The materialistic interpretation
Materialistic doctrine is based on the belief that the functioning of living organisms can be reduced entirely to physical and chemical processes. Some of the propagators of materialism, zealous to associate life with inanimate matter, even use machine-like terminology. For example, biologist Richard Dawkins describes living organisms in terms of mechanisms, replicators and robots. Ironically, this, in fact, contradicts materialism:
It has for some time been generally supposed that organisms are mechanisms and that, since mechanisms work in accordance with physical and chemical laws, organisms must also do so... Unfortunately this assumption has been misconceived to mean that organisms must be wholly explicable as the resultants of physical and chemical laws because mechanisms are. Actually it means exactly the opposite. For mechanisms are not wholly explicable as the resultants of the operation of physical and chemical laws. (Polanyi and Prosch, 1975, p.168)
Machines are purposely built and they can be fully understood only in that context. So, if life forms are machines, the same should apply.
Leaving this philosophical point aside, explaining life in terms of the physical and chemical properties of its components is not straightforward. Although science has identified most of the necessary chemicals and can describe fairly well many processes in a cell, why a living cell functions at all remains a mystery. It says nothing, for example, on why cells replicate (especially when the process goes from a simple to a more complex structure). The replication mechanism may be encoded in the DNA, but this does not explain why and how it is encoded in the first place:
Whatever the origin of a DNA configuration may have been, it can function as a code only if its order is not due to the forces of potential energy. Just as the arrangement of a printed page is and must be extraneous to the chemistry of the printed page, so the base sequence in a DNA molecule is and must be extraneous to the chemical forces at work in the DNA molecule. (ibid. p.172)
Thus, the boundary conditions that determine the structure and organisation, ‘must consist of principles other than those of the material they bound' (ibid., p.177). This, of course, does not apply only to replication, but also metabolism, growth, cell cooperation, etc.
There are a number of other issues worth mentioning. While alive, an organism maintains a highly ordered, low-entropy state. Silver writes:
The fact that the contents of the cell include very large (highly improbable) molecules, and that the cell is a highly ordered (highly improbable) structure, implies that living matter is in a state of comparatively low entropy as compared with the disorganized mess of small molecules into which it disintegrates when it dies. (1998, p.323)
This is contrary to the second law of thermodynamics. Although it does not break this law because it is an open system, the question remains why it persistently acts against it. If life is nothing more than chemistry and physics, why does a living cell behave so differently than a cell that has all its components intact, but is not alive?
Explaining ontogeny (the sequence of events involved in the development of an individual organism) is also a problem. Laszlo states that ‘the principles of the regulatory circuits involved in embryonic development are not known... almost nothing is known about how the human organism instructs itself to build, for example, a human hand' (1993, 101). The development of the embryo requires the ordered unfolding and coordinated interaction of billions of dividing cells (e.g. some cells become a liver and some a thumb at a precise time and place). If this process were entirely coded by genes, the genetic program would have to be complete and detailed and yet flexible enough to ensure the differentiation and organisation of a large number of dynamic pathways under a potentially wide range of conditions. Yet, the genetic code is the same for every cell in the embryo. Anticipation of embryo development is more than a technical issue:
Since the chemical compound DNA is assumed to act only chemically, it cannot vary its actions in the way a builder with a mind can. Therefore, there must either be another element in the organism that can function as a builder, merely using the DNA compound as its blueprint, or, as the theory supposes, the DNA must merely be responding chemically to chemical compounds. In the latter case, if it acts differently at different times, there must be different chemical compounds for it to react with at different stages of embryonic development. But these compounds must be called into existence only at the end of the embryo's previous stage. Timing is therefore most important. No theory yet exists to explain how this can be done in a strictly chemical way. The development of such a theory is rendered more difficult because, as Driesch first showed in his work with sea-urchin embryos, there seems to be some resilience possible in the development of tissues. Some tissues can sometimes seemingly be "pressed into" undergoing changes they do not normally undergo, because some part of the embryo has been prevented from developing in its usual way. It is almost, in these cases, as if there were a builder who has had to use some ingenuity because of shortages of one material or another or because something has previously been built erroneously and he must now build upon and around this. (Polanyi and Prosch, 1975, p.166)
This is reinforced by the findings that some organisms ‘possess programs of repair that could not have been naturally selected: the kind of damage which they repair is not likely to have befallen their progenitors in the entire history of a species' (Laszlo, 1993, p.102).
The problems that the materialistic framework faces are not limited to the internal workings of living beings, but extend to some widespread behavioural aspects of complex organisms. One among many examples highlighted by biologist Rupert Sheldrake is the European cuckoo that lays its eggs in the nests of birds of other species. The young never see their real parents. Towards the end of the summer the adult cuckoos migrate. About a month later, the young cuckoos congregate and also migrate to the same region. They instinctively know that they should migrate, when to migrate, in which direction they should fly and what their destination is. Materialists believe that this is all somehow programmed by their genes, but this is far too complex behaviour to make this explanation likely.
The results of a series of experiments meant to test whether learned behaviour patterns are inherited are equally puzzling. Behavioural psychologist William McDougall in the early 1920s trained some rats to perform a simple task. The experiment involved 32 generations of rats and took 15 years. Later generations of rats (separated from the previous generations) consistently learned more rapidly than the previous ones, the last over ten times faster than the first one. More significantly, when separate experiments in other parts of the world replicated the original one, the first generation of rats learned almost as rapidly as McDougall's last generation. A number of them even performed the task correctly immediately, without making a single error.
The above suggests that not all biological functions cannot be comfortably explained within the materialistic paradigm. Life seems to be more than just molecular reactions. Polanyi and Prosch conclude:
We must admit that we do not yet have the reduction of living processes to physical and chemical laws that modern biologists seem to think we can have. We not only have not proved that these adaptive aspects of the DNA's building capacity can be reduced wholly to physical and chemical operations, but we never can do so. (1975, p.167)
Most religions accept a dualistic nature of life, meaning that it cannot be cut down to the physical or chemical properties of the organism. A non-material component is, in fact, considered essential for life. Almost every spiritual tradition recognises the existence of soul, spirit or atman, which is one of the main differences between them and the materialistic perspective. However, it is unclear how this component interacts with the body and to what extent it can exist independently from the body (before birth or after death). Moreover, it is also uncertain which organisms have this non-material component. Philosopher Descartes, for example, who attempted to provide rational foundations for dualism, reserved it only for human beings, but this seems arbitrary.
The contribution of philosophy
Vitalism is a major contribution of philosophy to the debate about the nature of life (Henri Bergson being its best known exponent). Its main input was to point out the incompleteness of reductionist and mechanistic interpretations. Like the ancient Greek philosophers, including even Aristotle, Vitalism argues that the difference between living organisms and inanimate bodies cannot be explained solely in material or physicochemical terms. Living forms, it is claimed, have an additional, non-material, vital element - a universal life force, which may or may not be capable of existing apart from its hosts. The nature of the life force was debated even earlier by numerous philosophers of which some (e.g. Paracelsus) believed that it is an external property and others that it is an internal, spontaneous, event. Life as an explanatory and evaluative concept appealed to many philosophers in the 19th century as a reaction to scientific materialism, although the success of synthesising an organic compound artificially in the first half of the same century weakened dramatically the Vitalist position. Failed attempts to find vital élan in the body which, in fact, would have reduced it (if they were successful) to another type of physical force similar, for example, to the electro-magnetic force, confused the matter further. Vitalism resurfaced in the 20th century in the work of the already mentioned Hans Driesch, when he discovered that despite extreme interference in the early stages of embryological development, some organisms nevertheless develop into perfectly formed adults. He proposed the existence of a soul-like force which guides the development of an embryo (in his later writings, Driesch argued that all life culminates ultimately in a ‘supra-personal whole'). Such conclusions are, of course, only interpretations of data available at that time. However, there are further reasons why prevailingly dismissive attitude at present towards similar ideas may be inadequate. They will be considered below.
- . Consequently as biologist Morowitz puts it ‘the study of life at all levels, from social to molecular behaviour, has in modern times relied on reductionism as the chief explanatory concept' (1981, p.34-35).
- . Polanyi concludes: ‘Biologists will tell you that they are explaining living beings by the laws of inanimate nature, but what they actually do, and do triumphantly well, is to explain certain aspects of life by machine-like principles. This postulates a level of reality that operates on the boundaries left open by the laws of physics and chemistry' (1969, p.154).
- . Entropy can also decrease in some inanimate open systems (sometimes called dissipative structures) but not with an increase of functionally different dynamic processes and non-uniformed (but not random) complexity at the same time, as in the case of life.