How This Or That Writing Prompts Actually Work
This Or That Writing Prompts are exactly what they sound like: you get two options, you pick one, and you write. There is nothing mystical about it. It is a constraint-based exercise, which means the limitation is the whole point. Writers often stare at a blank page for twenty minutes before producing anything. This format removes that paralysis by forcing a decision. You do not need to find the perfect prompt. You just need to pick A or B and go. The structure is simple. A prompt presents two contrasting or related elements and asks you to commit to one. For example: a door that only opens at midnight or a bridge that only forms at dawn. You choose. Then you write a scene, a story, or even just a paragraph. That is it. No essay structure required. No three-act plan. Just pick and produce. The reason this works is because it bypasses the planning phase entirely. Most writers get stuck in worldbuilding and character sketching before they ever draft a sentence. The constraint forces forward motion. You are not writing a novel yet. You are writing three hundred words about a chosen option. That is a manageable scope.
Practical applications
I use this format in workshops all the time. It works well for warm-ups, for when a group needs to generate raw material quickly, or for anyone who wants to test a premise without committing to a full draft. I have seen people produce better first pages in fifteen minutes with This Or That than they do in two hours trying to "find their voice." You can run this solo or in a group. Solo version: grab a list of pairs, pick one, write for twenty minutes with no editing. Group version: pass around cards with two options each, everyone picks one and writes. The social pressure element actually helps. You are less likely to second-guess yourself when ten other people are typing.
A specific problem I ran into
Early on I noticed a pattern where people would pick the same option every time. In a group of twelve, eight people chose the door option and four chose the bridge. This created repetitive stories and killed momentum. The workaround was to add a rule: if you picked that option before, you must take the other one. It feels arbitrary but it forces variety. The bridge writers were the ones who produced the most interesting pieces in every session I ran. They had to dig deeper because the concept was less familiar to them. Most people think the harder option is the better choice. They are wrong. The easier option usually produces better writing because you are not wasting cognitive load on figuring out the rules. If one choice is vague and the other is specific, pick the specific one. "A clock that runs backward" gives you more to work with than "a moment frozen in time." The vaguer the option, the more mental energy you spend interpreting it instead of writing. Another thing beginners miss: the contrast between the two options matters more than the options themselves. Two similar choices (a red door or a blue door) rarely generate compelling stories. Two opposed choices (a door that lets you travel vs. a door that lets you read minds) create tension by default. The friction between A and B is where the interest lives. If both options pull in the same direction, the exercise falls flat.
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When this format fails
This approach does not work for writers who need extensive outlining. If you are someone who cannot draft without a detailed scene-by-scene plan, the constraint will frustrate you. You will waste more time deliberating between A and B than you would saving a blank document. For those people, a structured prompt with a clear scenario works better. There is also a ceiling on how far you can push this. After you write a few dozen short pieces, the novelty wears off. The exercise becomes a mechanical warm-up rather than a genuine creative tool. At that point, you should move to longer form constraints or character-driven exercises instead of continuing with binary prompts.
Where to find them
You can find lists online fairly easily. Search for "this or that writing prompts" and you will hit several curated databases. Some are free, some require a subscription. The free ones are usually sufficient. I recommend starting with a smaller list of thirty to fifty pairs rather than scrolling through hundreds. Too many options reintroduce the paralysis you are trying to avoid. Take this pair: a library where every book writes itself or a garden where every plant grows into a different animal. Both are serviceable. The library option gives you immediate access to narrative structure since books imply stories. The garden option gives you physical transformation scenes. If I were assigning this, I would suggest the library for character-focused writing and the garden for action-focused writing. The pair itself is not the point. The alignment between your choice and your actual goal is what matters. Start with a timer. Twenty minutes. No editing during the write. Pick one side. Write. Stop when the timer ends. Review what you have. You will usually find something usable even if it is rough. That usable fragment is worth more than the perfect idea you never acted on.