> Generally speaking, "the value of a graph is proportional to the square of the number of edges"
No, what Metcalfe's law assumes is that the value of the graph is proportional to the number of edges (not their square). And from that assumption and the fact that the graph is fully connected follows that it's proportional to the square of the number of nodes. (Because you can have (n-1)*n/2 edges with n nodes in a fully connected graph.
And hence, the Reiser quote above is similar but it emphasizes something else: it states what Metcalfe's law (I think) uses as a premise (or implicit claim) that the value is in the connections. Because it's not necessarily a fully connected graph.
Edit: originally I've given (n-1)*2/2 as the number of edges instead of (n-1)*n/2.
No, what Metcalfe's law assumes is that the value of the graph is proportional to the number of edges (not their square). And from that assumption and the fact that the graph is fully connected follows that it's proportional to the square of the number of nodes. (Because you can have (n-1)*n/2 edges with n nodes in a fully connected graph.
And hence, the Reiser quote above is similar but it emphasizes something else: it states what Metcalfe's law (I think) uses as a premise (or implicit claim) that the value is in the connections. Because it's not necessarily a fully connected graph.
Edit: originally I've given (n-1)*2/2 as the number of edges instead of (n-1)*n/2.