1. Visual Rhetoric and Media
Medium
the channel by which information is expressed, collected, stored, and/or circulated

2. Four Points
(Visual) Media are material and thus, like modes, offer an array of affordances
(Visual) Media are cultural in that their materiality and their operations (their affordances, if you will) are embedded within a set of cultural discourses regarding their value and use.
(Visual) Media have permeable boundaries, overlapping within the circulation of a single artifact.
(Visual) Media operate ecologically to form a taken-for-granted media reality (i.e., a soundscape or a vision-scape).
So how do these four points implicate visual rhetoric?

3. Birmingham, AL, 1963 Bill Hudson, AP photojournalist
Bill Mauldin, published in the St. Louis Post-Dispatch, May 15, 1962.
Maya Lin, Artist and Architect

4. Point 1: (Visual) Media are material Media Specific Analysis
A mode of critical attention which recognizes that all texts are instantiated and that the nature of the medium in which they are instantiated matters.
The materiality of those embodiments interacts dynamically with linguistic, rhetorical, and literary practices to create the effects we call literature [visual rhetoric] (69-70, emphasis added ).
(N. Katherine Hayles, “Print is Flat, Code Is Deep: The Importance of Media Specific Analysis”)

5. MSA Methodology
Step 1: Identifying media constraints:
Media differ profoundly in their physical properties and dynamic processes (71), so the first step is to identify the nature of their material affordances.
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6. Step 2: Tracing across a single “term”:
The power of MSA comes from holding one term constant and then varying the media to explore how medium-specific constraints and possibilities shape texts.
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7. Step 3: Identifying the differences in media constraints that make a difference
In emphasizing materiality, I [this is Hayles talking] do not mean to imply that all aspects of a medium's apparatus will be equally important. Rather, materiality should be understood as existing in complex dynamic interplay with content, coming into focus or fading into the background, depending on what performances the work enacts. . . It is not merely an inert collection of physical properties but a dynamic quality that emerges from the interplay between the text as a physical artifact, its conceptual content, and the interpretive activities of readers and writers. (emphasis added)
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8. So the key question to address is as follows:
What distinguishes visual rhetoric instantiated in one form from visual rhetoric in another form?
But wait: there is more!

9. Point 2: (Visual) Media’s materiality is framed discursively
If media are (material) channels by which information is expressed, collected, stored, and/or circulated, then they are material channels that come with cultural baggage. They are bounded causal agents.
Melinda Turnley in "Towards a Mediological Method: A Framework for Critically Engaging Dimensions of a Medium“ draws on Jules Regis Debray’s theory of mediology to make this very point.

10. mediology: emphasizes intersection of praxis and ideology across seven dimensions: technological/material, social, economic, archival, aesthetic, subjective, and epistemological
Paraphrasing Debray, Turnley argues:
"Rather than positioning media as causal agents that have automatic influence [i.e., material agency], mediology assumes a co-constructive relationship between medium and milieu. A milieu sets horizons of meaning and logics of use," which includes supporting “certain systems of power and access” (128).
In other words, mediology invites us to ask what cultural discourses swirl around a medium that function to orient cultural citizens to use and respond to a medium in a particular way, to assign it a value that reflects its positions within organizational and cultural hierarchies.

11. Bottom line, as a “vectors of culture,” media and their operations exist in a co-constitutive relationship with larger historical and social structures. Media, then, are important not just because of their materiality but also because of the transaction between that materiality and a medium’s milieu. In other words, what cultural citizens believe about a medium implicates what they do with that medium.
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But wait. There is even more.

12. Point 3: (Visual) Media have permeable boundaries.
Hayles notes that the material features of a medium cannot be clearly demarcated from the users’ signifying practices. Similarly, Debray contends that medium and its materiality cannot be separated from cultural, political, economic, aesthetic (and other) discourses. So both emphasize the permeability or contingency of medium, including its materiality.
But media also have permeable boundaries in their performance, a permeability that complicates media specific analysis and mediology. Media tend to transact in performance. I’m not just talking here about multimedia texts, although that does complicate media’s materiality and its cultural discourses. I am talking about the embedding of media within media, a kind of expansion of I. A. Richards’s notion of context.
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13. Point 4: (Visual) Media operate ecologically, forming both a background and a repertoire—an everyday archive, if you will—of habits/attitudes and resources.
We know from Harry Jenkins and others about media convergence. And we know from Postman and others about media ecologies, or “the ways in which the interaction between media and human beings gives a culture its character” (62). However, I am pointing to something more subtle, perhaps more basic: the ways in which media, especially visual media, conspire to form an ambient environment, or a “landscape” [soundscape, vision-scape, bodyscape], replete with attitudes toward the medium as well as resources of the medium.
James Marcum refers to a visual media ecology as as “a comprehensive participatory event, a universe of action, and a world of knowledge and learning” (189), one that yields what he calls an action-perception cycle. It is this action-perception cycle that the concept of “ambient visual media ecology” [my term] gets at.
Not to mix metaphors, it is the sea we swim in and the fish that we eat. As such, it holds implications for visual rhetoric.
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