The issue with play structures is that they train you to play only within affordances. When the space that you play in is designed by someone else, you are pushed towards playing only in the ways that they envisioned. A play structure affords a small set of actions, and as a player, you only get to pick which one you prefer. There’s no invention in that, no spontaneity, no creativity.

Let’s think about how this applies to adults. If you show an adult a library of video games, they can pick one and click the “play” button. But show an adult a meadow with trees to climb and grass to roll around in, and they will write it off as unplayable (unless they are with friends, and typically playing a standard game with standard rules).

~ Alex Hollow from, https://www.lesswrong.com/posts/oy8xbZ8s8v8PDdCZ3/playing-without-affordances

Understanding this (if you don’t already) will bend your mind, in a good way. People who understand what Art du Déplacement is, talk about developing a new kind of “vision”. It’s hard to describe what this new vision is—perhaps I can say, it’s like seeing motion… or, where normal vision can induce a mood, this new kind of vision can suggest a movement. I went to a show recently, and sitting in the balcony before the house lights went down, my wife and I had a completely serious discussion of “how do you get down from here [without using the obvious stairs]?” At other times we stop to play on things. I regularly walk along curbs and swing from things I find overhead.

It’s not that things lack affordances. No, there are affordances everywhere… in, on, around, under, throughout every object natural and man-made. If you lose—as it seems everyone does as they‘re forced grow into adulthood—your vision for playing, only then does it appear that affordances are missing.

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