Skip to main content

Verified by Psychology Today


Your 'Spontaneous' Laughter Really Isn’t

A dozen variables play a part in every laugh, no matter how rapidly it arises.

Key points

  • Our laughter can at times erupt so quickly, it often seems as if it were an unconscious or reflexive behavior.
  • Most of the factors influencing our laughter have been established days, months, and even years in advance.
  • These may include our knowledge base, personality type, and the relationships we have with those nearby.

Prior posts in this series have explored some of the many factors influencing the perception of vulnerability, the amusement it sometimes fosters, and the desire to express this feeling through laughter. Even though laughter is a conscious behavior, we also must acknowledge that it can arise with little apparent forethought on our part. Indeed, in many instances, our most intense laughter practically explodes from within, almost catching us by surprise. Whatever the trigger mechanism, it appears to operate far too quickly to allow for any substantive cognitive or emotional calculation. So, how does the Mutual Vulnerability Theory deal with this apparent inconsistency?

The following analogy may help to illustrate how spontaneity and rapidity doesn’t necessarily mean simple and automatic.

From something to nothing

Automobiles come in a variety of shapes, sizes, drivetrains, and capabilities, but what they all have in common are their tires. Tires provide the traction needed to propel the vehicle from a standstill, keep it from veering sideways off the intended path, and bring it to a halt when required. As is the case with many mechanical components, they work quite wonderfully. Right up until they don’t.

In addition to the threat of punctures and blowouts, it’s the nature of “tire-ness” that each is... vulnerable, shall we say… to losing traction. Most of us who have been drivers for any length of time can recall an instance when we’ve lost control of our car or truck due to the loss of traction. We made a turn at too fast a speed, slid to the edge of an icy road, or pressed just a bit too hard on the brake pedal during an emergency stop. The tires seemed to spontaneously lose traction, allowing the wheels to either slip, spin, or lock up.

Gerd Altmann/Pexels
Gerd Altmann/Pexels

As serious as this can be, we rarely give the physics behind it much thought. We simply had traction, and then we did not. A little too much speed, snow, or braking force, and the tires “broke loose” from the road. For most of us, that’s all there is to it. But if you were to ask me, a non-engineer, to explain this phenomenon, I would want you to sit down and get comfortable. Even I know it can get rather complicated.

My first items of interest would probably be the tires themselves. I’d want to know their width at the point of contact with the road, the tread depth and design, the side-wall thickness, and the composition of the rubber. I’d look at their age and wear characteristics, as well as the air pressure in each tire at the time of the incident.

I’d continue by looking at the factors influencing the vehicle’s handling characteristics—the load (vehicle and driver, passengers, and cargo), the type of suspension being used at each wheel, and the relative weight distribution.

Then I would obviously want to assess the road surface at the point of failure, including its constituents (concrete, asphalt, brick, gravel, etc.), surface texture, grade (sloping up, down, or to the side), and any foreign materials on the road’s surface—things like sand, clay, snow, ice, oil, or even standing water.

Finally, I’d ask the driver about the initial speed and direction of travel, and if there were any sudden changes in the moment just prior to the skid.

All these factors and more help determine if and when a tire will lose traction. Yet when it does happen, it feels like an on/off switch being thrown. One second you have some, and the next you don’t.

From nothing to something

This is, in reverse, the kind of process that leads to our bouts of laughter, a nonverbal signal that reminds others that we all share some degree of vulnerability. At one moment there’s silence, then… bang, there it is. In actuality, there are numerous variables combining to create, within a given moment and context, a feeling of amusement that puts us over the edge, triggering laughter in all its glory.

Jonathon Burton/Pexels
Jonathon Burton/Pexels

Like tire width, rubber compound, or tread design, some variables are internal and relatively fixed throughout one’s life—our core personality type, parental influences, and cultural background, for instance. Some things change gradually over time, like the wearing down of a tire’s tread—our knowledge base, general health, and political or religious views, for example. Other inputs are like a sudden downpour of rain upon the road—our immediate emotional state and the people with whom we’re interacting, which can vary from hour to hour, and sometimes from second to second.

Together they can result in the equivalent of a little tire squeal, perhaps a coy smile or momentary giggle, or they may put us on black ice, spinning wildly out of control in a fit of fall-on-the-floor, side-splitting, tear-inducing laughter.

We can never be fully conscious of all the factors that come into play, but they will invariably influence whether, and to what degree, we react to potentially amusing stimuli. Laughter often appears to be the result of a near-reflex-like process. As with so many things in life, appearances are deceiving.

This post was drawn, in part, from Chapter Six of Why We Laugh: A New Understanding.

© John Charles Simon.


Simon, J. C. (2008). Why We Laugh: A New Understanding. Starbrook Publishing.

More from John Charles Simon
More from Psychology Today