Definition of Life, continued

The following is a contribution from MD James Lavers to the discussion that started on this blog on the "Definition of Life" on 17 November 2010. For previous contributions to this discussion, please refer to that posting:


This conversation continues to take some interesting turns. I hope that my further muddled thoughts on the points raised will be of some interest.

It seems Katie and I are in agreement on the majority of the debate, perhaps unsurprisingly given we have touched on some of these issues before and found considerable common ground; conversations that were always compelling and challenging and are much missed. She has certainly expanded substantially on my suggestion that we are all just incomprehensibly complex biochemical machines thus eliminating the need to draw any distinction between life-forms in terms of what it means to be alive or indeed in possession of free-will.

I am uncertain how much my thoughts will add to such a well trodden philosophical debate as that of free will vs determinism, but for what its worth I will try and find a coherent line of thought.

I do not like the word determinism. To me it implies that everything is pre-determined and inevitable. This physical determinism, which is admittedly only one strand of the several determinist arguments, implies that there is only one possible future, which is being acted out blindly by everything, every atom, every quark in the Universe to a foregone conclusion. There seems to be substantial doubt over this view, not least because of the sub-atomic uncertainty that you have alluded to in your comments. However I do not believe that the presence of this physical indeterminism infers the existence of free will. While it seems there is room for variation and uncertainty, there is no evidence that we have the ability to influence these uncertainties in any way. We cannot control or choose the instantaneous position of an electron. The uncertainty that exists is external to our decision making and affects us indistinguishably from any other event. We react as we always do, in the way we are programmed to by our biochemical configuration through the stimulation of neuroreceptors by neurotransmitters.

As such, my personal view is closest to a type of Biological Determinism. I imagine that we are all independent physical entities (although the word entity is in itself problematic given not a single atom remains constantly as a part of us throughout our lifetime) that inhabit an uncertain Universe, but that our individual reactions are mediated purely through our biochemical responses to external stimuli, controlled by our genetic make up. An analogy might be that of a computer programme. When it is written, the programmer does not know exactly what it will do and when, but it has no free will, it just reacts to stimuli in the way it was designed to. Clearly, the situation for human beings is more complex than that, because we have an ability to change and will not act in the same way throughout our life. For the solution, I once again have Katie to thank for one of the most interesting and important conversations I have ever had. It seems that the genome does not produce an intransigent code as I had imagined but it acts more like a database from which receptors governing different things may be upregulated and downregulated. The numbers of particular receptors up and down-regulated at any one time affects mood, behaviour and pretty much anything. In experiments (in Humming birds I think), this regulation has been shown to be influenced by environmental factors. In one fell swoop this provides a logical route for the environment to effect the biologically mediated behaviour of humans (including in utero) and may solve another well trodden philosophical path, the debate of nature vs nurture. This model would mean that when considering doing something the idea of not doing it because everything is predetermined and inevitable and thus you have no power to affect anything is nonsensical. You are able to influence your environment with your actions and thus also the reactions of other people. What you cannot do is make a free decision over whether you will do it or not. The chemicals in your brain do that. But the evolution of awareness in the human brain provides the illusion of free will by necessity, as the alternative would mean being a confused passenger on a ride where you feel no association at all with the decision processes.

I admit my argument relies on time being a linear unidirectional entity, which while our perception as humans, may be just evolutionally how it is useful for us to perceive it within the frame of reference of our own existence. However, even if time is capable of being perceived in different ways, it is unlikely that this would make the Universe less deterministic.

You comment in your answers ‘Even if the concept of determinism is correct, it is for us a useless concept.’ Again I am afraid I do not agree. It is true it is a fairly depressing thought, although for me the pursuit of truth is in itself reason enough to try and understand, regardless of what you might find. However, I also believe it has far reaching implications for our society. To what extent are people really responsible for their actions? If some sort of biological determinism is indeed the reality, then the answer is fairly uncomfortable. Should this influence the way society acts in for example punishing criminals? Almost certainly. It is not as simple as saying we should completely scrap the penal system. I imagine that the environmental factors of society have a powerful effect on us. We have evolved to become highly social beings and social pressure and the threat of incarceration effect behaviour, even if in a biochemically mediated way. However, with consideration and research, better understanding of how and why we act may be able to produce a fairer society in a range of areas. Certainly it is worth considering, although clearly care would be needed to avoid producing a ‘Big Brotheresque’ society, where humans were controlled using environmental cues in a mechanistic fashion to produce uniform, conformist beings, which have lost the invention and variation that are such positive traits in our species.

Finally, I would like to return to the original subject matter to reassert my disagreement with what you describe as the exaggerated attention given to the emergence of the first single-cell organism. I think there are two moments in the history of the universe that completely defy logical explanation. The first is the Big Bang itself, where for no reason that we can yet understand an incomprehensibly enormous mass suddenly emanated from one single point. From a fraction of a second after the Big Bang, the expansion of the universe, the formation of stars, galaxies and planets follows a logical process. We have formulated rules that appear to conform to our observations. But what caused that initial moment? What caused the birth of the Universe? From what did it come from? What was there before? Nothing we understand can explain it and likely never will.

Only slightly less extraordinary to me is the first emergence of life. I don't see this as a ‘natural next step of the evolution from the Big Bang via the formation of subatomic particles, atoms, molecules, stars and galaxies,’ as you do. It is something completely different. It is unlikely it was a unique moment, given the incomprehensible number of stars and planets in the Universe, but it is extraordinary and for me, again without logic. What possible reason is there that molecules, to all intensive purposes inanimate objects should start acting together for a common goal? To reproduce and develop? There was no evolution before. It is like the Big Bang but on Earth. The single point from where all life has emanated. From that moment the diversification and development of life on Earth, has again followed a logical process, this time governed by the laws of evolution. That does not make the process of evolution anything less than extraordinary, but it does follow a pattern that we can understand. That an ability to perceive and process the reflections of a section of the electromagnetic spectrum has been developed, to the extent that a representation of what surrounds us can be constructed is unbelievable. Light was not designed to be used to see. It is emitted from stars as a byproduct of nuclear reaction. Evolution has provided the tools to utilise it to confer a survival advantage. It is remarkable. But it follows a logical course of development, which can even be followed by studying organisms with variously developed abilities to perceive light and react to it. A process of slow improvement can be traced. It is logical.

And yes, even with all that has developed, vision, hearing, motor function, sensation, there is no doubt that the self-aware brain is evolution's most sparkling achievement. The crown jewels. A stunning work worthy of awe and wonder, with the ability to perceive beauty, humour, love and even itself. That such a seemingly haphazard process as evolution could create such a work of art is remarkable and worth celebrating. But there is a process there. A process which started with that very first life form. A process that is rational. Why that first life form first came together, at least for me, is not logical.