Since no one ever accomplishes anything truly worthwhile on their own, every successful person I know is really good at persuading and influencing other people. (Not as an influencer, but as a formal and informal leader.)

Being persuasive means being convincing, which means sounding intelligent, since few people pay attention to people they don’t think are intelligent.

So yeah: if you want to be more persuasive, if you want to be able to influence the people around you, then you need to sound intelligent.

One easy way? Just speak a little faster.

According to a study published in Language and Speech, how people perceive your competence level increases as your speech rate increases. (As long as you don’t sound like you just slammed three Red Bulls.) Similar findings come from a study published in Journal of Nonverbal Behavior: moderately faster speech is linked to greater confidence, competence, and credibility.

Makes sense: rattling things off (think Noah Wylie in The Pitt) and you seem smart, credible, confident, and competent.

Yet speaking at a measured pace can also be a sign of confidence. (Think James Spader in, well, basically every role he’s ever played.) Rapid speech can imply certainty. But so can measured speech.

So what should you do? There’s a better approach than simply speaking quickly or slowly, since how quickly you should speak can depend on the situation you’re in.

A study published in Educational Psychology suggests:

If your audience is likely to disagree, speak a little faster.
If your audience is likely to agree, speak a little slower.

Why? When your audience is inclined to disagree with you, speaking faster gives them less time to form their own counterarguments, which gives you a better chance of persuading them.

When your audience is inclined to agree with you, speaking slowly gives them time to evaluate your arguments and factor in a few of their own thoughts. The combination of your reasoning and their initial bias means they are more likely to actually help persuade themselves.

Bottom line? If you’re preaching to the choir, speak a little slower. If you’re not, speak a little more quickly. And if your audience is neutral or apathetic, speak a little more quickly so you’ll be less likely to lose their attention.

But no matter what you do, think about your rate of speech.

Because when you need to seem more intelligent or more convincing, what you say matters, but so does how quickly, or not, you say it.