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Internal semantics and external semantics

It might be useful to call the first "internal semantics" and the second "external semantics". The internal semantics will be concerned with manipulation of symbolic structures in the machine. These, like the external programming language, will have a SYNTAX, i.e. there will be rules specifying which structures can be built and how they can be manipulated. And these internal structures may themselves have a semantics, insofar as they refer to things in the world.

In that case programs have a syntax and internal and external semantics. The internal structures are the internal semantics of the programs, but they too have a syntax and an external semantics.

Generally a programming language is defined in terms of its syntax and its internal semantics. It's up to the user to determine how to give it an external semantics, by applying the language to different sorts of problems.



Aaron Sloman
Fri Jan 2 03:17:44 GMT 1998