Network Logic - Index of
Network Logic - Index of
Network Logic - Index of
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<strong>Network</strong> logic<br />
Boundaries <strong>of</strong> identity<br />
All living organisms have a physical boundary that discriminates<br />
between the system – the ‘self’, as it were, and its environment. Cells,<br />
for example, are enclosed by membranes and vertebrate animals by<br />
skins. Many cells also have other boundaries besides membranes,<br />
such as rigid cell walls or capsules, but only membranes are a<br />
universal feature <strong>of</strong> cellular life. Since its beginning, life on Earth has<br />
been associated with water. Bacteria move in water, and the<br />
metabolism inside their membranes takes place in a watery<br />
environment. In such fluid surroundings, a cell could never persist as<br />
a distinct entity without a physical barrier against free diffusion. The<br />
existence <strong>of</strong> membranes is therefore an essential condition for cellular<br />
life. 5<br />
A cell membrane is always active, opening and closing continually,<br />
keeping certain substances out and letting others in. In particular, the<br />
cell’s metabolic reactions involve a variety <strong>of</strong> ions, and the membrane,<br />
by being semi-permeable, controls their proportions and keeps them<br />
in balance. Another critical activity <strong>of</strong> the membrane is to continually<br />
pump out excessive calcium waste, so that the calcium remaining<br />
within the cell is kept at the precise, very low level required for its<br />
metabolic functions. All these activities help to maintain the cellular<br />
network as a distinct entity and protect it from harmful<br />
environmental influences. The boundaries <strong>of</strong> living networks, then,<br />
are not boundaries <strong>of</strong> separation but boundaries <strong>of</strong> identity.<br />
Social networks<br />
The main goal <strong>of</strong> my research over the past ten years has been to<br />
extend the systemic conception <strong>of</strong> life to the social domain, and in my<br />
last book, The Hidden Connections,I discuss this extension in terms <strong>of</strong><br />
a new conceptual framework that integrates life’s biological, cognitive<br />
and social dimensions. 6 My framework rests on the assumption that<br />
there is a fundamental unity to life, that different living systems<br />
exhibit similar patterns <strong>of</strong> organisation. This assumption is supported<br />
by the observation that evolution has proceeded for billions <strong>of</strong> years<br />
by using the same patterns again and again. As life evolves, these<br />
28 Demos