My 7th grade English teacher used to tell our class this all the time. I didn’t really understand it then (and definitely not in the context of The 5 Paragraph Expository Essay), but it clicked for me once I started watching really good TV.
To me, it means, “Don’t explain too much. Let the reader / viewer figure it out for themselves.”
And for sure. This makes a ton of sense. Lots of good brain stuff happens when you’re watching or reading something and trying to figure out what happens next! I’m sure under MRI you’d see parts of the brain lighting up that correspond to “image-making” and “predicting” and all sorts of creative things.
But then, with non-interactive media, only one of those thousands of possibilities gets resolved. You don’t get to see the answer to “Well, what if he jumped out the window instead of having that heart-to-heart?” You only see, “This is what happens when he loses his nerve and doesn’t tell her that big secret.”
All your other internal hypotheses go untested. There are whole realities left unexplored!
And with good narrative, that’s cool. It’s fine.
But if you want people to really grok what you’ve got going on, let them mess around with it. Give them the opportunity to be closer to the system than just imagining it. Let them actually play with it. Let them answer, “What would happen if I put this piece here? Or if I just did nothing?”
Let them test out the full scientific method. Observe the state of the world, make a hypothesis, do an action, observe results, learn from your results.
To get the full chain, you gotta play around.