What do we mean when, in both formal scientific and folk language, we use the word "life?" What is "life?"
The question may appear trite at first consideration because we all have an instinctual recognition or acknowledgment of being alive. Yet this instinctual notion is a largely unexamined one, as a brief examination will show.
All biological systems are taken, in the formal scientific definition of "life," to be living "things." The notion of a plant as living thing, however, remains to be properly acknowledged in our folk notions of what it means to be "living." Buddhists, for instance, consider it unethical for humans to "kill" other living things for food. Yet, in the scientific definition of the word "life," that is exactly what they do when they eat plants! Is plant life so different from animal life that we may be morally and ethically justified in not reckoning plants as living in our interpretation of the ethical command: "Thou shalt not kill?"
The example of the apparent moral-ethical contradiction in vegetarianism shows why an inquiry into the concept of "life" is important, for it transcends consideration of the distinction between plant and animal life. Are certain forms of lower animal life so unlike human life that we may "kill" without really having "killed?" If certain lower life forms really are not living then where do we draw the line in the Linnaean hierarchy of animal life with regard to the moral-ethical law: "Thou shalt not kill?" At what level in the Linnaean hierarchy does an animal become so living that we become bound, for the first time, by the command not to kill? In considering this question one becomes conscious of the progression of thought that might lead to a conviction that a "subhuman race" might be exterminated without any moral-ethical consequences for the superior race which does the killing. At the extreme end of the scale is the solipsist who considers himself the only "really living," and might, therefore, refuse to consider himself bound by the moral-ethical injunction not to kill in his dealings with other humans. One, in this regard, is forced to infer an underlying solipsistic outlook to the psychology of some prominent figures in history like Hitler, Mohammed and Stalin.
Nature obviously makes no attempt to help us draw a line between the "really living" and the "not really living" in the Linnaean hierarchy of life. All animals are equipped with an instinctual urge to struggle for survival. We might ask--why do animals struggle for survival? Why are animals both "lower" and "higher" intensely preoccupied with the problem of self-preservation? What is the "thing" of value being preserved in the unceasing Darwinian evolutionary hustle for survival? "Life" is our instinctual response to this question. But then, again, we come to the question--what is life? What about "life" is of such value as to compel the struggle for its perpetuation?
The standard approach to defining life, in the biological sciences, would seem, to the spiritually minded, superficial. Life is defined in terms of the primary functions of biological systems. High on the list of life defining biological functions is the power of reproduction or more simply the power of a biological system to replicate its unique order. But to define life in terms of its self-replicating functions would appear to initiate a vicious circle of definition in which life becomes that which replicates life.
Some biologists would argue (reasonably) that we discard the concept of life as incoherent, and that we should seek, rather, to characterize biological systems without any reference to the "incoherent" concept of life. In this approach, we merely describe and study what biological systems do and avoid shrouding the fact of biology in mystical "life" airs. In this sense, a biological system is that which has the capability to perform certain functions, chief amongst which is the capacity to replicate or reproduce its order. But the significant complicating point in this approach is that there would appear to be nothing that biological systems do which cannot be implemented in artificial intelligence systems. This observation leads to the suggestion that our notion of "life" might well be another in our long list of folk misconceptions, for it raises theoretical problems such as what constitutes, for instance, the essential difference between a fully automated, artificial intelligence program driven, self-replicating apache helicopter and a dragonfly, which makes the first biological and the second non-biological. Surely, to think of the distinction between an artificial intelligence helicopter machine and a dragonfly wholly in terms of difference in engineering material (organic vs inorganic) is so superficial that, in the context of the thinking that the notion of life be discarded in scientific thought, the real value emptiness of maintaining distinction between the categories of the biological and non-biological becomes glaring.
Is the concept of "life," after all, a meaningless concept? In examining this question we may ask ourselves, why do systems described as biological struggle for survival? What is so intrinsically valuable about any given biological systems order as to compel the conjuring up of a highly elaborate and sophisticated paraphernalia in promotion of its perpetuation? We find no tendency in nature for the perpetuation of the order of beautiful or "useful" things. The fact that we find such sophisticated mechanisms in biological systems raises significant questions as to the nature of "life."
A useful approach to the problem of "life" is in terms of what may be observed to be incompleteness of biological systems with regard to the question: why do biological systems struggle for survival? If you look up in the sky and see two squadrons of fighter jets in dogfight you assume that there are pilots in the cockpit. If you know that the fighter jets are fully automated you assume that the dogfight is a human quarrel by jetfighter machine proxy! Why? The answer is that with regard to the motivation to quarrel and fight, jetfighters are incomplete. In same sense could it be proposed that, with regard to the struggle for survival, biological systems as organic materials machines are incomplete. Dawkins selfish genes don't explain the problem either, for although DNA molecule obeys the laws of chemistry in its functions, there are no known laws of chemistry which compel DNA to behave the way it does (as illustration, we don't disobey the laws of physics when we build and fly space shuttles to the moon, yet the laws of physics do not fully explain how or why we build spaceshuttles and fly them to the moon). To seek to answer the question, "why do dragonflies struggle for survival and seek mates for sexual reproduction?" by saying that they only seek to perpetuate their genes is to provide an incomplete answer, for we know that information systems have no intrinsic capacity for self-replication or self-perpetuation; a database manager who values the information must take the initiative.
The writer JohnThomas Didymus is the author of "Confessions of God: The Gospel According to St. JohnThomas Didymus." ( http://www.resurrectionconspiracy.com/ ). If you have found this article interesting you are invited to read the article: ARTIFICIAL LIFE, ARTIFICIAL INTELLIGENCE AND SENTIENCE: WHY DO WE FEAR DEATH? on his blog http://johnthomasdidymus.blogspot.com/2010/06/artificial-life-artificial-intelligence.html
