Eric speaks of the two kinds of electronic money systems-- closed ones where crypto doesn't have to be done because the system guarantees security, and open ones where crypto has to be used.
The closure, however, of these systems means that they don't scale. That's bad, fatal, in fact. That doesn't mean that closed systems will disappear, merely that the largest systems must be open.
What is desirable economically is that the boundary between closed clearance systems and open clearance systems be porous enough that the market can find an optimal distribution between the two varieties.
Right...I think. What has to scale is the "semantics of money." Within a small area ("box"), security is guaranteed by how the enclosing system works, and over a larger area it's done by crypto (*). But for the programs, the difference is transparent, except for a cost that resembles communications cost. (*) There's also an issue of, "Can that box over there guarantee me that I can run programs securely within it?" There are ways to do this with tamperproof boxes and such. Or looser ways to do it with reputations. -fnerd - - - - - - - - - - - - - - - nutritional information per serving: less than one (1) bit -----BEGIN PGP SIGNATURE----- Version: 2.3a aKxB8nktcBAeQHabQP/d7yhWgpGZBIoIqII8cY9nG55HYHgvt3niQCVAgUBLMs3K ui6XaCZmKH68fOWYYySKAzPkXyfYKnOlzsIjp2tPEot1Q5A3/n54PBKrUDN9tHVz 3Ch466q9EKUuDulTU6OLsilzmRvQJn0EJhzd4pht6hSnC1R3seYNhUYhoJViCcCG sRjLQs4iVVM= =9wqs -----END PGP SIGNATURE-----