I think the answer to this question may be in the OED, but I don't have access to the service. I am discussing "texts" using definitions (from dictionary.com) like this:
text: any theme or topic; subject.
text: anything considered to be a subject for analysis by or as if by methods of literary criticism.
Within the context of cultural anthropology I'm having a discussion with my students about how the definition of a text has expanded over the years to include not just texts comprising words but also visuals (e.g., images in advertisements).
I've come across the latter usage of text in certain educational books:
"Like written texts, visual texts have been carefully constructed by their composers to shape meaning, and to affect and influence the viewer."
"This resource covers how to write a rhetorical analysis essay of primarily visual texts with a focus on demonstrating the author’s understanding of the rhetorical situation and design principles."
An ngram search for "visual texts" doesn't have many results before the 1960s, and some of the results refer to visual texts in single or double quotes to highlight the non-standard usage.
My question is:
- Since dictionaries are formally acknowledging that a text need not be comprised of words only, when did the concept of a 'visual text' become a subject of analysis in its own right?" (e.g., the MacIntosh logo of an apple; see http://creativebits.org/interview/interview_rob_janoff_designer_apple_logo)