Kill an Assumption
in 3 Minutes
I am not a violent person. I’m the guy who feels bad for clothes in his closet that don’t get worn. I worry about rodents in your pantry that are just trying to stay warm in winter. I have named several spiders in my house and some of them have middle names.
But I will murder an assumption.
Because assumptions are not the harmless little background beliefs we pretend they are. They are not kind spindly creatures with no poison for little Johnny — they are black widows and you have to protect your world from them. They sit quietly in the corner, blending in with the architecture of your thinking, and they will kill your project, your strategy, your relationship, your entire creative life — without thinking twice. I once spent a million dollars on a feature film built on top of assumptions I never bothered to check. We won festivals. Fans loved it. Warner Bros. called. And it still died, because we made a movie that everyone thought was for someone else — no intentional genre in a time when multi-genre wasn’t a genre. That’s what happens when you let assumptions drive. They don’t use blinkers.
side note: this is the pocket knife version of our full Killing Assumptions exercise. The longer version takes 45 minutes and leaves a much bigger mess. This one takes three minutes. You only need one assumption. And you need to be honest enough to actually say it out loud.
Here’s how it works. You’re going to name the assumption. Then you’re going to run it through three rapid-fire reframes — each one designed to hit the thing from a different angle. Think of it like defusing a bomb made of your own beliefs. Except the bomb is ticking. Because it is. Right now. Whether you run this exercise or not.
You might as well look at the wires.
You already know what it is. It’s the thing you haven’t questioned because it feels like a fact. It’s the “well, obviously” that runs underneath your strategy, your org design, your Tuesday afternoon. It’s the belief you’d bet the house on. Which is exactly why it’s dangerous. Because you probably already have.
Write down one assumption you are currently operating under — in business, life, or both.
Say it plainly. “I assume that...” — No hedging. No softening. Put the thing on paper like you’re putting it on trial. Because you are.
The fastest way to stress-test a belief is to flip it. Not to be contrarian. Not to be clever. But because the opposite of your assumption often contains an intelligence that the original can’t see. Echo learned this one the hard way — she assumed her friends couldn’t come with her on the journey. She assumed it was “how might I” when the truth was “how might we.” One pronoun. Entire world changed.
What if the exact opposite of your assumption were true?
Flip it completely. If you assumed “our customers want cheaper options,” try: “our customers want to pay more for something worth paying for.” What world does that open up? What would you do differently tomorrow?
This one is meaner than it looks. Some assumptions don’t need to be true or false. They just need to be irrelevant. They’re the things that feel load-bearing but are actually just decorative. You’ve been solving for them out of habit. The habit of solving for the wrong problem is one of the most seductive habits a smart person can have. I should know. I’ve been that person more times than a rodent has been cold.
What if this assumption simply didn’t matter?
Remove it entirely. If the assumption vanished overnight and nobody noticed, what does that tell you? What decision have you been avoiding that has nothing to do with this belief? What would you be free to build?
Now we get weird. And I say that with love. This is the reframe that nobody expects because it goes straight through the front door instead of sneaking in the back. It’s improv logic: yes, and. What if the thing you assumed is not just true but is actually the entire point? What if the constraint is the feature? What if the limitation is the story? Creation and reaction have the exact same letters. It’s simply a matter of seeing them in a different order.
What if this assumption was the whole point?
Lean into it entirely. If you assumed “we’re too small to compete,” try: “we’re small, and that IS our competitive advantage.” What strategy emerges when the thing you’ve been fighting becomes the thing you build on?
Stop. Read back what you wrote. All four boxes. The assumption and its three alternate realities. Somewhere in there, something shifted. Maybe it was subtle — a small crack in a thing you thought was solid. Maybe it was seismic and you’re sitting there a little unsteady right now. Good. That wobble is the feeling of a worldview updating in real time. That’s the feeling of the paper bag tearing.
What shifted? And what are you going to do about it?
Which reframe surprised you? Which one made you uncomfortable? That discomfort is data. It’s telling you where the assumption had roots. Name the shift. Then name one thing — one tiny, concrete, doable thing — you will do differently because of what you just found.
For Facilitators
This exercise scales beautifully. Run it solo, in pairs, or with an entire room. For teams: have everyone write their assumption silently. Then pair up and run each other’s assumptions through the three reframes — it’s far more brutal (and useful) when someone else does the reframing. The person who owns the assumption just listens and writes.
For larger workshops: collect the assumptions anonymously. Read them aloud. Let the room reframe them together. You will be amazed at what surfaces when people realize their “personal” assumptions are shared by half the room. That’s when a culture starts to shift — when the hidden becomes communal.
Rules from the ideation hackathon apply: stay in yes/and at all times, silence is okay (it breeds courage), and the only bad idea is to kill ideas. You’re killing assumptions here, not ideas. There is a profound and important difference.
What You Just Did
You held a belief up to the light from three different angles and watched how the shadow changed. That’s it. That’s the entire technology. The reason most strategies fail, most brands sound the same, and most people stay stuck isn’t a lack of intelligence or resources. It’s a failure to interrogate the things we already believe. We build beautiful solutions on top of unexamined assumptions. Then we wonder why the beautiful thing doesn’t work.
Our assumptions lead to our actions and create our biases. These little buggers make certain that we look for research to support what we already suspect. It’s a sure way to never empathize, stay in an either/or, and also never make any real friends in life. Sorry for that last one. Just thought you should know.
The full version of this exercise goes deeper — it takes you from assumption killing into worldbuilding, where the cleared ground becomes the foundation for something new. But this three-minute version? It’s the match. It lights the fire. And sometimes all you need is the fire to see what was hiding in the dark.
Run it again tomorrow on a different assumption. Run it on the same one in a month and see if it sticks. Run it on every “well, obviously” you catch yourself saying. The practice is the point. The killing never stops because the assumptions never stop arriving. They breed like those warm rodents I was telling you about.
tip: know empathy, know friends. no empathy, no friends.
This exercise is designed to be printed, shared, and used in workshops. Take it. It’s a gift. Use it to set fires responsibly.
Kill an Assumption is one of several narrative design exercises we develop and teach at storylab.
We give them away before they’re finished. See what else is in the lab →