A Linear Taxonomy Of Types Of System-&-Process

Halliday & Matthiessen (1999: 507):

We are treating language as a semiotic system, and it may be helpful to locate this concept within the context of the history of ideas, albeit in a very sketchy fashion. As we conceive of it, the term "semiotic" is framed within a linear taxonomy of "physical — biological — social — semiotic"; and the term "system" is a shortened form of "system-&-process", there being no single word that encapsulates both the synoptic and the dynamic perspectives (we have referred to the term "climatic system" with the same observation on how it is to be understood).