The Ancient Greeks posited three keys to persuasion– logos, aka logic, pathos, aka emotion, and ethos, aka personal character or credibility.
Of the three, the most important is ethos. All the logical and emotional appeals mean nothing if the speaker has no credibility.
So let’s talk about how to boost credibility and persuasiveness for your presentations and meetings.
Build a relationship prior to the pitch. I worked recently with a construction firm competing for the chance to build a prison for a south Georgia county. The same team had recently built a hospital for the county. They had strong relationships with the key decision-makers.  As a result, the team came to that pitch with an enormous amount of credibility and eventually won.
You can build similar credibility before almost any presentation. Let’s say that you’re trying to persuade a committee to approve your budget. Rather than show up and try to persuade with raw logic, build your credibility first by forming relationships with the decision-makers.
Make appointments to talk with the committee members before the final “pitch.†During those appointments, you’ll presell your ideas and shape your message to meet their needs. You’ll also build relationships that will boost your credibility.
Dump the notes and make better eye contact. If you’re reading your notes, you’re not making good eye contact. That undermines your credibility.
Many studies link eye contact and credibility.  I recently read a study from the 1970s conducted at the University of Missouri. The study compared a speech that was both read to an audience and delivered without notes. The listeners found the speaker without notes to be more credible. The listeners also retained more information from the speaker that didn’t read the speech.
Of course, we don’t need a study to convince us that eye contact builds credibility.   When I ask my daughter whether she’s done her homework, I listen to what she says. I also watch her eyes.
Take lots of Questions. I once helped a company create presentations to be delivered to employees of manufacturing plants that were closing down. The managers wanted to tell the frightened and angry employees about their options.
The presentations were successful.  But the key wasn’t the formal “PowerPoint.â€Â Rather, the managers won credibility points by making it clear that they would take as many questions as needed. One presenter said, “If we have to, we’ll stay until two in the morning to answer all your questions.â€
A willingness to take questions shows an openness that makes your audience believe in you.
Give tight answers. A short answer is usually more credible than a longer answer.
Here are two answers to the question “How much will it cost?â€
Bad answer: “How much it costs depends on how much time we put in. And how much time we put in depends on how fast we can get the information from the client. Right now we don’t have a good sense of how much time that will take. But I’m guessing the cost will be $50,000.
Good answer:Â We estimate it will cost $50,000. That could vary depending on issues of timing and information availability.
The good answer makes the speaker sound confident.
The Ancient Greeks understood that you can’t persuade without a strong ethos. It’s a lesson we should remember in modern times.