Why is persuasion the world's most researched skill? That's easy-as history shows, it's the world's most important skill!

Take a trip back to the Fifth Century B.C., when Athenians were experimenting with a new form of government. The Athenians quickly discovered that to succeed in a democracy, they had to be persuasive. Leaders used persuasion (then called rhetoric) to gain agreement and win support. Everyday citizens used persuasion before a new legal body-the jury.

Recognizing its importance, Athenian scholars, including Plato and Aristotle, began to study the powerful process of persuasion. Circa 435 B.C., they defined three elements of the process of persuasion: Logos, the appeal to logic, reason, and facts; Pathos, the appeal to emotions; and Ethos, the appeal of the speaker's character and credibility. These scholars found that one or more of these appeals characterize any instance of persuasion. Aristotle wrote three books about persuasion.

Among his conclusions, he stated that logic is the most reliable appeal, and that it is a "human failing" that people sometimes tend to be persuaded less by logic and more by emotion. Scientists are now learning precisely why appeals to logic can be so unproductive. And they've learned that Aristotle had it all backward when he defined logic as the most reliable appeal to persuasion. In ancient Greece, persuasion proved to be enormously effective in politics, commerce, jurisprudence and everyday life-so much so, that when the Romans conquered Greece, they continued to study and apply the skill of persuasion. Caesar Augustus became a master persuader. He magnificently used the Ethos appeal, starting every speech with the phrase "Vini, Vidi, Vici." I came, I saw, I conquered. By establishing who he was and why people should listen to him, he was able to quickly win their support.

Fast forward to the U.S.A. in 1940s and '50s. Explosive post-war economic growth led to more research into how people could make good things happen through others. Writers produced a spate of books based on the groundbreaking research of Carl I. Hovland of Yale University. Many other prestigious universities and business schools also initiated research into the science, art and skill of persuasion. The race for knowledge on how to gain agreement, compliance, to get to YES was on in earnest!

Politicians of that era also realized that the greatest power in the world was the power to persuade. Even President Harry Truman understood how central persuasion was to his ability to lead. "I sit here all day trying to persuade people," he said. "That's all the powers of the President amount to." Today Condoleezza Rice adds to this from her own position of power, "Power is nothing unless you can turn it into influence."

In time, new and exciting facts about persuasion continued to appear. In the 1980s, Dr. Robert Cialdini, Arizona State University's Regents Professor of Psychology, conducted extensive research into the emotional "triggers" of persuasion. By the late 90s, his book, Influence - the Psychology of Persuasion, had become Amazon.com's best-selling business book. Soon, Harvard Business School and other leading institutions were offering executive courses in persuasion skills.

Today the quest for persuasion knowledge continues at warp speed. While some scientists are unraveling the human genome, defining how our chromosomes and DNA affect our physical bodies, others are unraveling the secrets of the brain, exploring how it processes decision-making information.

In this vein, Jay Conger, Director of the Leadership Institute at the University of Southern California School of Business, tells us why research into the "how to" of persuasion is so critical: "Today's business contingencies make persuasion more necessary than ever," he says. "Many businesspeople misunderstand persuasion and more still underutilize it."

The art and science of persuasion continues to attract the world's best minds. Why? Because today's leaders need to know:

• How do I motivate others to act?
• How do I produce agreement, compliance, and results?
• How do I generate change?
• How do I make important things happen with and through others?
• How do I sell my ideas, my products, and my services?
• How do I trigger YES?

The brilliant minds of antiquity had many answers, and today's scientists have even more. According to New York University Neuroscientist Joseph LeDoux, "The amygdale [the emotional part of the brain] has a greater influence on the cortex [the thinking part] than the cortex has on the amygdale, allowing emotion to dominate and control thinking."

Similarly, the book and the PBS series "The Secret Life of the Brain" (funded principally by the National Science Foundation) distills the entire 2,500 years of persuasion research into a single sentence:

"We are not thinking machines. We are feeling machines that think."

History and modern science agree. To persuade successfully, we must appeal to the listener's inborn, hard-wired need to satisfy emotional needs and wants. We must frame our presentations to appeal to specific shortcuts, the triggers embedded in each of our brains. We must learn to work with the other person's brain rather than against it as we have been doing for 2,500 years.

The brilliant minds of Greece and Rome recognized the need for persuasion, and set forth fundamental guidelines. Today's scientists and researchers have defined the specific process that our brains use to make decisions. For the first time, we understand how to work with, not against, the brain's decision-making process to help others make easy, non-analytical, yet correct decisions.

Today persuasion is more critical than ever. And for the first time we are learning how to persuade efficiently. For the first time we can see, in vivo, in real time, the brain's blood, oxygen and neuron flows as it responds to decision stimuli. We can see distinct brain elements "light up" as they are brought into play. The exciting news is that we finally understand the persuasion process, a process we've been doing poorly for 2,500 years. And that understanding enables us to produce YES, agreement, action and results with and through others.

For the first time in history, we have the scientifically documented breakthrough to quickly, easily produce YES, and the results we want and need from others.

Russ Granger, president of ProEd Corporation, is the author of The 7 Triggers to Yes!, and is an international consultant, trainer and author.