A new study published in the journal Social Psychological and Personality Science provides evidence that the speed at which people speak is closely related to how polite they are trying to be. This finding suggests that people tend to speak slower when they want to sound polite, and naturally perceive others’ slower speech as more formal and polite. These insights provide a deeper understanding of how subtle voice changes can help navigate everyday social interactions.
Human interactions are full of unspoken rules about how to properly communicate. When deciding how to address someone, people don’t just choose a certain vocabulary. It also changes how the words are physically delivered, such as the volume, pitch, and speed of the words. These nonverbal aspects of communication provide a rich layer of social information.
Prominent theories of human communication suggest that politeness is used to overcome three major social factors. These factors include the social status of the listener, the level of burden the message places on that listener, and the social distance between the speaker and the listener. Social distance refers to how well two people know each other, such as the difference between close friends and strangers.
For example, asking someone for a big favor means a heavier burden than asking for a little time. This heavy burden usually requires a more gentle approach. Similarly, when talking to your boss, there is a different status relationship than when talking to a co-worker, and your language tends to be more polite.
Previous research has investigated how pitch and volume relate to politeness, but little was known about the specific role of speech rate. Nira Liberman, a professor at Tel Aviv University’s School of Psychological Sciences, and her colleagues suspected that there was an inherent link between slowness and politeness. Speaking slowly can signal that you acknowledge the other person’s higher status by demonstrating a willingness to expend more physical and mental effort into the conversation.
“Elena Stefan and I have a long-standing project about the relationship between civility and psychological distance,” Liberman said. “We believe that people use politeness to signal and create social distance and social proximity.” Psychological distance describes how far something feels from our immediate reality, and social distance is just one specific type of this broader concept.
“We also know that social distance is inherently tied not only to abstractness, but also to other psychological distances, temporal distances, spatial distances, hypotheticalities,” Liberman added. Temporal and spatial distance refers to how far apart something is in time or physical location. Hypotheticality describes how real or imaginary a scenario is, while abstraction involves thinking about the big picture rather than specific details.
“Recently, we’ve found that slowness and fastness map psychological distance and abstraction,” Liberman explained. “This naturally led to the question of whether politeness is slow or fast. Do people speak slower when they want to be more polite? Do they interpret slower speaking as more polite and faster speaking as more rude?”
To explore these questions, the researchers designed a series of four experiments to see whether people implicitly associate slow speaking with formal politeness. In the first experiment, the researchers recruited 102 Hebrew-speaking adults and asked them to listen to short audio clips. All audio messages were in Finnish. Since the participants did not understand Finnish, they had to rely entirely on the sound of the voice rather than the actual meaning of the words.
Scientists used a special software program to change the speed of a single audio message without changing its pitch. They created paired audio clips where one version was slightly slower and the other version was slightly faster than the original. For example, slow clips played at 86 to 92 percent of their original speed, and fast clips played at 112 to 122 percent of their original speed.
Participants listened to two clips and were asked to categorize them. I had to drag and drop each audio clip into a box labeled Polite and Formal or Casual and Informal. The scientists found that participants classified slow audio clips as polite and fast audio clips as casual 75% of the time.
This provides evidence that people associate a slow speaking pace with formal politeness, even when the language being spoken is incomprehensible. So the researchers wanted to find out whether the intention to be polite actually changes the rate at which a person speaks. They recruited English-speaking participants for the next stage of the study through an online platform called Prolific.
In the second experiment, 100 participants read a scenario in which they had to approach a stranger to ask a small favor. Half of the participants were asked to imagine speaking politely and formally. The other half were asked to imagine speaking in a casual, informal manner.
Participants were given a document stating this request and asked to read it aloud. They were then asked hypothetical questions. Researchers asked people if they had to say the exact same thing in the opposite style, would they speak faster or slower?
They found that 80% of people intend to speak slower when aiming for politeness and faster when aiming for a casual tone. A follow-up study with 94 different participants replicated this exact setup, but gave people a third choice. Participants can specify that their pace never changes.
Using this third option, 63% of the responses were still consistent with the researchers’ hypothesis. The results show that there is a strong association between intended politeness and intended slow speaking rate. However, these first three studies only measured awareness and self-reported intentions.
Researchers were initially unsure whether the experiment would yield significant results. “I had no idea that people used the pace of speech to decipher politeness,” Liberman told SciPost. “So we started with a relatively cursory study, thinking that if we didn’t get results, we would abandon the project.”
“We gradually moved toward more subtle procedures, such as studies in which people were asked to say fixed texts more or less politely, and studies in which they measured the rate at which they spoke,” Liberman continued. “In this latter study, we did not address pace of speaking or make it an explicit dimension in any way.”
In this final experiment, the researchers recruited 73 Hebrew-speaking women and recorded their actual conversational behavior in real time. The researchers chose to include only women. This is because previous research suggests that men and women tend to have different natural conversational paces. By focusing on one group, they hoped to keep their baseline measurements as consistent as possible.
Participants were given a specific script asking a stranger to complete an introductory questionnaire. They were randomly assigned to read the script politely or casually into a voice recorder. Importantly, the scripts written were completely identical for both groups.
The difference in recording time is entirely due to the speed of speaking, not the addition of extra polite words such as “please” or hesitation markers such as “umm”. The researchers measured the exact time elapsed between the first and last sound of each participant’s audio file.
Recordings for the polite group lasted an average of 29.66 seconds. The average recording time for the casual group was 27.94 seconds. This statistically significant difference suggests that when people try to be polite, they naturally slow down their physical speech rate. This effect appears to occur spontaneously, as the study instructions do not explicitly mention anything about speech rate.
“We use subtle cues to adjust our social distance; we move people closer or further away from us, and we feel warmer or colder toward them,” Liberman explained. “Pace of speech is one of those cues. People probably use it unconsciously, but this cue definitely seems to be deciphered.”
There are some potential limitations to be aware of. In the first study, researchers only tested some natural speaking rates. If you slow down your recording too much, the listener may not perceive it as polite. Previous research in Japanese suggests that politeness ratings increase when spoken language slows down to a certain point, but politeness ratings decrease when spoken language slows down unnaturally.
“A major limitation is that we did not examine cross-cultural effects,” Liberman noted. “We’re really interested in conducting these studies in different cultures.” Expanding the study to include men and people from a wider range of ages and regions would help reveal the universality of the effects.
Scientists hope to further investigate the exact psychological mechanisms behind this phenomenon around the world. “We want to conduct a cross-cultural study. We want to examine a more fundamental idea than the pace of speech: that in all cultures, politeness as a signal of social distance is expressed through temporal distance, spatial distance, increased hypotheticality, and abstraction,” Liberman said. “This is a big claim, as it suggests cultural-linguistic “universality.”
Liberman also invited outside perspectives to advance the project. “We welcome comments and opinions on diverse cultures,” she added. Future research could also investigate how these conversational dynamics change when individuals expect to interact with close friends, who naturally tend to be more casual.
The study, “The Association between Speech Speed and Politeness,” was authored by Ravit Nussinson, Chen Dahbash, Ayelet Hatzek, Elena Stephan, and Nira Liberman.
