A bit of a rant today: Nobel laureate Paul Nurse has an article in last week’s issue of Nature that strikes me as having a bunch of buzzwords but a misguided message. In Life, Logic, and Information, Nurse becomes the latest in an endless line of prognosticators to claim that a major transition is near, this time in biology.
He also uses the popular buzzword in the emergence/complexity sense of the word (see Stuart Kauffman), which brings on all sorts of holistic connotations.
Living organisms are complex systems made up of many interacting components, the behaviour of which is often difficult to predict and so is prone to unexpected outcomes. Systems analyses of living organisms have used a variety of biochemical and genetic interaction traps with the emphasis on identifying the components and describing how these interact with each other. These approaches are essential but need to be supplemented by more investigation into how living systems gather, process, store and use information, as was emphasized at the birth of molecular biology.
Information processing? I don’t remember that in any of my biochemistry courses. It sounds like something someone from my IT department might say if he tried to grossly oversimplify molecular biology to the point that it wasn’t molecular biology any more.
The lac operon, for instance, isn’t *really* an electronic switch. Skipping over the biochemical interaction coefficients is fatal to one’s understanding if he or she uses the lac operon model to explain gene and protein regulation in the Eukaryotic cell.
At a more fundamental level, at least Nurse acknowledges that reductionist approaches are necessary to understanding emergent behavior in cell biology. But he suggests that you really can get additional form of understanding or knowledge about systems in ways other than breaking it down into its components.
Reductionism versus holism or synthesis as modes of building understanding are not new arguments however. E.O. Wilson expertly covers this topic in Chapter five of his book Consilience:
To dissect a phenomenon into its elements, [...] is consilience by reduction. To reconstitute it, and especially to predict with knowledge gained by reduction how nature assembled it in the first place, is consilience by synthesis. That is the two-step procedure by which natural scientists generally work: top down across two or three levels of organization at a time by analysis, then bottom up across the same levels by synthesis.
And Paul Nurse, as well as others who mention information processing in biological systems, remind me of people who have forgotten that synthesis is capable only *after* reductionist explanations are sufficiently complete. Clearly, we’re not there yet for understanding the complexity of the cell, or of the brain, to begin sythesizing artificial versions.