Chapter 2: The Glass Sponge
In the days of ubiquitous computers and AI, it is natural, almost inevitable, to ask about the relationships between living systems and these artifacts. Do organisms and computers do essentially the same thing with different materials? Similarities between the two do arise, often unexpectedly, but it's also important to recognize dissimilarities. One difference is that much of what a cell does, its main business, is something a computer never has to do. A great deal of the activity in a cell is concerned with maintaining itself, keeping energy coming in, keeping a pattern of activity going despite decay and turnover in materials. Within living systems, the activities that look like the things computers also do -- electrical switching and "information processing" -- are always embedded within a sea, a mini-ecology, of other chemical processes. In cells, everything that happens takes place in a liquid medium, subject to the vicissitudes of the molecular storm and all the chemical digressions that living systems engage in. When we build a computer, we build something whose operation is more regular and uniform; we build something that will be distracted as little as possible by the undirected ruminations of its chemistry."
In cells, the processes of life involve imparting order upon a molecular storm and the imperfect herding of ions. This is nothing like what goes on in any machine we've built. We generally build machines to be predictable and restricted in their activities, even if we might then use them to simulate more chaotic goings-on. To describe the intricate materials in cells as "machinery" is right in some ways and wrong in others.