"Artificial Intelligence has been brain-dead since the 1970s." This rather ostentatious remark made by Marvin Minsky co-founder of the world-famous MIT Artificial Intelligence Laboratory, was referring to the fact that researchers have been primarily concerned on small facets of machine intelligence as opposed to looking at the problem as a whole. This article examines the contemporary issues of artificial intelligence (AI) looking at the current status of the AI field together with potent arguments provided by leading experts to illustrate whether AI is an impossible concept to obtain.
Because of the scope and ambition, artificial intelligence defies simple definition. Initially AI was defined as “the science of making machines do things that would require intelligence if done by men”. This somewhat meaningless definition shows how AI is still a young discipline and similar early definitions have been shaped by technological and theoretical progress made in the subject. So for the time being, a good general definition that illustrates the future challenges in the AI field was made by the American Association for Artificial Intelligence (AAAI) clarifying that AI is the “scientific understanding of the mechanisms underlying thought and intelligent behaviour and their embodiment in machines”.
The term “artificial intelligence” was first coined by John McCarthy at a Conference at Dartmouth College, New Hampshire, in 1956, but the concept of machine intelligence is in fact much older. In ancient Greek mythology the smith-god, Hephaestus, is credited with making Talos, a "bull-headed" bronze man who guarded Crete for King Minos by patrolling the island terrifying off impostors. Similarly in the 13th century mechanical talking heads were said to have been created to scare intruders, with Albert the Great and Roger Bacon reputedly among the owners. However, it is only in the last 50 years that AI has really begun to pervade popular culture. Our fascination with “thinking machines” is obvious, but has been wrongfully distorted by the science-fiction connotations seen in literature, film and television.
In reality the AI field is far from creating the sentient beings seen in the media, yet this does not imply that successful progress has not been made. AI has been a rich branch of research for 50 years and many famed theorists have contributed to the field, but one computer pioneer that has shared his thoughts at the beginning and still remains timely in both his assessment and arguments is British mathematician Alan Turing. In the 1950s Turing published a paper called Computing Machinery and Intelligence in which he proposed an empirical test that identifies an intelligent behaviour “when there is no discernible difference between the conversation generated by the machine and that of an intelligent person." The Turing test measures the performance of an allegedly intelligent machine against that of a human being and is arguably one of the best evaluation experiments at this present time. The Turing test, also referred to as the “imitation game” is carried out by having a knowledgeable human interrogator engage in a natural language conversation with two other participants, one a human the other the “intelligent” machine communicating entirely with textual messages. If the judge cannot reliably identify which is which, it is said that the machine has passed and is therefore intelligent. Although the test has a number of justifiable criticisms such as not being able to test perceptual skills or manual dexterity it is a great accomplishment that the machine can converse like a human and can cause a human to subjectively evaluate it as humanly intelligent by conversation alone.
Many theorist have disputed the Turing Test as an acceptable means of proving artificial intelligence, an argument posed by Professor Jefferson Lister states, "not until a machine can write a sonnet or compose a concerto because of thoughts and emotions felt, and not by the chance fall of symbols, could we agree that machine equals brain". Turing replied by saying “that we have no way of knowing that any individual other than ourselves experiences emotions and that therefore we should accept the test.” However Lister did have a valid point to make, developing an artificial consciousness. Intelligent machines already exist that are autonomous; they can learn, communicate and teach each other, but creating an artificial intuition, a consciousness, “is the holy grail of artificial intelligence.” When modelling AI on the human mind many illogical paradoxes surface and you begin to see how the complexity of the brain has been underestimated and why simulating it has not be as straightforward as experts believed in the 1950’s. The problem with human beings is that they are not algorithmic creatures; they prefer to use heuristic shortcuts and analogies to situations well known. However, this is a psychological implication, “it is not that people are smarter then explicit algorithms, but that they are sloppy and yet do well in most cases.”
The phenomenon of consciousness has caught the attention of many Philosophers and Scientists throughout history and innumerable papers and books have been published devoted to the subject. However, no other biological singularity has remained so resistant to scientific evidence and “persistently ensnarled in fundamental philosophical and semantic tangles.” Under ordinary circumstances, we have little difficulty in determining when other people lose or regain consciousness and as long as we avoid describing it, the phenomenon remains intuitively clear. Most Computer Scientists believe that the consciousness was an evolutionary “add-on” and can therefore be algorithmically modelled. Yet many recent claims oppose this theory. Sir Roger Penrose, an English mathematical physicist, argues that the rational processes of the human mind are not completely algorithmic and thus transcends computation and Professor Stuart Hameroff's proposal that consciousness emerges as a macroscopic quantum state from a critical level of coherence of quantum level events in and around cytoskeletal microtubules within neurons. Although these are all theories with not much or no empirical evidence, it is still important to consider each of them because it is vital that we understand the human mind before we can duplicate it.
Another key problem with duplicating the human mind is how to incorporate the various transitional states of consciousness such as REM sleep, hypnosis, drug influence and some psychopathological states within a new paradigm. If these states are removed from the design due to their complexity or irrelevancy in a computer then it should be pointed out that perhaps consciousness cannot be artificially imitated because these altered states have a biophysical significance for the functionality of the mind.
If consciousness is not algorithmic, then how is it created? Obviously we do not know. Scientists who are interested in subjective awareness study the objective facts of neurology and behaviour and have shed new light on how our nervous system processes and discriminates among stimuli. But although such sensory mechanisms are necessary for consciousness, it does not help to unlock the secrets of the cognitive mind as we can perceive things and respond to them without being aware of them. A prime example of this is sleepwalking. When sleepwalking occurs (Sleepwalking comprises approximately 25 percent of all children and 7 percent of adults) many of the victims carry out dangerous or stupid tasks, yet some individuals carry out complicated, distinctively human-like tasks, such as driving a car. One may dispute whether sleepwalkers are really unconscious or not, but if it is in fact true that the individuals have no awareness or recollection of what happened during their sleepwalking episode, then perhaps here is the key to the cognitive mind. Sleepwalking suggests at least two general behavioural deficiencies associated with the absence of consciousness in humans. The first is a deficiency in social skills. Sleepwalkers typically ignore the people they encounter, and the “rare interactions that occur are perfunctory and clumsy, or even violent.” The other major deficit in sleepwalking behaviour is linguistics. Most sleepwalkers respond to verbal stimuli with only grunts or monosyllables, or make no response at all. These two apparent deficiencies may be significant. Sleepwalkers luse of protolanguage; short, grammar-free utterances with referential meaning but lack syntax, may illustrate that the consciousness is a social adaptation and that other animals do not lack understanding or sensation, but that they lack language skills and therefore cannot reflect on their sensations and become self-aware. In principle Francis Crick, co-discover of double helix DNA structure, believed this hypotheses. After he and James Watson solved the mechanism of inheritance, Crick moved to neuroscience and spent the rest of his trying to answer the biggest biological question; what is the consciousness? Working closely with Christof Koch, he published his final paper in the Philosophical Transactions of the Royal Society of London and in it he proposed that an obscure part of the brain, the claustrum, acts like a conductor of an orchestra and “binds” vision, olfaction, somatic sensation, together with the amygdala and other neuronal processing for the unification of thought and emotion. And the fact that all mammals have a claustrum means that it is possible that other animals
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