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The 7% rule
fact, fiction, or misunderstanding

October 2011 | BY Philip Yaffe


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Volume 2011, Number October (2011), Pages 1-5

The 7% rule: fact, fiction, or misunderstanding
Philip Yaffe
DOI: 10.1145/2043155.2043156

In 1971, Albert Mehrabian published a book Silent Messages, in which he discussed his research on non-verbal communication. He concluded that prospects based their assessments of credibility on factors other than the words the salesperson spoke—the prospects studied assigned 55 percent of their weight to the speaker's body language and another 38 percent to the tone and music of their voice. They assigned only 7 percent of their credibility assessment to the salesperson's actual words. Over the years, this limited experiment evolved to a belief that movement and voice coaches would be more valuable to teaching successful communication than speechwriters. In fact, in 2007 Allen Weiner published So Smart But... discussing how to put this principle to work in organizations.

Phil Yaffe thinks that the 7 percent rule is a pernicious myth. He debunks the notion that in an oral presentation, what you say is considerably less important than how you say it. He rejects the claim that content accounts for only 7 percent of the success of the presentation, while 93 percent of success is attributable to non-verbal factors, i.e. body language and vocal variety. The myth arises from a gross misinterpretation of a scientific experiment. It needs to be put to rest both for the benefit of presenters and the sake of scientific integrity.

Peter J. Denning

Have you ever heard the adage that communication is only 7 percent verbal and 93 percent non-verbal, i.e. body language and vocal variety? You probably have, and if you have any sense at all, you have ignored it.

There are certain "truths" that are prima face false. And this is one of them. Asserting that what you say is the least important part of a speech insults not only the intelligence of your audience, but your own intelligence as well.

The whole objective of most speeches is to convey information, or to promote or defend a point of view. Certainly, proper vocal variety and body language can aid the process. But by their very nature, these ancillary activities can convey only emphasis or emotion.

The proof? Although today we presumably live in a visual world, most information is still promulgated in written form, where vocal variety and body language play no role. Even the "interactive" Internet is still mainly writing. The vast majority of people who surf the Internet do so looking for texts, with which they may interact via hyperlinks, but it is still essentially text.

Likewise with a speech. If your words are incapable of getting your message across, then no amount of gestures and tonal variations will do it for you. You are still obliged to carefully structure your information and look for "le mot juste" (the best words or phrases) to express what you want to say.

So just what does this "7% Rule" really mean?

The origin of this inimical adage is a misinterpretation, like the adage "the exception that proves the rule." This is something else people say without examining it. If you believe that this is actually true, I will demonstrate at the end of this article that it isn't. But first things first.

In the 1960s Professor Albert Mehrabian and colleagues at the University of California, Los Angles (UCLA), conducted studies into human communication patterns. When their results were published in professional journals in 1967, they were widely circulated across mass media in abbreviated form. Because the figures were so easy to remember, most people forgot about what they really meant. Hence, the myth that communication is only 7 percent verbal and 93 percent non-verbal was born. And we have been suffering from it ever since.

The fact is Professor Mehrabian's research had nothing to do with giving speeches, because it was based on the information that could be conveyed in a single word.

Subjects were asked to listen to a recording of a woman's voice saying the word "maybe" three different ways to convey liking, neutrality, and disliking. They were also shown photos of the woman's face conveying the same three emotions. They were then asked to guess the emotions heard in the recorded voice, seen in the photos, and both together. The result? The subjects correctly identified the emotions 50 percent more often from the photos than from the voice.

In the second study, subjects were asked to listen to nine recorded words, three meant to convey liking (honey, dear, thanks), three to convey neutrality (maybe, really, oh), and three to convey disliking (don't, brute, terrible). Each word was pronounced three different ways. When asked to guess the emotions being conveyed, it turned out that the subjects were more influenced by the tone of voice than by the words themselves.

Professor Mehrabian combined the statistical results of the two studies and came up with the now famous—and famously misused—rule that communication is only 7 percent verbal and 93 percent non-verbal. The non-verbal component was made up of body language (55 percent) and tone of voice (38 percent).

Actually, it is incorrect to call this a "rule," being the result of only two studies. Scientists usually insist on many more corroborating studies before calling anything a rule.

More to the point, Professor Mehrabian's conclusion was that for inconsistent or contradictory communications, body language and tonality may be more accurate indicators of meaning and emotions than the words themselves. However, he never intended the results to apply to normal conversation. And certainly not to speeches, which should never be inconsistent or contradictory!

So what can we learn from this research to help us become better speakers?

Basically, nothing. We must still rely on what good orators have always known. A speech that is confused and disorganized is a poor speech, no matter how well it is delivered. The essence of a good speech is what it says. This can be enhanced by vocal variety and appropriate gestures. But these are auxiliary, not primary.

Toastmasters International, a worldwide club dedicated to improving public speaking, devotes the first four chapters of its beginner's manual to organizing the speech itself, including a chapter specifically on the importance of words in conveying meaning and feeling. Only in Chapter 5 and Chapter 6 does it concern itself with body language and vocal variety.

I don't know how to quantify the relative importance of verbal to non-verbal in delivering speeches. But I have no doubt that the verbal (what you actually say) must dominate by a wide margin.

One of the most famous speeches of all time is Abraham Lincoln's "Gettysburg Address." Its 272 words continue to inspire 150 years after they were spoken. No one has the slightest idea of Lincoln's movements or voice tones.

Now, what about that other oft-quoted misconception "the exception that proves the rule?"

If you reflect for a moment, you will realize that an exception can never prove a rule; it can only disprove it. For example, what happens when someone is decapitated? He dies, right? And we know that this rule holds, because at least once in history when someone's head was chopped off, he didn't die!

The problem is not with the adage, but with the language. In old English the term "prove" meant to test, not to confirm as it does today. So the adage really means: "It is the exception that tests the rule." If there is an exception, then there is no rule, or at least the rule is not total.

Native English speakers are not alone in continuing to mouth this nonsense; in some other languages it is even worse. For example, the French actually say "the exception that confirms the rule" (l'exception qui confirme la règle), probably because it was mistranslated from English. This is quite unequivocal, leaving no room for doubt. But it is still wrong.


Philip Yaffe was born in Boston, Massachusetts, in 1942 and grew up in Los Angeles, where he graduated from the University of California with a degree in mathematics and physics. In his senior year, he was also editor-in-chief of the Daily Bruin, UCLA's daily student newspaper. He has more than 40 years of experience in journalism and international marketing communication. At various points in his career, he has been a teacher of journalism, a reporter/feature writer with The Wall Street Journal, an account executive with a major international press relations agency, European marketing communication director with two major international companies, and a founding partner of a specialized marketing communication agency in Brussels, Belgium, where he has lived since 1974. Among Yaffe's recent books are The Gettysburg Approach to Writing & Speaking like a Professional and Science for the Concerned Citizen (available from Amazon Kindle).

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Happen to be doing research and ran across your paper. Please consider deeper research, whereas you are correct when you mentioned "what you say" in a speech is important, however it alone is not the most important. Instead, consider that three parts of persuasion are equally important: that is, Logic, Credibility and Emotion. I'm sure what I read may have been misinterpreted on my part (I apologize in advance if so) but if not, you seem to have a great interest in helping speechmakers and giving others more accurate information is always desirable. Keep up the great work!

— Professor Miller Lucky, Mon, 06 Jan 2014 03:39:36 UTC

As a counter-example to Lincoln, here is the most quoted section of JFK's moon speech. "We choose to go to the moon. We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others, too." Do the other things? And the others, too? Truly stirring words. He might as well be saying "go team" based upon the actual meaning of his rhetoric. Why does it still resound then? Because it fills its purpose well, that purpose being an emotional appeal to greater achievement through unity. Looking at the words, you can tell that they aren't of primary importance. In fact, without the recording of that speech, I don't suppose it wouldn't be remembered much at all outside of its grand associations. As a leader speaking to the social mass of people, he was trying to convey nothing more than optimism. He wasn't attempting to explain a plan of action or communicate any particular concept. Not to sound too disparaging, but, while he individual may be rational and logical, the group, the human herd, responds quite strongly to all of the pre-conscious triggers and reflexes that we've inherited from our evolutionary process. I don't mean to sound like one of those "the great mob is wild and must be controlled" types from the days of Bernays, but it is true that addressing a crowd is primarily an emotional endeavor, not an informational one. It is not a presentation of data. As to the %, I agree that the study is extremely narrow and applies only to a specific circumstance. Even assigning a % to something like this is preposterous. What it does appear to show is that human judgement and confidence follows emotional lines, and that emotions are most easily expressed through non-verbal communication. As such, if you want someone to value what you say, how you say it is more important than the actual specifics. As a final thought, I might posit that 272 words, carefully chosen, seems to me not a speech. To me, that sounds very much like a poem.

— chandler, Tue, 19 Nov 2013 10:37:44 UTC

I think that it is true how mostly what people focus on is body language, tone, and other non-verbal communication.

— Com Muni Cator, Wed, 27 Feb 2013 01:21:59 UTC

thanks so much for this great help, great site! Keep it up.Will recommend this site to others. Oral Presentation

— claudia , Tue, 06 Nov 2012 09:34:36 UTC

Your article is well written, but seems rather incomplete in its examination and I would like to point out just a few concepts: I quote you "The whole objective of most speeches is to convey information, or to promote or defend a point of view" and "The essence of a good speech is what it says". The above is only part of the story, other objectives also include inspiring an audience and persuading them to align with the speakers point of view. These objectives are of primary importance. The true value of a speech is measured by how closely its effect on its audience matches its intended purpose. Even brilliantly written speeches that are poorly delivered can never be moving, meaningful or memorable to their audiences. Yet there are speakers that ramble and who are less than eloquent in their chosen words that are capable of moving great masses of people. I don't know how to measure the relative importance of words, voice tone and body language within a speech. I would suggest that it depends on the audience, the situation and the intent of the speaker. However, I would also suggest that the way in which words are used in a speech is of less relative importance than in written language, and possibly even secondary in some cases. Wikipedia has an interesting article on the subject of "Rhetoric" for further reading.

— Christiaan Dednam, Wed, 25 Jan 2012 06:31:09 UTC

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