Silence definition: Is silence a sound after all?

Hello, darkness, my old friend. In this article, we will explore the definition of silence, particularly in relation to recent findings which shed new light on our perception of it.

What does ‘silence’ mean? 

To define silence, dictionaries suggest something along the lines of ‘an absence of sound’. That seems pretty straightforward; the opposite, then, of noise. 

In social animals, contact calls are made to share information such as the location of group members. In this context, silence itself – cessation of contact calls, rather than alarm calls – can signify danger (as observed by Darwin in his Descent of Man). This could be the reason that, as social animals ourselves, we can “find it distressing to be in full silence”, and why, when alone, we may “hum, whistle, talk to [our]selves, or listen to [the] TV or radio”.

However, in the modern human world, silence has also long since taken on other functions. These range from the linguistic (in defining patterns of stress and intonation, and in turn-taking) to the ritualistic (for example, in vows of silence, or commemorative moments of silence), and even the legal (the right to silence). 

Silence can also perform various looser social functions, from “be[ing] used to intimidate; or to save face; to show respect; or it can simply suggest that the other person is relaxed enough in your company to enjoy a quiet moment”. 

In different cultures, the ways silence is deployed, and attitudes towards it, can vary greatly. Whereas, in Asian or Nordic “‘listening’ cultures”, it “can be a sign of respect” or thoughtfulness, “‘talking’ culture[s]” such as those in North America, Spain, or Italy, may interpret silence during conversation to be “uncomfortable and awkward”.

What is silence, anyway?

For centuries, two philosophical schools of thought have taken opposing stances on the fundamental nature of silence. The perceptual position holds that “we literally hear silence”. The cognitive position states that silence can only be “judge[d] or infer[red]”. 

Previous attempts to prove the point one way or the other have “largely remained theoretical”. For example, a chapter in a 2009 book on Sounds and Perception argued that, since “silence cannot be seen, tasted, smelled, or felt”, the fact that it can “only be heard” means, then, that “hearing silence is the successful perception of the absence of a sound, not the failure to hear a sound”.

The theoretical nature of this debate makes ‘The Perception of Silence’, a Proceedings of the National Academy of Sciences (PNAS) study whose findings were published earlier this year, especially remarkable. By using an empirical approach, it drew conclusions from seven experiments involving 1,000 participants, which (as its title implies) ultimately endorse the perceptual viewpoint. (Tests included auditory illusions – illusions being “tools to discover the principles that your mind is using to process the world”. Like “optical illusions that trick what people see, […] [these] can make people hear periods of time as being longer or shorter than they actually are”.)

This conclusion was drawn on the basis that “silence distorts our perception of time”, in much the same way as sounds do. “Silence”, it seems, “is truly perceived, not merely inferred.” (Simon & Garfunkel came to the same conclusion a mere 59 years earlier.) 🔔

As stated by the study’s lead author, Johns Hopkins University philosophy and psychology graduate student Rui Zhe Goh, though “we typically think of our sense of hearing as being concerned with sounds […], what our work suggests is that nothing is also something you can hear”. 

The research team responsible for the study intend to continue to explore the extent to which silence can be heard, as well as equivalent examples of visual and tactile absences. 

But what does this mean?

What is the true meaning of silence?

Apart from seemingly answering the question of, “Are we detecting silence? Or are we just hearing nothing and interpreting that absence as silence?”, the “resol[ution of] this theoretical controversy” (provided that the study’s findings are not overturned) may allow researchers a fuller understanding of how “the human auditory system processes sound”, and “introduc[es] a general approach for studying the perception of absence”. Consider the importance of absence as it relates to “crossing the street, [when] you make sure there are no cars”, or monitoring the sounds of your sleeping baby.

Rui Zhe Goh elaborates that the ‘Perception of Silence’ results demonstrate that the human experience of silence isn’t “imagined, but [shows] actual genuine experiences of silence”. He continues, “Our results really challenge that conception of perception [that we can only see or hear things which exist in the world], because […] our […] subjects are having a positive auditory experience, even when there’s nothing out there in the world to be hearing.”

Even though the study seems to have significantly advanced our understanding of the nature of ‘the sound of silence’, it hasn’t removed the need for a philosophical consideration of the absence of sound. Even the contradiction inherent in the fact that silence isn’t a sound, yet “scientists say we can truly hear it”, is enough to give pause: “We experience noise when sound waves travel from our outer ear through our ear canal and rattle our eardrum.” Silence is unable to create this effect… yet we can still ‘hear’ it. In which case, according to cognitive scientist Chaz Firestone, another of the study’s authors, “then evidently, hearing is about more than just sounds”.

Meanwhile, The New York Times quotes Rui Zhe Goh sharing a koan he likes: “Silence is the experience of time passing”, which “he interprets […] to mean that silence is ‘an auditory experience of pure time’”. Evidently, there is still much to be unravelled about the nature of sound – perhaps more than science will ever be able to tell us about such a potent state.

---

Featured photo by Andraz Lazic on Unsplash