What are the origins of life?
What is life? is the title of an influential book by Schroedinger (1944). The current answer is, implicitly: that is ‘life’ which reproduces or replicates and is subject to natural selection.
But this answer includes viruses, phages and prions – which hardly seem to be ‘alive’ in that they lack a dynamic metabolism; and also some forms of crystal – which are usually regarded as certainly not-alive (Cairns-Smith, 1990). Furthermore, some economic theories and computational programmes explicitly use the mechanisms of natural selection - and these are not regarded as part of biology.
Strikingly, there has been no success in the attempts over sixty-plus years to create life in the laboratory under plausible ancestral earth conditions – not even the complex bio-molecules such as proteins and nucleic acids. It has, indeed, been well-argued that this is impossible; and that ‘living life’ must therefore have evolved from an intermediate stage (or stages) of non-living but evolvable molecules such as crystals – perhaps clays (Cairns-Smith, 1987). But nobody has succeeded in doing that in the lab either, despite that artificial selection can be orders of magnitude faster than natural selection.
Since there is no acknowledged boundary dividing biology and not-biology, then it would seem that biology as currently understood has zero validity as a subject. What are the implications of our failure to divide the living from the non-living world: the failure to draw a line around the subject? Well, since there is no coherent boundary, then common sense leads us to infer in that case either everything is not-alive or everything is-alive. If nothing is-alive, not even ourselves, there seems to be no coherent possibility of us knowing that we ourselves are not-alive, or indeed of anything knowing anything – which, I take it, means we should reject that possibility as a reductio ad absurdum.
Alternatively, the implication is that if anything is-alive, then everything is-alive, including the mineral world – so we dwell in a wholly animated universe, all that there is being alive but – presumably – alive in very different degrees and with different qualities of life. This inference I intend to regard as valid: it will be my working metaphysical assumption, and is one to which we will return later.
So; if life is to be regarded as universal, it seems that the presence of ‘life’ can no longer be used as definitive of biology; and since reproduction/ replication is also inadequate, then we need a new basis or principle around-which may be made a different definition of the subject ‘biology’. I will argue, below, why this new principle should be ‘development’.