Whether they're placed in retail stores, libraries, waiting rooms or corporate lobbies, digital signs generally have to accomplish one of two things: inform the audience, or persuade the audience to take action. In the past, we've spent a lot of time looking at how to make digital signage content that informs, studying things like making the content as comprehensible and memorable as possible, and creating minimalist messages that get the point across in the first few seconds before a viewer's attention starts to fade. And when it comes to purely informational content, those are the most important things. However, when the goal of the content is not merely to inform but also to persuade, that brief message not only has to inform, but must also make an appeal to the viewer. Despite a good, solid century of effort by the advertising industry, we've yet to find an effective path to persuasion that doesn't stem from one of the three modes that Aristotle denoted some 2,300 years ago: ethos, pathos and logos.

Ethos: What Would Oprah Do?

According to Wikipedia, "Ethos is an appeal to the authority or honesty of the speaker. It is how well the speaker convinces the audience that he or she is qualified to speak on the particular subject." Simply put, we tend to believe people that we respect, which is why the ideas of many so-called "experts" persist even after they've been debunked. Ethos almost certainly fueled Activia's choice of Jamie Lee Curtis as spokesperson: she's recognizable and generally well-regarded, and has made graceful aging her "brand" for the past several years. It's also the reason why Donald Trump was a good choice for the boss in The Apprentice. The show's producers were no doubt attracted by the TV-worthiness of his insane rants and lamentable hairstyle. But besides the pure entertainment value, viewers and contestants are likely to view the Trump "brand" as being synonymous with making money. The Donald convincingly commanded authority because -- love him or hate him -- he made himself rich.

In the world of digital signage -- and particularly in high-traffic environments like retail stores -- using ethos to help persuade your viewers is really, really hard. Unless your content actually features somebody both identifiable and well-respected in your field, you simply aren't going to have enough time to introduce your argument-maker, establish him as a reputable, respectable and noteworthy expert, and have him deliver your argument to the viewer. Heck, most infomercials can't even get this done in a 30-minute spot. How somebody might think they'd do it in a 30-second spot (of which a viewer might only see 3 seconds or less) is beyond me.

Pathos: What FUD was called back in 300 B.C.

Pathos is an appeal to your audience's emotions, whether positive or negative. It's when you make a statement about some value (e.g. "big government is bad") in hopes that it will reflect your audience's own perception of that value. Real-world examples? Remember those "I've fallen, and I can't get up!" commercials? Classic example of pathos. While fear and uncertainty are definitely the low-hanging fruit for producers working on pathos-driven content, positive emotions work equally well. It's the reason why everything gets decked out in red, white and blue around the 4th of July in the US (patriotism). Or why retailers start piping in Christmas music in December November October (nostalgia, or if you're a kid, toys).

There are a number of convincing ways to use pathos in digital signage content. For one, it's an appeal that lends itself well to imagery. If you're putting together a spot advertising the availability of the flu shot, add in a picture of a crying baby to induce feelings of responsibility and compassion, while using text to make the argument that neither you nor your children want to get the flu or give it to others.

There are also some text tricks that can help convey pathos. For example, it's common to use simile and metaphor when making an impassioned argument. I'd recommend skipping metaphor, since unless it's a very common metaphor, it might be misconstrued by your viewers. But similes are fair game in my book. So saying that the exhaust from your new hydrogen-powered car is "as clean and clear as spring water" and coupling that with the appropriate imagery will impart more pathos than the image alone would. Whether this would be more or less effective depends on how important the particular value is to the viewer.

Logos: Or, how to overestimate your audience

If all it took to win new customers was sound reasoning and a cogent, logical argument, I'd be sitting on a beach somewhere waiting for my manservant to bring my morning libation in a coconut. OK, probably not, but you get the picture. We all love to pretend that the average person is a rational being, but when it comes to advertising, logos is almost never enough. If it were, all ads would consist of a few lines of black text on a white background, and agency creative departments would look more like the accounting department and less like... well... have you seen what agency creative departments look like?

Now, that's not to say that your advertising copy shouldn't make a measured, logical appeal. We know that explanations of how products save time and money are some of the most effective out there, and we also know that most viewers respond well to simple statistics (e.g. "2 out of 3 plumbers recommend PipeClear!"). But because content on digital signs is typically seen for only a brief amount of time, logical arguments must be very basic, very clear, and very short to guarantee viewers see them in their entirety. Additionally, they work best when based on information and premises that the viewer is already familiar with, since transmitting new information takes valuable viewing and comprehension time. In short, a logical argument is most effective when it reiterates or reinforces an argument that was already made elsewhere.

Much like creating effective digital signage content, being persuasive requires both science and art. And it certainly takes a lot of practice. Yet for all the effort that content producers put into making clips that are pleasing to the eye, much less time is spent making those clips persuasive. (Big brands tend to be the exception, but let's face it, most digital signage content is not provided by the big brands.) Given that ethos, pathos and logos account for just about every form of persuasion that one might find in an ad, it follows that brands, networks and content creators are already using these tools in their ad campaigns. But if they thought about these things in the context of digital signage, the decisions on when, where and how to use each form would be considerably different than they are today. And that would lead to better, more effective and more persuasive content on screen.

What's the key to making persuasive digital signage content? Text? Imagery? Sound? Something else? Leave a comment and let us know what you think.