- Artificial consciousness
Artificial consciousness (AC), also known as machine consciousness (MC) or synthetic consciousness, is a field related to
artificial intelligenceand cognitive roboticswhose aim is to define that which would have to be synthesized were consciousness to be found in an engineered artifact. Harv|Aleksander|1995 Neurosciencehypothesizes that consciousness is generated by the interoperation of various parts of the brain, called the neural correlates of consciousness or NCC. Proponents of AC believe computers can emulate this interoperation, which is not yet fully understood.
The nature of consciousness
naïve realismand direct realism, humans perceive directly while brains perform processing. According to indirect realismand dualism, brains contain data obtained by processing but what people perceive is a mental model or state appearing to overlay physical things as a result of projective geometry (such as the point observation in René Descartes' dualism). Which of these approaches to consciousness is correct is fiercely debated.
Direct perception problematically requires a new physical theory allowing conscious experience to supervene directly on the world outside the brain. But if people perceive indirectly through a world model in the brain, then a new physical phenomenon, other than the endless further flow of data, would be needed to explain how the model becomes experience.
If people perceive directly,
self-awarenessis difficult to explain because one of the principal reasons for proposing direct perception is to avoid Ryle's regresswhere internal processing recurses infinitely. Direct perception also demands that one cannot really be aware of dreams, imagination, mental images or any inner life because these would involve recursion.
Self awareness is less problematic for entities that perceive indirectly because, by definition, they are perceiving their own state. However, as mentioned above, proponents of indirect perception must suggest some phenomenon, either physical or dualist to prevent Ryle's regress. If people perceive indirectly then self awareness might result from the extension of experience in time described by
Immanuel Kant, William Jamesand Descartes. Unfortunately this extension in time may not be consistent with our current understanding of physics.
Information processing and consciousness
Information processingconsists of encoding a state, such as the geometry of an image, on a carrier such as a stream of electrons, and then submitting this encoded state to a series of transformations specified by a set of instructions called a program. In principle the carrier could be anything, even steel balls or onions, and the machine that implements the instructions need not be electronic, it could be mechanical or fluidic.
Digital computers implement information processing. From the earliest days of digital computers people have suggested that these devices may one day be conscious. One of the earliest workers to consider this idea seriously was
If technologists were limited to the use of the principles of digital computing when creating a conscious entity they would have the problems associated with the philosophy of
strong AI. The most serious problem is John Searle's controversial Chinese roomargument which seeks to demonstrate that the act of computation does not necessarily produce a conscious experience of understanding.
Searle's objection does not convince everybody. Direct perception proponents maintain that 'meaning' is only to be found in objects of perception. Many philosophers have abandoned "intrinsic" meaning for
Wittgensteinian approaches, conceptual role semantics, and so on. The objection is also countered by the concept of " strong emergentism" which proposes some unspecified new physical phenomenon arises from processor complexity.
The debate about whether a machine could be conscious under any circumstances is usually described as the conflict between
physicalismand dualism. Dualists believe that there is something non-physical about consciousness whilst physicalists hold that all things are physical.
Consciousness in digital computers
There are various aspects of consciousness generally deemed necessary for a machine to be artificially conscious. A variety of functions in which consciousness plays a role were suggested by
Bernard Baars. The aim of AC is to define whether and how these and other aspects of consciousness can be synthesized in an engineered artefact such as digital computer. This list is not exhaustive; there are many others not covered.
Awarenesscould be one required aspect, but there are many problems with the exact definition of "awareness". The results of the experiments of neuroscanning on monkeys suggest that a process, not a state or object activates neurons [http://www-inst.eecs.berkeley.edu/~cs182/readings/ns/article.html] . For such reaction there must be created a model of the process based on the information received through the senses in such a way demands a lot of flexibility, and is also useful for making predictions.
Learning is also considered necessary for AC. An interesting article about learning is Implicit learning and consciousness [http://srsc.ulb.ac.be/axcWWW/papers/pdf/01-AXCLJ.pdf] by
Axel Cleeremans, University of Brussels and Luis Jiménez, University of Santiago, where learning is defined as “a set of philogenetically ["sic"] advanced adaptation processes that critically depend on an evolved sensitivity to subjective experience so as to enable agents to afford flexible control over their actions in complex, unpredictable environments”
The ability to predict (or anticipate) foreseeable events is considered important for AC by
Igor Aleksander. The emergentist multiple drafts principle proposed by Daniel Dennettin " Consciousness Explained" may be useful for prediction: It involves the evaluation and selection of the most appropriate "draft" to fit the current environment.
Anticipation is a characteristic that could possibly be used to make a machine appear conscious. An artificially conscious machine should be able to anticipate events correctly in order to be ready to respond to them when they occur. The implication here is that the machine needs real-time components, making it possible to demonstrate that it possesses artificial consciousness in the present and not just in the past. In order to do this, the machine being tested must operate coherently in an unpredictable environment, to simulate the real world.
Subjective experience or
qualiais widely considered to be "the" hard problem of consciousness. Indeed, it is held to pose a challenge to physicalism, let alone computationalism.
chools of thought
There are several commonly stated views regarding the plausibility and capability of AC, and the likelihood that AC will ever be real consciousness. Some say the thermostat is really conscious, but they do not claim the thermostat is capable of an [http://www.newscientist.com/news/news.jsp?id=ns99994845 appreciation of music] . In an interview [http://www.users.bigpond.com/nedthefish/chalmers1.htm] Chalmers called his statement that thermostat is conscious "very speculative" and he is not a keen proponent of
panpsychism. Harv|Chalmers|1996|p=298 Interpretations like that are possible because of deliberately loose definitions, but tend to be too restrictive to have any significant intellectual value.
Artificial Consciousness must not be as genuine as
Strong AI, it must be as objective as the scientific methoddemands and capable of achieving known objectively observable abilities of consciousness, except subjective experience, which by Thomas Nagelcannot be objectively observed.
; Nihilistic view
It is impossible to test if anything is conscious. To ask a thermometer to appreciate music is like asking a human to think in five dimensions. It is unnecessary for humans to think in five dimensions, as much as it is irrelevant for thermometers to understand music. According to the nihilistic view, consciousness is just a word attributed to things that appear to make their own choices and perhaps things that are too complex for our mind to comprehend. Things seem to be conscious, but that is just because our ethical attitudes require a conscious-not conscious distinction, or because of our
empathywith other entities. Consciousness is an optional perspective or social construct. (Compare with Daniel Dennett's " intentional stance", and eliminativism).
Artificial consciousness as a field of study
Artificial consciousness includes
researchaiming to create and study artificially conscious systems in order to understand corresponding natural mechanisms.
The term "artificial consciousness" was used by several scientists including Professor Igor Aleksander, a faculty member at the
Imperial Collegein London, England, who stated in his book "Impossible Minds" that the principles for creating a conscious machine already existed but that it would take forty years to train such a machine to understand language. Understanding a language does not mean understand the language you are using. Dogs may understand up to 200 words, but may not be able to demonstrate to everyone that they can do so.
At this time analog holographic sentience modeled after humans is more likely to be a successful approach.Or|date=September 2007
AC research has moved beyond the realm of philosophy; several serious attempts are underway to instill consciousness in machines. four of these are described below.
Franklin’s Intelligent Distribution Agent
Stan Franklin(1995, 2003) defines an autonomous agentas possessing functional consciousness when it is capable of several of the functions of consciousness as identified by Bernard Baars’ Global Workspace TheoryHarv|Baars|1988, Harv|Baars|1997. His brain child IDA (Intelligent Distribution Agent) is a software implementation of GWT, which makes it functionally conscious by definition. IDA’s task is to negotiate new assignments for sailors in the US Navy after they end a tour of duty, by matching each individual’s skills and preferences with the Navy’s needs. IDA interacts with Navy databases and communicates with the sailors via natural language email dialog while obeying a large set of Navy policies. The IDA computational model was developed during 1996-2001 at Stan Franklin’s "Conscious" Software Research Group at the [http://www.memphis.edu/ University of Memphis] . It "consists of approximately a quarter-million lines of Java code, and almost completely consumes the resources of a 2001 high-end workstation." It relies heavily on "codelets", which are "special purpose, relatively independent, mini-agent [s] typically implemented as a small piece of code running as a separate thread." In IDA’s top-down architecture, high-level cognitive functions are explicitly modeled; see Harvtxt|Franklin|1995 and Harvtxt|Franklin|2003 for details. While IDA is functionally conscious by definition, Franklin does “not attribute phenomenal consciousness to his own 'conscious' software agent, IDA, in spite of her many human-like behaviours. This in spite of watching several US Navy detailers repeatedly nodding their heads saying 'Yes, that’s how I do it' while watching IDA’s internal and external actions as she performs her task."
Ron Sun's cognitive architecture CLARION
CLARION posits a two-level representation that explains the distinction between conscious and unconscious mental processes.
CLARION has been successful in accounting for a variety of psychological data. A number of well-known skill learning tasks have been simulated using CLARION that span the spectrum ranging from simple reactive skills to complex cognitive skills. The tasks include serial reaction time (SRT) tasks, artificial grammar learning (AGL) tasks, process control (PC) tasks, the categorical inference (CI) task, the alphabetical arithmetic (AA) task, and the Tower of Hanoi (TOH) task Harv|Sun|2002. Among them, SRT, AGL, and PC are typical implicit learning tasks, very much relevant to the issue of consciousness as they operationalized the notion of consciousness in the context of psychological experiments .
The simulations using CLARION provide detailed, process-based interpretations of experimental data related to consciousness, in the context of a broadly scoped cognitive architecture and a unified theory of cognition. Such interpretations are important for a precise, process-based understanding of consciousness and other aspects of cognition, leading up to better appreciations of the role of consciousness in human cognition Harv|Sun|1999. CLARION also makes quantitative and qualitative predictions regarding cognition in the areas of memory, learning, motivation, meta-cognition, and so on. These predictions either have been experimentally tested already or are in the process of being tested.
Haikonen’s cognitive architecture
Pentti Harvtxt|Haikonen|2003 considers classical rule-based computing inadequate for achieving AC: "the brain is definitely not a computer. Thinking is not an execution of programmed strings of commands. The brain is not a numerical calculator either. We do not think by numbers." Rather than trying to achieve
mindand consciousnessby identifying and implementing their underlying computational rules, Haikonen proposes "a special cognitive architectureto reproduce the processesof perception, inner imagery, inner speech, pain, pleasure, emotionsand the cognitivefunctions behind these. This bottom-up architecture would produce higher-level functions by the power of the elementary processing units, the artificial neurons, without algorithmsor programs". Haikonen believes that, when implemented with sufficient complexity, this architecture will develop consciousness, which he considers to be "a style and way of operation, characterized by distributed signal representation, perception process, cross-modality reporting and availability for retrospection." Haikonen is not alone in this process view of consciousness, or the view that AC will spontaneously emerge in autonomous agents that have a suitable neuro-inspired architecture of complexity; these are shared by many, e.g. Harvtxt|Freeman|1999 and Harvtxt|Cotterill|2003. A low-complexity implementation of the architecture proposed by Harvtxt|Haikonen|2004 was reportedly not capable of AC, but did exhibit emotions as expected.
Takeno's self-awareness research
Self-awareness in robots is being investigated by Junichi Takeno [http://robonable.typepad.jp/robot/2_/index.html] at
Meiji Universityin Japan. Takeno is asserting that he has developed a robot capable of discriminating between a self-image in a mirror and any other having an identical image to it [http://www.rs.cs.meiji.ac.jp/Takeno_Archive/DiscoveryNewsAwareRobot211205.pdf] [http://www.mimed.mw.tum.de/06-12-18_MIMED_LUETH-002918.PDF] , and this claim has been already reviewed. Harv|Takeno|Inaba|Suzuki|2005
Testing for artificial consciousness
Unless artificial consciousness can be proven formally, judgments of the success of any implementation will depend on observation.
Turing testis a proposal for identifying machine intelligence as determined by a machine's ability to interact with a person. In the Turing test one has to guess whether the entity one is interacting with is a machine or a human, without any visual clues — the conversation is usually held over a terminal. An artificially conscious entity could only pass an equivalent test when it had itself passed beyond the imaginations of observers and entered into a meaningful relationship with them, and perhaps with fellow instances of itself.
A cat or dog would not be able to pass this test. It is highly likely that consciousness is not an exclusive property of humans. Therefore, it is possible that a machine could be conscious and not be able to pass the Turing test. However, it would probably be a
serendipitousoccurrence because most efforts in artificial intelligenceare focussed on intelligenceand cognitionrather than consciousness.
As mentioned above, the
Chinese roomargument seeks to debunk the validity of the Turing Test by showing that a machine can pass the test and yet not have human-style semantics.
Since there is an enormous range of human behaviours, all of which are deemed to be conscious, it is difficult to lay down all the criteria by which to determine whether a machine manifests consciousness.
Furthermore, many would argue that no test of "behaviour" can prove or disprove the existence of consciousness because a conscious entity can have
dreams, qualiaand other features of an inner life. This point is made forcibly by those who stress the subjective nature of conscious experience such as Thomas Nagelwho, in his essay, " [http://members.aol.com/NeoNoetics/Nagel_Bat.html What is it like to be a bat?] ", argues that subjective experiencecannot be reduced, because it cannot be objectively observed, but subjective experience is not in contradiction with physicalism.
Although objective criteria are being proposed as prerequisites for testing the consciousness of a machine, the failure of any particular test would not disprove consciousness. Ultimately it will only be possible to assess whether a machine is conscious when a universally accepted understanding of consciousness is available.
Another test of AC, in the opinion of some, should include a demonstration that machine can learn the ability to filter out certain stimuli in its environment, to focus on certain stimuli, and to show attention toward its environment in general. The mechanisms that govern how human attention is driven are not yet fully understood by scientists. This absence of knowledge could be exploited by engineers of AC; since we don't understand attentiveness in humans, we do not have specific and known criteria to measure it in machines. Since unconsciousness in humans equates to total inattentiveness, an AC should have outputs that indicate where its attention is focused at any one time, at least during the aforementioned test. By Antonio Chella from University of Palermo [https://bandura.sbs.arizona.edu/login/consciousness/report_web_detail.aspx?abs=315] "The mapping between the conceptual and the linguistic areas gives the interpretation of linguistic symbols in terms of conceptual structures. It is achieved through a focus of attention mechanism implemented by means of suitable recurrent neural networks with internal states. A sequential attentive mechanism is hypothesized that suitably scans the conceptual representation and, according to the hypotheses generated on the basis of previous knowledge, it predicts and detects the interesting events occurring in the scene. Hence, starting from the incoming information, such a mechanism generates expectations and it makes contexts in which hypotheses may be verified and, if necessary, adjusted."
Another test for consciousness, commonly proposed by some futurists such as
transhumanists, is to hook the human brain up to a machine in an integral way. Presently, brain-computer interfacesare fairly primitive, and only allow for information to be channeled in to or out of the human brain, but not both ways due to the massive computational complexity this would require of the computer and bandwidth restrictions. However, as BCIs continue to progress in complexity and functionality along with the continuing study of AC, it may be perfectly reasonable to propose to hook two human brains together in such a way that both individuals would be able to share their conscious experiences. This technique might be described as the ultimate test of subjective sentience, because unlike the development of an objective definition of consciousness, this sort of integral cognition would allow one subjectively conscious human to report the existence or non-existence of a conscious mind in a computer.
The ethics of artificial consciousness
If it was certain that a particular machine was conscious its rights would be an ethical issue that would need to be assessed (e.g. what rights it would have under law). For example a conscious computer that was owned and used as a tool or central computer of a building or large machine is a particular ambiguity. Should
laws be made for such a case, consciousness would also require a legal definition (for example a machine's ability to experience pleasureor pain). Because artificial consciousness is still largely a theoretical subject such ethics have not been discussed or developed to a great extent, though it has often been a theme in fiction (see below).
"'Rights as of 2003:"'
The rules for the 2003
Loebner Prizecompetition explicitly addressed the question of "Robot Rights."
"61. If, in any given year, a publicly available open source Entry entered by the University of Surrey or the Cambridge Center wins the Silver Medal or the Gold Medal, then the Medal and the Cash Award will be awarded to the body responsible the development of that Entry. If no such body can be identified, or if there is disagreement among two or more claimants, the Medal and the Cash Award will be held in trust until such time as the Entry may legally possess, either in the United States of America or in the venue of the contest, the Cash Award and Gold Medal in its own right".
http://loebner03.hamill.co.uk/docs/LPC%20Official%20Rules%20v2.0.pdf The competition was directed by David Hamill and the rules were developed by members of the Robitron Yahoo group. The suggestion for granting rights to the AI was made in http://tech.groups.yahoo.com/group/Robitron/message/687
Artificial consciousness in literature and movies
future historyinstances of artificial consciousness:
*Neuromancer and Wintermute from William Gibson's "Neuromancer".
*Aura from the .hack// series.
Chiifrom the Chobitsanime series.
*Skynet from "
The Terminator" series of films.
Netnavis from " Megaman NT Warrior"
Vanamondein Arthur C. Clarke's " The City and the Stars"
*The Ship (the result of a large-scale AC experiment) in
Frank Herbert's "" and sequels, despite past edicts warning against "Making a Machine in the Image of a Man's Mind."
Orson Scott Card's " Speaker for the Dead", " Xenocide", " Children of the Mind", and "Investment Counselor"
HAL 9000in ""
Steven Spielberg's ""
*Data in "
*P-1 in the 1970s book "The Adolescence of P-1"
Isaac Asimov's "Robot Series"
*Andrew Martin in "
The Bicentennial Man"
*The Technocore in
Dan Simmons' "Hyperion" and "Endymion" series (see Hyperion Cantos)
*The Minds in Iain M. Bank's Culture novels.
*The Sentient Intelligence in
Peter F. Hamilton's " Commonwealth Saga" and sequel.
*Johnny 5 in "
Short Circuit" and sequel.
Robert A. Heinlein's short stories and novels feature AI/AC plots and discussion. See " The Moon Is a Harsh Mistress" (co-starring a networked supercomputer named Mike), " Time Enough for Love" (Minerva/Athena, another world-spanning computer), " The Number of the Beast" (The Gay Deceiver, a supernaturally-altered personal flying craft) and, arguably, the eponymous heroine in "Friday".
*The Bomb in
*Kryten and Holly in
*Durandal, Tycho, and Leela from the
*Many of the characters in
Masamune Shirow's Ghost in the Shell
KITTand KARR from Knight Rider(Note that it was only hinted that K.I.T.T. had essentially a mind of his own and can 'think'. However K.A.R.R. was to be exactly like K.I.T.T. but was said to be more 'animalistic' in nature.)
*All characters of the two first Ring novels by
*WALL-E and EVE in "
Identity of indiscernibles
Philosophy of mind
William Grey Walter
*Citation | last = Aleksander |first= Igor| year=1995| title= Artificial Neuroconsciousness: An Update|http://web.archive.org/web/19970302014628/http://www.ee.ic.ac.uk/research/neural/publications/iwann.html| publisher=IWANN [http://dblp.uni-trier.de/rec/bibtex/conf/iwann/Aleksander95 BibTex] [http://web.archive.org/web/19970302014628/http://www.ee.ic.ac.uk/research/neural/publications/iwann.html Internet Archive]
*Citation | last = Baars | first= Bernard | year=1988| title = A Cognitive Theory of Consciousness| url=http://www.nsi.edu/users/baars/BaarsConsciousnessBook1988/CTC_ch01.html| publication-place= Cambridge, MA|publisher= Cambridge University Press
*Citation | last = Baars | first= Bernard | year=1997 | title = In the Theater of Consciousness | publication-place=New York, NY|publisher= Oxford University Press
*Citation | last = Chalmers |first = David| year=1996 | title = The Conscious Mind |publisher=Oxford University Press.
*Citation | last = Cotterill |first =Rodney| year=2003 | contribution = Cyberchild: a Simulation Test-Bed for Consciousness Studies|title=Machine Consciousness|editor-first=Owen|editor-last= Holland|publication-location=Exeter, UK|publisher=Imprint Academic
*Citation | last = Franklin | first = Stan | year = 1995 | title = Artificial Minds | publication-place = Boston, MA | publisher = MIT Press
*Citation | last = Franklin | first = Stan | year = 2003 | contribution = IDA: A Conscious Artefact | title = Machine Consciousness | editor-first = Owen | editor-last = Holland | publication-place = Exeter, UK | publisher = Imprint Academic
*Citation | last = Freeman | first= Walter | year = 1999 | title = How Brains make up their Minds | publication-location = London, UK | publisher = Phoenix
*Citation | last = Haikonen| first = Pentti | year = 2003| title= The Cognitive Approach to Conscious Machines |publication-location=Exeter. UK|publisher=Imprint Academic
*Citation | last = Sun | first= Ron | year =1999 | title = Accounting for the computational basis of consciousness: A connectionist approach|journal= Consciousness and Cognition| volume=8 | pp.529-565 | date= December 1999
*Citation | last = Sun | first= Ron | year = 2001 | title = Computation, reduction, and teleology of consciousness | journal =Cognitive Systems Research| volume=1|number =4| year = 2001|pages=241-249
*Citation | last = Takeno| first = Junichi | year = 2005 | last2= Inaba |first2=K| last3= Suzuki|first3= T.| title = Experiments and examination of mirror image cognition using a small robot | journal = The 6th IEEE International Symposium on Computational Intelligence in Robotics and Automation | pages =493-498 |publisher = CIRA 2005|publication-location= Espoo Finland | date= June 27-30, 2005 |url=http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=1554325
*Haikonen, Pentti (2004), "Conscious Machines and Machine Emotions", presented at Workshop on Models for Machine Consciousness, Antwerp, BE, June 2004.
*Baars, Bernard J and Stan Franklin. 2003. How conscious experience and working memory interact. Trends in Cognitive Science 7: 166–172.
*Franklin, S, B J Baars, U Ramamurthy, and Matthew Ventura. 2005. The role of consciousness in memory. Brains, Minds and Media 1: 1–38, pdf.
*Casti, John L. "The Cambridge Quintet: A Work of Scientific Speculation", Perseus Books Group , 1998
*McCarthy, John (1971-1987), "Generality in Artificial Intelligence" [http://www-formal.stanford.edu/jmc/generality/generality.html] . Stanford University, 1971-1987.
*Pharoah M.C. (online). [http://homepage.ntlworld.com/m.pharoah/ Looking to systems theory for a reductive explanation of phenomenal experience and evolutionary foundations for higher order thought] Retrieved Dec. 13, 2007.
*Suzuki T., Inaba K., Takeno, Junichi (2005)," Conscious Robot That Distinguishes Between Self and Others and Implements Imitation Behavior", ( Best Paper of IEA/AIE2005), Innovations in Applied Artificial Intelligence, 18th International Conference on Industrial and Engineering Applications of Artificial Intelligence and Expert Systems, pp. 101-110, IEA/AIE 2005, Bari, Italy, June 22-24, 2005.
*Takeno, Junichi (2006), "The Self-Aware Robot -A Response to Reactions to Discovery News-" [http://www.d6.dion.ne.jp/~takenof/SAR-LAL-Takeno.pdf] , HRI Press, August 2006.
*Sternberg, Eliezer J. (2007) "Are You a Machine? Tha Brain the Mind and What it Means to be Human." Amherst, NY: Prometheus Books.
* [http://www.senses.info Site] of
Steven Ericsson-Zenith's "Explaining Experience in Nature" information site.
* [http://www.cogsci.rpi.edu/~rsun/conscious.html Ron Sun's papers on consciousness]
* [http://www.inl.gov/adaptiverobotics/humanoidrobotics/ethicalconsiderations.shtml Humanoid Robotics Ethical Considerations]
* [http://www.intelligent-systems.com.ar/intsyst/ethics.htm Scientific Ethics]
* [http://www.swartzneuro.org/docs/aleksander_presentation.ppt Artefactual consciousness depiction by Professor Igor Aleksander]
* [http://consc.net/chalmers/ David Chalmers]
* [http://consc.net/online/1.4a Online papers on the possible mechanisms of Higher-Order Thought]
* [http://www.aslab.org/public/events/moc ESF Models of Consciousness Workshop] and its [http://www.esf.org/generic/1650/EW0296Report.pdf Scientific Report]
* [http://www.aslab.org/public/events/mcc Machine Consciousness - Complexity Aspects Workshop]
* [http://www.rs.cs.meiji.ac.jp/Takeno_Archive/DiscoveryNewsRoboemotion020905.pdf Robot In Touch with Its Emotions 5-Sep-2005]
* [http://www.rs.cs.meiji.ac.jp/Takeno_Archive/DiscoveryNewsAwareRobot211205.pdf Robot Demonstrates Self-awareness 21-Dec-2005]
* [http://www.conscious-robots.com/ Internet Portal dedicated to Machine Consciousness]
Open Source Software Projects
* [http://adsproject.sourceforge.net/ads-ac/index.php/Main_Page ADS-AC -- An experimental Open Source program which implements Absolutely Dynamic System, a proposed mechanism for AC]
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