The value of a message [...] appears to reside not in its information (its
absolutely unpredictable parts), nor in its obvious redundancy (verbatim
repetitions, unequal digit frequencies), but rather in what may be called its
buried redundancy - parts predictable only with difficulty, things the
receiver could in principle have figured out without being told, by only as
considerable cost in money, time or computation. In other words, the value of
a message is the amount of mathematical or other work plausibly done by its
originator, which the receiver is saved from having to repeat.10
...this means [that] we use digital computers whose architecture is given
to us in the form of a physical piece of machinery, with all its artificial
constraints. We must reduce a continuous algorithmic description to one
codable on a device whose fundamental operations are countable, and we do this
by various forms of chopping into pieces, usually called discretization. [...]
The compiler then further reduces this model to a binary form determined
largely by machine constraints.
The outcome is a discrete and synthetic microworld image of the original
problem, whose structure is arbitrarily fixed by a differencing scheme and
computational architecture chosen at random. the only remnant of the continuum
is the use of radix arithmetic, which has the property of weighing bits
unequally, and for nonlinear systems is the source of spurious singularities.
This is what we actually do when we compute up a model of the physical world
with physical devices. this is not the idealized and sere process that we
imagine when usually arguing about the fundamental structures of computation,
and very far from Turing machines.14