Pictures are powerful. Single images have defined generations and persuaded thousands of people to action. Yet even in the formal study of rhetoric there is comparatively little to say about visual persuasion.
Meanwhile pictures are getting bigger. Sometimes literally, in the case of social media and digital communities, but also in the sense of their importance. We see hundreds of persuasive images a day. Some we notice, most we don’t. A select few capture our attention and may even convince us to do something—buy a bike, exercise, donate to a cause, etc.
If we are to be better rhetors, we need to have at least a basic understanding of the principles of visual communication and persuasion.
Let’s have a look…
Principle 1: Pictures Are Not Reality
All images, even photographs, are representational. They are selections or a re-creations of reality. Just as it’s impossible for an author to explain everything about a subject in a blog post, a speech, or even a book, it’s equally impossible for a visual author to present the entire world in a single image or series of images. The author must choose what he wants you to see. These choices are important. They tell you a lot about the intended message.
Principle 2: What’s Missing Is Important
When examining persuasive images, it’s as important to analyze what was left out of the picture as it is to examine what was put in. This can only be done when comparing the image to reality. What’s highlighted and what’s missing? What’s the best explanation for the author leaving it out?
Principle 3: Metaphors Galore
Because they are representational, images rely heavily on metaphor for persuasion—since it’s relatively easy to reconstruct reality in a symbolic way. As an example, look at the now infamous picture of two burning cigarettes in place of the World Trade Center towers. It’s a powerful (controversial) message to say that smoking shares certain attributes with 9/11 (primarily a high body count). This leads in to the next principle…
Principle 4: Worth 1000 Emotions
Text can make complex logical arguments. It can sustain a point over paragraphs and pages. An image is a single rhetorical entity. Sure pictures can have multiple or intricate parts or be one in a series, but for the most part they are standalone, individual entities. (This does not apply to infographics, of course, but they’re another topic entirely.) As a result the primary appeal of a picture is emotion. They can make you recall an emotional association or create a new association through metaphor. Don’t feel bad for images because they lack the ability to make logical arguments. The reason images are so powerful is precisely because of their emotional appeal.
* * * * *
These principles are by no means exhaustive, but they are a great start in your study of visual rhetoric. Master them and you’re on your way to becoming a better rhetor. You’ll see.