A successful persuasive message depends not only on what you say but on where you say it. Strategically positioning your best information is important.
In most cases, if you are advocating one position over another and you have a strong argument, or if you have ion, such as a good idea and supporting details, you should position it first. Many people will say position it last because people remember the last thing they read, but psychologists have found that that is true only in limited circumstances. Positioning depends primarily on the nature of your audience.
People process persuasive messages differently, depending on whether they are a “motivated” or an “unmotivated” audience, according to a model designed by psychologists Robert Petty and John Cacioppo.
These people are interested in the message because the information is relevant to them. Perhaps they are part of the decision making, or maybe they could be affected by the outcome. These readers are attentive from the start and will read the message closely, analyze it, consider whether it fits with their existing knowledge, and form an opinion. If you present a strong case in your opening few paragraphs, they are likely to embrace that position, and they tend to pay less attention to, and are less likely to accept, subsequent arguments in the message.
Most of the time, your persuasive appeals will be to motivated audiences.
Occasionally, you will need to persuade an unmotivated audience, that is, people who are only marginally interested, either because the message has little relevance to them or because they are apathetic. Social psychologists found that these readers do not read closely until part way through the message, when something suddenly draws their attention. These readers are more likely to remember the last thing they read.
Using a decoy
If you want to make your preferred option look even better than it is, create a third option, one that you know the reader will surely reject because it is so unappealing. Insert this so-called decoy between options A and B.
The contrast principle in persuasion says that we evaluate things in the context of what we just experienced. That’s why, if you take your hand out of ice cold water and put it in room-temperature water, that water will seem quite warm, even though it is only room-temperature.
Once the reader reads your first option and then contrasts that with one that is strikingly unappealing, the first option looks even more impressive than it actually is.