“Of the Selection of Images For Conscious Presentation. What our Body Means and Does.”

§13

‘What then becomes of Consciousness? Preliminary Hints.’

Previously Bergson explained that perceptions usually lead to actions. In lower life-forms, a perception automatically brings-about a reaction. In humans, there is more cerebral deliberation. But we can expect that eventually a reaction will result.

We relate to things that we perceive. But because a human does not react immediately to them, there is a "zone of indetermination which surrounds its activity." (23a)

Bergson now wonders why this more-or-less distant relation to objects takes the form of conscious perception. We receive movements through our nervous systems. Our brains will delay reaction. During this time, the motions are active in our brains. When we do act, the movements are sent back through the nerves to cause us our bodies to act. But all these motions are involved in our indeterminate action and not necessarily in representation. Because our actions are indeterminate, our perceptions are necessarily variable relations between us and “the more or less distant influence of the objects” that interest us. (24a) Bergson asks why such a perception is consciousness, and why it seems as if our consciousness originates in “the internal movements” of the brain.

Bergson will first simplify the conditions for conscious perception.

All perceptions are “full of memories.” Our senses give us data right now in the present. These sense data “mingle with a thousand details out of our past experience.” The memories usually take the place of the perceptions we are actually then experiencing. What we retain from them are “only a few hints” that we use “merely as ‘signs’ that recall to us former images.” (24bc) Perceptions come so rapidly that we are left with these traces.

Bergson will now consider a perception that is not so laden with memory. It would be “confined to the present and absorbed, to the exclusion of all else, in the task of moulding itself upon the external object.” (24d) Philosophers so far have not recognized such an “impersonal perception.” They never distinguished it from what “memory adds to or subtracts from it, they have taken perception as a whole for a kind of interior and subjective vision, which would then differ from memory only by its greater intensity.” (25a.b)

This first hypothesis leads to yet another. A perception might be very brief. Yet it “always occupies a certain duration, and involves consequently an effort of memory which prolongs one into another a plurality of moments.” (25bc) In this way, memory contracts the different moments of perception.

As we shall endeavor to show, even the ‘subjectivity’ of sensible qualities consists above all else in a kind of contraction of the real, effected by our memory. In short, memory in these two forms, covering as it does with a cloak of recollections a core of immediate perception, and also contracting a number of external moments into a single internal moment, constitutes the principal share of individual consciousness in perception, the subjective side of the knowledge of things. (25c, emphasis mine)

Même, comme nous essaierons de le montrer, la « subjectivité » des qualités sensibles consiste surtout dans une espèce de contraction du réel, opérée par notre mémoire. Bref, la mémoire sous ces deux formes, en tant qu’elle recouvre d’une nappe de souvenirs un fond de perception immédiate et en tant aussi qu’elle contracte une multiplicité de moments, constitue le principal apport de la conscience individuelle dans la perception, le côte subjectif de notre connaissance des choses. (21bc, emphasis mine)

Bergson will proceed now to discuss perception in its purity, and not as it is “enlarged by memories and offers a certain breadth of duration.” (26a) Bergson says that by “pure perception,”

“I mean a perception which exists in theory rather than in fact and would be possessed by a being placed where I am, living as I live, but absorbed in the present and capable, by giving up every form of memory, of obtaining a vision of matter both immediate and instantaneous. (26b, emphasis mine)

une perception qui existe en droit plutôt qu’en fait, celle qu’aurait un être placé où je suis, vivant comme je vis, mais absorbé dans le présent, et capable, par l’élimination de la mémoire sous toutes ses formes, d’obtenir de la matière une vision à la fois immédiate et instantanée. (21-22, emphasis mine)

Bergson will now proceed to discuss conscious perception.

Images from the English translation.

Images from the original French.

Bergson, Henri. Matière et mémoire: Essai sur la relation du corps à l'esprit. Ed. Félix Alcan. Paris: Ancienne Librairie Germer Bailliere et Cie, 1903. Available online at: http://www.archive.org/details/matireetmmoiree01berggoog

Bergson, Henri. Matter and Memory. Transl. Nancy Margaret Paul & W. Scott Palmer. Mineola, New York: Dover Publications, Inc., 2004; originally published by George Allen & Co., Ltd., London, 1912. Available online at: http://www.archive.org/details/mattermemory00berg

Spinoza's Foci for Deleuze's Contraction

by Corry Shores
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Spinoza's Foci

for Deleuze's Contraction

There is already extensive research and commentary on Spinoza’s philosophy. Somehow, it missed what might be one of the most important keys for unlocking his ideas. Spinoza’s day job was lens grinding. And so as well he was an expert in optics. We might keep this in mind and return anew to Spinoza’s fundamental concepts. In the very least we see a potent explanatory metaphor. We might consider for example our minds as lenses that could be polished to attain greater rational clarity. But the possibility remains that perhaps there is a more comprehensive way to view Spinoza’s philosophy: we might reexamine it under the light of his optical theories and craftsmanship. To do so would require extensive research, analysis, and commentary on these topics. Fortunately, all this original work has already been done. Kvond at Frames /sing indexes his many various treatments here. It is really incredible work, and it is changing the way I read and comprehend Spinoza.

And more recently kvond has begun work with analog and digital, relating it to Spinoza’s infinite. [See this entry and this one. Also see this entry on the topic of the infinite]. Kvond writes of Spinoza’s infinite:

The Infinite is Unbroken. And following this, modifications of the Infinite (how Spinoza defines the modes) do not break that unbroken state. (kvond, Spinoza on the Infinite, the Unbound: Part I)

We might call something analog if it has the property of being continuous, and digital if it is made of discrete parts. Because we may go on dividing some extending thing over and over and never come to ultimate divisions, it would seem to be continuous and analog. We might also think of it in terms of magnification. We look at a part of something under a magnifying glass. Then we grind a lens of a greater power, and see that there is still more parts within that one. And so on forever. No matter how powerful the lens, we can always (metaphorically) craft a stronger one, and see a smaller part of something. These divisions or magnifications that we make are really products of the imagination, imposed upon a substance that is fundamentally indivisible. Kvond expresses this another way when he writes:

One can see that there is a certain “faculative disorder” in the (digital) peak tracing of diagrammic representations, but, following Spinoza, these can only be analogical, which is to say continual, conjoinings. If Spinoza’s treatment of the infinite which disjoins the imaginarily discrete (mathematical) infinity from the real, expressive causal infinity, tells us anything, it is that diagrammic dis-organization and re-organization are imaginary processes which ever seek a continuity in the body itself, the body an infinite expression of magnitudes which press nestled upon each other. But unlike Deleuze’s pursuit of the chaotic elements (and this may only be an aesthetic difference), looking with the Intellect, as Spinoza would, is seeing-through these connections, not as bound, but as continually out-flowing and unitary. In this sense the ordering of numbers is a pale, imaginary imitation of the density of continuity in all things, a mechanism for our continual re-orientation. (kvond, Analog and Digital Intellect: Threshold Intensity, or Either/Or)

My aim here will be to explore Deleuze’s interpretation of Spinoza’s infinity, while building from some of kvond’s work on Spinoza’s optics and lens craftsmanship. However, my broader aim is to see if Deleuze’s version of Spinoza’s infinity is of a “contracted” series of discrete changes. I will begin first with kvond’s remarkable entries on Spinoza’s 39^th and 40^th letters. To really get a grasp of them in all their detail, see these entries by kvond:

Deciphering Spinoza’s Optical Letters

Some Observations on Spinoza’s Sight

A Diversity of Sight: Descartes vs. Spinoza

Spinoza: Letter 40 and Letter 39

Descartes’ Dioptrics 7th Discourse and Spinoza’s Letters 39 and 40

A Conflation of Spinoza Diagrams

Spherical Aberration: Descartes’ Solution

An origin of Spinoza’s “cones of rays” explanation, Letter 40

Spinoza’s Blunder and the Spherical Lens

Spinoza’s Letter 39: Descartes’ Silence

I would like to make use us of the circle diagram to help interpret Spinoza’s other circle diagram in his Letter on the Infinite.

The circle diagram depicts a circular lens.

Really, it is the ideal eyeball. The straight lines are rays of light.

To understand its properties, we make certain presumptions. We assume

1) this is a perfect circle

2) there is an exterior band of rays all parallel to line AB, and the spherical lens bends them so that they all converge at single point B.

Not every spherical lens will do this. But we might by some means construct one that could [see kvond's correction of the translation so that it is correctly formulated as a hypothetical, here and here]. Now, supposing that the spherical lens is perfectly circular, we can conclude that the same refraction-phenomenon will happen if a band of parallel rays shines from another axis, at a different angle. These are parallel to DC.

The light refracts the same way because “the circle, being everywhere the same, has everywhere the same properties.” (Spinoza, 215) No matter what the axis’s angle may be, the rays will converge on the opposite side of the lens. And they can be any of an infinite array of different axes; kvond writes

for Spinoza the Ideal Eye is one that in using the properties of a circle is able to focus rays parallel to a variety of axes (in fact, an infinity of axes). (Some Observations on Spinoza’s Sight)

Descartes has a diagram that might allow us to elaborate on how the circle is everywhere the same.

Descartes writes:

the surfaces of transparent bodies which are curved deflect the rays passing through each of their points in the same way as would the flat surfaces that we can imagine touching these bodies at the same points.

[and he continues:

As, for example, the refraction of the rays AB, AC, AD, which, coming from the flame A, fall on the curved surface of the crystal ball BCD, must be considered in the same way as if AB fell on the flat surface EBF, and AC on GCH, and AD on IDK, and so with the others. From which you can see that these rays can be variously gathered or dispersed, according as they fall on surfaces which are differently curved. And it is time that I start to describe the structure of the eye to you, in order that you will be able to understand how the rays which enter within it are so disposed there as to cause the sensation of sight. (Descartes, Optics, Second Discourse, p.83b.d)]

What I note is that Descartes seems to draw tangents along the circle as being those surfaces which refract the light. We can also think of tangents this way: we spin a ball on a rope. If we cut the string at any time, the ball flies off at a ninety degree angle to the string. This is also the tangent to the circle.

In fact, Spinoza says that the definition for a circle, like all other definitions, should be genetic, in that the definition produces the thing defined. This is the first requirement for definitions:

Rule I:

[96] (1) The definition must contain the proximate cause of the thing. [96] (2) So for example, we should define the circle as the figure traced by the end of a moving line rotating around its other endpoint, which is fixed in place, like how we draw a circle with a compass. (Spinoza, Improvement of the Understanding)

In fact, as kvond points out, Spinoza’s work on a lathe could have continually reminded him of a circle formed by motion:

It is no secret that Spinoza had great love for the circle as a diagramed exemplar of the relationship between the modes and Substance (Ethics 2p8s, pictured below), but also as an ideal of vision and the actions of optical focus (Letter 39 to Jelles, March 3rd 1667). Here, for hours on end Spinoza would stare determinitively as a rotating circular form which remained both fixed (stable in its ratio), and changing, expressing in both the consummation of the vectors of the room’s actions. (Spinoza’s “Spring Pole” Lathe: Experience to Metaphysics and Back)

(image obtained gratefully from kvond’s entry:

Spinoza’s “Spring Pole” Lathe: Experience to Metaphysics and Back)

So one way to conceive a circle is in terms of it being made of points all ‘tending’ 90 degrees from their respective radius. That means each point tends a different direction. But they all tend the same degree away from the center point. So in this sense, the circle is everywhere tending to change direction at the same "rate."

Now we will turn to Spinoza’s diagram from his 12^th letter, the “Letter on Infinity.”

[It is more thoroughly explained in this entry.]

The inner circle does not share the same center with the larger one. Let’s consider first if it did. The smaller circle would be tending to change direction continuously at the same rate. The larger one will as well. Because they both change at the same rate relative to the same center point, the distances between them will remain the same. But if the center circle is off-set, then the two will no longer be continuously coordinated. Rather, they will be continuously divergent. So the circles remain everywhere the same, but the differences between them are everywhere different.

Because the differing of the inter-mediate space is continuous, there will be infinitely many differences between them. Extensive space fills that continuously differing gap. We may divide that space up over-and-over again, and never arrive upon a finite set of small parts.

This is where we might find grounds for Deleuze’s mixture of analog and digital, or continuous and discrete, by means of a contraction rather than a flowing continuum.

there are last terms: the simplest bodies‚ for Spinoza. These are the ultimate terms, these are the terms which are last, which you can no longer divide. But, these terms are infinitely small. They are the infinitely small, and this is the actual infinite. (Deleuze, Cours Vincennes 10/03/1981)

Because they are infinitely small, these terms do not have extensive measure. They are "vanishing" quantities. In the case of our diagram, they would be like the infinite series of limits found throughout the middle space. Look at these diagrams to see that as we add more rectangles under the curve, they become narrower each time.

(Image from Edwards & Penney Calculus)

Imagine if we did something similar with Spinoza’s off-set circles. As the number of rectangle-like forms nears infinity, the spaces between will approach zero. We want to consider them once they are smaller than any finite extent, but still not yet zero. So they are vanishing, but not yet entirely vanished. There will be an infinity of limits in the circle’s middle space. But that does not mean it has somehow become like a solid of limits. One limit does not overlap with another to make a flowing continuum. They are still discretely different, even though their number is infinite. [I need a mathematician's help to determine if this is correct, and what is the better way to express it. The relevant calculus entries are this one and this one.]

So we may infinitely divide the space between the circles, and arrive upon these discrete inextensive simple bodies, which are limits. The change of tendency from one to another can have a certain degree of intensity. Deleuze writes:

An intensive quantity is inseparable from a threshold, that is an intensive quantity is fundamentally, in itself, already a difference. The intensive quantity is made of differences. (Deleuze, Cours Vincennes 20-01-1981)

We may consider any one limit and determine its tendency toward changing, by using differential calculus. So to go from one discrete limit to the one on its border there is not an extensive difference, but a difference of degree (of change in tendency). We might consider the sum of all the differential tendencies. If the circles were concentric, then there would not be a series of such differences. Each circle’s tendencies to change would continuously correspond to the other’s. But because Spinoza’s circles are offset, there is a sort of sum of internal differentiation.

We would consider such a collection of intensive differences an ‘individual.’

an individual is not a simple body, an individual, whatever it is, and however small it is, an individual has an infinity of simple bodies, an individual has an infinite collection of the infinitely small. (Deleuze, Cours Vincennes 10/03/1981)

So the region between the circles is infinitely divisible into an infinity of infinitely-small discrete “spaces” (although, none extend in space; however, they do not equal zero either). We may consider any one of them alone, and in that sense they are discrete. But, there is no extensive space between them either. So in that way they are continuous. But they are not continuous in a flowing way where each part overlaps with its neighbors. Rather, the discrete parts have no extensive space between them, so they are contracted together. However, the changes from one to the next can have a certain intensity. When later discussing Bergson’s duration, we will look at this contraction that creates an intense series of discrete consciousness states.

Spinoza. The Letters. Transl Samuel Shirley. Cambridge: Hackett Publishing Company, Inc., 1995.

Edwards & Penney. Calculus. New Jersey: Prentice Hall, 2002.

Posthumanism and Pixels, Condensed Version

by Corry Shores
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[The following is a condensed version of a previous text. There you will find proper citation. I thank Professor Ulrich Melle, Professor Aziz Zambak, and my Father Ebbie V. Shores for their contributions to this research. And may I thank kvond at Frames/ sing for opening new directions for the philosophy of Analog & Digital. Later we will examine his developments and ways to integrate these ideas with Spinoza's thinking.]

Corry Shores

Do Posthumanists Dream of Pixilated Sheep?

Bostrom and Sandberg's Brain Emulation,

Examined and Critiqued

Enhancement technologies may someday give us capacities far beyond what we dream humanly possible. We could become post-human. Nick Bostrom & Anders Sandberg suggest that we might survive our body's death by living as a computer simulation. They issued a report from a conference where experts in all relevant fields collaborated to determine the path to "whole brain emulation." This technology will in the very least be an effective research tool for the neurosciences. It could even aid philosophical research too. Their "roadmap" defends certain philosophical assumptions required for this technology's success. So by determining the reasons why it succeeds or fails, we can obtain empirical data for philosophical debates regarding our mind and selfhood. I have chosen four issues to discuss: emergentism, analog vs. digital, chance, and personal identity.

Brain emulation succeeds if a computer program replicates human neural functioning. Yet for the authors, its success increases when it perfectly replicates one specific person’s brain. She might then survive her body’s death by living as the simulation.

This prospect has posthumanist proponents. Their view presupposes certain traits of human consciousness and selfhood. Hans Moravec for example thinks our personal identities exist independently to our bodies. According to his pattern-identity theory of selfhood, we are no more than the patterns and the processes found in our brains and bodies. William Bainbridge explains that we are neither man nor machine. We are just the dynamic patterns of information that can be realized in a wide variety of materials. Hence our personal patterns might be found in this body or in that computer. Either way we are the same person.

To emulate someone’s neural patterns, we first scan a particular brain to obtain precise detail of its structures and their interactions. Using this data, we program a simulation that will behave essentially the same as the original brain. Now first consider a gnat’s wild flight pattern. It seems irrational and random. But the motion of a whole swarm is smooth, controlled, and intelligent, as though the whole group of gnats has a mind of its own. To simulate the swarm, perhaps we will not need to understand how the whole swarm thinks. We instead just learn the way one gnat behaves and interacts with other ones. When we combine thousands of these simulated gnats, the swarm’s collective intelligence should thereby appear. Whole brain emulation presupposes this principle. The simulation will mimic the human brain’s functioning on the cellular level. Then automatically, higher-and-higher orders of organization should spontaneously arise. Finally human consciousness might emerge at the highest level of organization.

Early in this technology's development, we should only expect simpler brain states, like wakefulness and sleep. But in its ultimate form, whole brain emulation would enable us to make back-up copies of our minds. Then we might somehow survive our body’s death.

According to Bostrom & Sandberg, whole brain emulation should replicate all the original brain’s relevant properties so to produce a 1-to-1 model of the brain’s functioning. In this sense, the brain and its emulation are black boxes. We feed each one on its own the same sequence of stimuli. If they both respond with the same sequence of reactions, then the two separate machines are functionally equivalent. In this way, the same mind could be realized in two physically different systems. Hilary Putnam claims that electronic computers can be functionally equivalent to mechanical ones and even to humans using pencil and paper. Their insides may differ drastically, but their outward behaviors are identical.

There are various levels of emulation success. The highest ones are the most philosophically interesting.

When the technology achieves individual brain emulation, Bostrom & Sandberg write, it produces emergent activity characteristic of one particular brain. With further success, we would emulate someone’s personal identity. Perhaps somehow it would be numerically the same person. But at least it would continue-on as that person even after her body dies. We achieve such a simulation when it becomes rationally self-concerned for the brain it emulates.

Minds emerge from the brain’s pattern of physical dynamics. If you replicate this pattern-dynamic in some other physical medium, the same mental phenomena should likewise emerge. One mind would then be realized in a multiplicity of different physical embodiments. So whole brain emulation’s success would provide evidence for the theory of multiple realizability.

According to emergentist theories, all reality is made-up of a single kind of stuff. But its parts aggregate and assemble into dynamic organizational patterns. The higher levels exhibit properties not found in the lower ones. But, there can be no higher order without lower ones underlying it.

Consider the H2O molecule. It does not itself bear the properties of liquidity, wetness, and transparency. However, a large enough aggregate of water molecules will exhibit these properties.

In our brains, no one single neuron is conscious. Yet, your minds emerge from the complex dynamic pattern of all our neurons communicating and computing in parallel. Roger Sperry offers compelling evidence. There are "split brain" patients whose right and left brain hemispheres are disconnected from one another. Nonetheless, they maintain unified consciousness.

William Hasker offers the analogy of magnetic fields, which are distinct from the magnets producing them. The iron atoms themselves need to be organized in alignment in order for a magnetic field to emerge on a higher scale. In a similar way, the particular organization of the brain’s neurons generates a field of ‘consciousness.’ This emergent consciousness-field permeates and haloes our brain-matter, occupying its space and traveling along with it.

Not everyone agrees that the mind emerges from the brain. Todd Feinberg is one example. Now in fact, he does think that consciousness results from the complex interaction of many layers of neural organization. However, he argues that consciousness does not get squirted-out from neural activity and thereby obtain a life of its own. Instead, the layers of neural activity are all mutually interdependent and simultaneously cooperative. Consider for example when we recognize our grandmother. One layer of neurons transmits information about the whole visual field. Another layer picks-out lines. Another one, shapes. Finally the information arrives at the grandmother cell, which only fires when it is she that we see. But this does not make the grandmother cell emergently higher. Rather, all the neural layers of organization must work together simultaneously to achieve this recognition. The brain is a vast network of interconnected circuits. So we cannot say that any layer of organization emerges over and above the others.

Feinberg’s objection may prove problematic for whole brain emulation. Bostrom & Sandberg explicitly state that we only need to simulate the lower levels of activity.

But if Feinberg’s holistic theory is correct, we cannot only emulate the lower levels and expect the rest to spontaneously emerge. For, we need already to understand the higher-levels in order to program the lower ones. So, whole brain emulation’s emergentist assumptions might not express the actual way that consciousness appears.

Notice how in the recent past, many digital technologies have replaced analog ones. It would seem that these two sorts of quantity-representation reside in contrary worlds: the continuous versus the discrete. An abacus is digital. It computes one discrete value or another, but it is blind to the values between its lowest digit-places. When we count to two on our fingers, meaningless empty space spans between our digits. So spreading our fingers further apart does not change their numerical value. Slide-rules, however, are analog. One ruler slides against another continuously. So it may calculate any possible real number along the continuum. It could potentially compute and display irrational numbers like pi or the golden ratio. However, a digital computer would never cease calculating into lower digit places. For, there can be no final figure when rendering irrational numbers into digits. But if you move the slide rule from three to four, you will for one instant display pi. Analog is dense. Between any two values is already a third one, and lying between those are yet even more, and so on infinitely. On account of this infinite divisibility, analog can compute and display an infinity of different values found within a finite range. But like the gaps between our fingers, digital at some point will be blind to a middle value, no matter how precise it is. So, because analog computers can deal with an infinity of values, they have more computing potential for certain applications.

Our emulated brain will receive simulated sense-signals. Does it matter if they are digital signals rather than analog? Many audiophiles swear by the unsurpassable superiority of analog. It might be less precise, but it always flows like natural sound waves. Digital, even as it becomes more accurate, still sounds to them artificial or cartoon-like. In other words, there might be a qualitative difference to how we experience analog and digital stimuli, even though it might take a person with extra sensitivities to bring this difference to our explicit awareness.

And if the continuous and discrete are so fundamentally different, then maybe a brain computing in analog would experience a qualitatively different feel of consciousness than if the brain were instead computing in digital. Perhaps digital emulations might even produce a mental awareness quite foreign to what humans normally experience.

Bostrom’s & Sandberg’s brain emulation exclusively uses digital computation. But, they acknowledge the argument that analog and digital are qualitatively different. And, they admit that implementing analog in brain emulation could present profound difficulties. Yet, there is no need to worry, they say.

They pose what is called “the argument from noise.” Analog devices always take some physical form. It is unavoidable that interferences and irregularities, called noise, will make the analog device imprecise. So analog might be capable of taking-on an infinite range of variations. However, it will never be absolutely accurate, because noise always causes it to veer-off slightly from where it should be. Yet digital has its own inaccuracies. It is always missing variables between its discrete values. Nonetheless, digital is improving. Little-by-little it is coming to handle more variables. It is filling in the gaps. Digital will never be completely dense like analog. Values will always slip through its fingers. And analog will always miss its mark. But soon the distance between digital’s smallest fingers will equal the distance that analog veers-away from its proper course. Digital’s blindness would then match analog’s sloppiness. So, we only need to wait for digital technology to improve enough that it can compute the same values with equivalent precision. Both will be equally inaccurate, but for fundamentally different reasons.

But perhaps the argument from noise reduces the analog/digital distinction to a quantitative difference rather than a qualitative one. And analog is so prevalent in neural functioning that we should not so quickly brush it off.

Note first that our nervous system’s electrical signals are discrete pulses, like Morse code. In that sense they are digital. However, the frequency of the pulses can vary continuously. As well, there are many other neural quantities that are analog in this way.

Fred Dretske argues that our memories store information in analog. We might consider an event that occurred somewhere within a 15 minute time-span. But later, we also might search our memory for finer details to indicate more specifically when that event occurred. Because we can always further refine our remembered determinations, it could very well be that our brains record data in analog form.

But suppose anyway that the argument from noise is correct, and that we can dismiss analog’s computational superiority. Would there still be some reason to implement analog technology?

Recent research on neural-network learning supplies an answer. Analog noise interference is significantly more effective than digital at aiding adaptation. Being "wrong" allows neurons to explore new possibilities for computational values and connections. This enables us to learn and adapt to a chaotically changing environment. Using digitally-simulated neural noise might be inadequate. Analog is better. For, it affords our neurons an infinite array of alternate configurations. Hence, in response to Bostrom’s & Sandberg’s argument from noise, I propose this argument for noise. Analog’s inaccuracies take the form of continuous variation. In my view, this is precisely what makes it necessary for whole brain emulation.

Neural noise can result from external interferences like magnetic fields. Or internal random fluctuations might make the signals unpredictable. In both cases, chance & chaos reign our brains. And in fact, these random, indeterminate, and probabilistic events assist our brain’s computations. It implements noise to keep us adjusted to the world’s changes and uncertainties.

Some also theorize that noise is essential to the human brain’s creativity. Johnson-Laird claims that creative mental processes are never predictable. On this basis, he suggests a way to make computers think creatively. We make them alter their own functioning by submitting their programs to artificially-generated random variations. According to Daniel Dennett, such indeterminism is precisely what endows us with what we call free will. Likewise, Bostrom & Sandberg suggest we introduce random noise into our simulation by using pseudo-random number generators. They are not truly random, because eventually the pattern will repeat. But if it takes a very long time before the repetitions appear, then probably it would be sufficiently close to real randomness. It would be a major obstacle, Bostrom & Sandberg write, if artificial noise is not random enough for whole brain emulation.

Research suggests that we may characterize our neural irregularities as pink noise, or what is called 1/f noise. Benoit Mandelbrot classifies 1/f noise as what he terms “wild randomness.” This sort of random might not be so easily simulated. The stock market for example is wildly random. In such natural systems, astronomically improbable fluctuations occur frequently. There is no way to predict when they will appear or how drastic they will be.

For this reason, he considers wild variation to be a state of indeterminism that is qualitatively different than the usual mild variations we encounter at the casino. For, there is infinite variance in the distributions of wild randomness. Anything can happen at any time. He says, “the fluctuation from one value to the next is limitless and frightening.” And this is the wildness of our brains.

Paul Shepard considers our minds to be wild in an even more literal sense: we are wild animals. He distinguishes tameness from domestication. Cows are domesticated. They have been bred to suit our needs. And now their genes would probably not prepare them to live in the wild without human protections. But the human species has merely been tamed by culture and not domesticated like cows. Genetically, we are still the same wild creatures who hunted the Pleistocene savannas. So to emulate the human brain is to simulate the workings not of a rational machine, but of a wild animal. He writes, “The savage mind is ours! ... as a species we have in us the call of the wild.”

But let’s suppose that the brain’s wild randomness can be adequately simulated. Will brain emulation still attain its fullest success of perfectly replicating a specific person’s own identity? Bostrom & Sandberg recognize that neural noise will prevent precise one-to-one emulation. However, they think that the noise will not prevent the simulation from producing meaningful brain states. But to pursue further the personal identity question, let’s imagine that we want to emulate a certain casino slot machine. A relevant property is its unpredictability. So, do we want the emulation and the original to both give consistently the same outcomes? That would happen if we precisely duplicate of all the original’s relevant physical properties. But what about its essential unpredictability? The physically-accurate emulation could predict in advance all the original’s forthcoming read-outs. Or instead, would a more faithful copy of the original produce its own distinct set of unpredictable outcomes? Then we would be replicating the original’s most important relevant property of being governed by chance.

The problem is that the brain’s 1/f noise is wildly random. So suppose we emulate some person’s brain perfectly. And suppose further that the original person and her emulation have an identity merger where each one somehow mistakes themselves for the other. Yet, if both minds are subject to wild variations, then their consciousness and identity might come to differ more than just slightly. They could veer-off wildly. Perhaps our very effort to emulate a specific human brain results in our producing an entirely different mind altogether.

Whether this technology succeeds or fails, it still can advance a number of philosophical debates. It could tell us if our minds emerge from our brains; if the philosophy of artificial intelligence should take analog more seriously. We might learn whether our brain’s randomness is responsible for creativity, adaptation, and free choice; or, if this randomness is the reason our personal identities cannot be duplicated. The only failure, as I see it, is if we neglect this technology’s philosophical potential.

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