Here are some semi-random thoughts on play that I have been accumulating.
Repetition with variation
Imagine you were observing an animal whose behavior you didn’t know anything about. How would you know if it was playing?
One clue would be repetition of the same basic movement pattern with random variation. If you saw the animal repeating the same movement without any variety, you might think it was working, stressed or anxious. Think of an animal pacing back and forth in a cage. Now imagine the animal going through the same basic movements, but with some random changes - instead of just walking back and forth, it sometimes turns, jumps or changes speed. That would look more like play.
On the opposite end of the spectrum, imagine the animal doing movements that were completely random. That wouldn’t look like play either, it would probably look like the animal was insane. Healthy behavior has at least some sense of continuity or purpose. So play is some kind of pleasurable combination between repetition and variation (or maybe work and insanity).
It is interesting to note that this formula is used in many forms of serious training. Strength coaches often use an array of exercises that are “the same but different.” The program is composed of a few basics (squats, lunges, pushes and pulls) with varying constraints (equipment, resistance, set/rep schemes, grips, foot positions, etc.) Non-linear pedagogy, a school of coaching that relies on Dynamic System Theory, emphasizes the importance of using games that create “repetition without repetition.”
I think this is one of the reasons why balls inspire so much playful behavior in the animal kingdom. Even if you are always trying to do basically the same thing with the ball - catch it, or throw it, or keep it away from someone else - the ball always moves a bit unpredictably, interjecting random variation into a repetitive activity.
Play and natural selection
Evolution by natural selection requires just a couple of conditions to get going. First, reproduction of some pattern with random variation, and then selection among the different patterns according to some criteria. Repeat this process over time, and whatever pattern you are reproducing (organisms, internet memes, clickbait articles) will start to evolve in the direction of being better able to satisfy the selection criteria.
Karl Popper pointed out that the scientific process of knowledge acquisition is in some ways similar. We make hypotheses or theories that try to explain some phenomenon, and then put that hypothesis to the test by experiment. Again there are two basic elements - conjecture and criticism. Conjectures that pass the test of criticism get accepted as provisional truths and reproduced in the writings of others, until they are criticized again and eventually fail a test, which invites new modified conjectures and new tests. The result is that our theories evolve to get better at explaining what we see.
You can think of motor learning in this way as well. Each movement can be used as a kind of hypothesis about its ability to accomplish some desired function. The sensory feedback tests the hypothesis: did we accomplish our goal or not? Over time, we come up with movements that are better able to satisfy our functional goals.
For example, when babies reach for something, they find out whether they get what they are reaching for. And then what it tastes like. A lot of their motor learning happens by mistake. They are trying to reach a toy over their head, and all of a sudden they roll. Hmm that’s interesting ...
Because progress like this is often unplanned, it's a good idea to make some random movements from time to time to see what happens. A playful attitude is a natural incentive to be creative, include unplanned events, and otherwise force us to continue experimenting with new kinds of movements, even when the problem has already been solved to a good degree of satisfaction. Better solutions might be out there, and a very conservative, workmanlike approach can miss these if the intention is to always succeed or minimize error.
Play is not infantile
The word play is associated with behaving in a way that is childlike, silly, or infantile. That’s a bit unfortunate, because it suggests that a playful approach would not be a good way to solve adult problems. False!
What if we substitute a slightly different word for play like “tinker” or “experiment”?
Imagine how you might go about fixing a problem with a complicated machine like a computer or a DVD player. You don’t know exactly what is causing the problem or how to fix it, but you might succeed by just kind of randomly messing around with ways to get the computer working again - fiddling with the controls, turning it on and off, playing with different settings, etc.
This is what a kid would do to solve a computer issue, and it works better than what many seniors would do, which is to consult a manual, have someone else do it, or give up.
Or consider a pro golfer whose swing feels off. They might go to the range and start playing around with different grips, different swing paths, or attentional cues. This creative tinkering process doesn’t have a strict plan, it is just a way of exploring possibilities and waiting for something to fall into place. It might work better than asking a swing coach for advice.
I think this tinkering attitude often explains how we actually succeed at improving movement and pain. We don’t always know exactly what is wrong or how to fix it, but by playing around with different options, sometimes we arrive at a destination without really knowing how we got there.