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1 " Superimposed on the hierarchical framework of defined components of a cell there is another layer. This second layer is highly flexible and can take on an almost infinite variety of forms, like soft and responsive flesh on a bony skeleton. The deep question is whether this higher layer in the construction of cells is itself organized. Are there hierarchies, or at least rules, in the protein-modifying, RNA splicing, gene-regulating processes of a cell? If so, then we have a chance of understanding them. If not, we will never know exactly what a cell will do next. If the detailed chemistry of the cell is simply the outcome of a historical ragbag of ad hoc interactions, then it will be no more predictable than the weather. I do not have an answer to this question. But two features of cells might be relevant. One is a sense of time, or causation - knowledge of the way that things in the real world follow in a certain sequence. The other is integrity, which enables a cell to distinguish between what belongs to itself and what belongs to the outside world. "
― , Wetware: A Computer in Every Living Cell
2 " I described living cells as being crammed full of protein molecules. Acting individually or in small assemblies, they perform reiterated molecular processes that can be regarded, I argued, as a form of computation. Moreover, large numbers of proteins linked into huge interacting networks operate, in effect, like circuits of electrical or electronic devices. Networks of this kind are the basis for the animate wanderings of single cells and their ability to choose what to do next.Here I have broadened the view to encompass multiple cells - 'societies' of cells. Through a variety of strategies - including diffusive hormones, electrical signals, and mechanical interactions - the computational networks of individual cells are linked. During evolution, cells acquired the capacity to work together in social groups; it became advantageous for most cells to become highly specialised. Liver cells, muscle cells, skin cells, and so on abandoned their opportunities for unlimited replication. They began the communal expansion of interlinked abilities that led to the plants and animals we see around us today. But the basis of this diversification of cell chemistry was yet another form of computation - one that operates on DNA. Control mechanisms, again based on protein switches, created extensive but subtle modifications of the core genetic information. "
3 " So I did indeed set out, as John Steinbeck says in his gavels with Charley, "not to instruct others but to inform myself. "