In Search of Genuine DigiCash

[hughes@ah.com (Eric Hughes)]

   It's the behavior of the financial instrument I'm talking about. At some
   point, the principal goes away and has to be called from wherever it is (a
   bank account, the money market, etc.) to meet a cashed-out piece of
   digicash. In the meantime it earns interest. Thus it has principal, and
   interest, and it is called.  It's a callable bond.

Now, consider a promissory note which is redeemable on demand and
which pays interest at redemption.  This instrument has the same
financial properties as a callable bond.

Pop Quiz: why is this promissory note _not_ actually a callable bond?

Eric