Forty (2000) points out that every cultural endeavor has been claimed as a language at one point or another–film, painting, music, sculpture, fashion, etc. He points out that there are a number of gradations in the comparison between architecture and language.
First, there is the difference between is and like–that architecture is like a language in that it has meaning as well as components that are systematically joined, verses architecture is in fact a language, with all the features thereof.
There is a difference between carrying meaning and having a syntax; the two, as shown by Langer’s presentational forms, are not necessarily synonymous. And there is a difference between seeing architecture as literature–a completed composition within a language–and seeing architecture as linguistic–a generative form of communication.
Forty also reviews the historical motivations for claiming that architecture is a language. One is that it discourages invention. Just as an eloquent speaker does not coin new words for every use but creatively combines the existing symbols within the syntactic rules, so should an architect follow the conventions of his day.
A second motivation is that it places architecture in the realm of art, rather than simple utility. Architecture can be like poetry or literature, and so carry such attributes as character, style, rhythm, and truth.
A third is to describe the origins of architecture–to claim, just as in language, it is more useful to discover the rules of generation than to dogmatically trace and emulate the historical root
A fourth is that it proves architecture communicates. Victor Hugo felt that buildings could be read as texts, and that Gothic architecture was the most complete and permanent form of social record until being replaced by the book.
A fifth motivation is, as we’ve seen, to show that architecture is an ordered system, like a grammar. Finally, if architecture is a full-fledged semiotic system, then it carries meaning.
It is helpful to realize is that language is certainly not the only metaphor used to illustrate architecture. Forty also cites a number of science metaphors. One is that of the human circulation system, There is also a high incidence of terms from both static and fluid mechanics used to describe the appearance architecture. These terms include tension, stress, compression, torsion, shear, equilibrium, centrifugal, and centripetal.