Re: SUO: -- Technical Methodology
Dear Matthew,
Just one qualification:
> MW: Petri nets deal with classes of activity/process
> rather than particular ones, so they deal with valid
> patterns of activity which will be atemporal.
It is true that a Petri net, as a specification, is
atemporal. But a Petri net marked with tokens that are
in the process of "firing" exists in space and time.
The main point I wanted to make is that the processes
created by the firing of the transitions in a Petri net
are defined in a way that makes no reference to either
space or time.
They exist in space-time, but they do not depend on any
metric for space or time. In fact, I would prefer to
say that metric time is a convention that is defined by
a clock, which can be specified by a suitably designed
Petri net. That way of talking makes causal dependency
more fundamental to the ontology than temporal precedence.
John