Several weeks ago in Time magazine, I read an article which gripped me and set my mind working intensely for days upon end. The article focused on the visions of a respected science writer and inventor, Ray Kurzweil, who is closely affiliated with a movement known as the 'singularitarians'. 'Singularitarians' predict the arrival in about thirty years of a technological revolution called the 'singularity' which will change human society as we know it. This revolution will arrive in the form of artificial intelligence. The article is right here http://http//www.time.com/time/health/article/0,8599,2048138-1,00.html.
Before continuing further, it is important to define the meaning of artificial intelligence. Currently it is split into two kinds: weak A.I., which has already been achieved to an extent, and strong A.I., which has not, and many including myself would argue, never will be. Weak A.I. involves the creation of computers and robots which can replicate human behavior: our speech, motion, and the like. Strong A.I. refers to the creation of machines which not only mimic the physical actions of humans, but which are self aware and think just as we do. Ray Kurzweil bases his prediction for the coming of strong A.I. in 2045 off the idea of exponential growth. He examines the rate of progress in computing power over the past hundred years or so, which has grown exponentially (that is, the rate of improvement has become faster itself), and extrapolating off this growing rate of progress, predicts that computers will be made by 2045 which fully replicate the structure of the brain and are therefore conscious just as we are. He believes, in fact, that they will surpass human intelligence.
Such ideas make for fantastic headlines which draw readers magnetically. There is something quite mind churning and provocative about the idea of conscious machines. Singularitarians such as Kurzweil however, are computer scientists and engineers, and coming from such backgrounds ground their quest for A.I. in a fundamental philosophical assumption which they fail to truly examine themselves: the belief in a metaphysically materialistic worldview. By materialism I do not refer to anything relating to consumerism, but to the metaphysical assumption that the foundation of all reality is physical matter, and everything, including the human mind, is a product of physical matter and its interactions. Proponents of strong A.I. believe that the human mind, or 'essence', if you will is wholly reducible to the interaction of the brain's material parts. It can therefore be recreated with robotics.
Many casual readers of the Time article would likely fail to question this assumption, or rather would look away repulsed at the concept of conscious machines, unable however to provide a logically coherent argument against its possibility. My stance against materialism and the possibility of strong A.I. arises from what many philosophers of mind have termed the 'hard problem of consciousness'. The hard problem of consciousness refers to the logical explanatory gap in how one is able to describe all the working parts of a physical structure, such as the human brain, and then explain how, due to its physical interactions, it begins to feel and become self aware. Neuroscience is able to find the brain's nerve correlates of various feelings and thoughts, but is unable to explain how these nerves actually cause conscious experience. If one takes any arrangement of matter, and then proceeds to make it interact in any way, the laws of physics tell us nothing more than the physical interactions which should then ensue. There is nothing in any law of physics which tells us when matter should begin to have conscious experiences. There is no 'Newton's fourth law'. Moreover, any progress in physics will also yield only new laws of physical interactions, which will still leave this explanatory gap: why is it that when physical matter is arranged in a certain way, consciousness, as if from nowhere, arises? The philosopher of mind 'David Chalmers' is perhaps the strongest proponent of this problem. Here is one article of his in which he summarizes the issue. It is long and tough to read, but if one wants to it is well worth the time http://http//consc.net/papers/facing.pdf I think it is important to mention that the hard problem of consciousness is recognized not just by philosophers but by a number of notable quantum physicists today. The esteemed american physicist Henry Stapp sees this problem as the achilles heel of materialism as a metaphysical worldview. He is himself a proponent of mind body dualism: the metaphysical belief that the mind is separate from the body, and in his theory, acts through the brain.
Dualism is an old philosophy formulated by the french philosopher Descartes. He was most famous for his famous words "I think therefore I am", alluding to the idea that since he was able to think he could not doubt that his mind existed. He could however doubt that the physical reality around him existed, as his senses of sight, hearing etc. could all be illusions. He theorized that the mind was an immaterial substance, or soul, which controlled the material body. Dualism fell out of fashion with the development of Newton's mechanics. Following this development, the world was believed to be completely deterministic: all future events were caused directly by past ones, and so could be predicted to infinity. If some immaterial entity were to act upon the physical world, it would violate this fundamental postulate of Newtonian physics. With the coming of the twentieth century, this view was shattered. Indeed all twentieth century physics is so far removed from everyday experience, it is hard to accept if one is not acquainted with the field. Einstein showed, astoundingly, that time is in fact non linear, and travels at different rates for different observers. Subsequently, with the advent of quantum mechanics, the concept of determinism was overthrown. At the quantum mechanical level, events are somewhat random, and cannot be predicted for sure, but only given a probability of happening. That is to say, nothing at the subatomic level of physical reality is for sure set to happen. There are only probabilities. This opens up the door to dualism again. Consciousness, if a separate entity, could perhaps influence this randomness. This is the angle physicists such as Henry Stapp take. He is not the only one, and the noted Oxford University physicist Roger Penrose has devised his own theory in which consciousness is not the product of the brain but a fundamental entity of the universe itself. His ideas are heavily criticized by his materialistic peers, but seeing as materialism is a common prejudice among scientists today brought up with such a world view, and scientists are only beginning to investigate the true nature of consciousness, all bets are off at this point.
Am I a proponent of dualism? Perhaps, I haven't quite decided. I personally find the view of neutral monism more compelling: the idea that matter and mind are not separate, nor the same, but two different properties of some other more fundamental reality (the famous late twentieth century physicist David Bohm and 17th century philosopher Spinoza took a similar stance). One thing I'm sure of though is that I'm not a proponent of materialism, and do not think I'm a robot, as proponents of the quest for strong A.I. would have me believe. The study of consciousness is in its infancy, and I believe singularitarians among others should take a second to question, though not necessarily reject, their materialistic worldview. True scientific understanding cannot be advanced when prejudices go unexamined. I'm sorry this post was so long, but I had a lot of ideas to put out there.
