I wholeheartedly agree with Tim that economics should play an important role in analyzing cryptographic protocols. It lets us step back and ask what features are important, and in general what we are trying to accomplish: usually something very different than the military uses of cryptography that have given rise to the current methodologies. To economics, especially game theory, I add a vast body of knowledge about human relationships, especially those involving commerce, that civilization has accumulated over the years: law, especially business law. If we step back and look at what many cypherpunks are trying to achieve, a major idealistic theme is a Ghandian cyberspace where violence can only be make-believe, whether in Mortal Komat or "flame wars". Cypherpunks want our telephone networks, Internet businesses, etc. to be both protected from force, and not dependent on force for their existence. Our 20th century information commerce systems, from publishing to credit cards, have often been very dependent on the threat of violence, usually law enforcement, to protect intellectual property rights, deter fraud, collect debts, etc. There is no utopia in sight where such threats can be completely eliminated, but we can recognize that they exist and carefully work to reduce our dependence on them. In a far more practical vein, the dawn of international commercial networks that criss-cross hundreds of jurisdictions with complex, obscure, and often contradictory regulations, gives rise to a vast market opportunity for substituting, where possible, network security mechanisms for law enforcement dependencies. The recent discoveries in cryptographic protocols provide us with a rich toolbox for solving these problems. Perhaps the most fundamental building block of business law is the contract. Strongly related to Tim's ontology of money is an area I have developed quite extensively called _smart contracts_. The terms of contractual relationships can often be formalized and standardized, and then performed via network-based protocols. These protocols, along with economic incentives, protect the performance of the contract from both fraud by the principals and attack from third parties. This is also the basic task of law enforcement in commercial law; thus smart contracts when successful reduce dependence on law enforcement as well as losses to fraud and cracking. Of special interest to cryptologists is that the principles of contract provide us with a methodology for the use of cryptography that is very different from, and potentially far more lucrative than, the traditional military paradigm. I have much more to say about these things in my essays under http://www.digicash.com/~nick/, and in a forthcoming article for _Extropy_. Nick Szabo szabo@netcom.com