Week 9: Building With Others

Crossing 5's lecture — why a thing built with a stranger isn't your half plus theirs, and why this is the first report-back that isn't only yours

5 October 2026

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Half and half, like every lecture: George Curious on why building with someone is a different transaction from everything you’ve done so far, Moana Liza — Crossing 5’s tutor — on how you actually do it with whatever is lying around, and what you owe the room afterwards.

George’s half — why build with someone

Four Crossings in, you have met four kinds of stranger: someone you said something to, someone you traded with, someone who walked up to a stall your team had built, and someone who could have said no to you and maybe did. In every one of them the other person was on the far side of the exchange. Find a Partner in the Hall puts them on your side of it, which is a harder thing to arrange and a much harder thing to fake.

The failure mode has a shape, and George names it early: you agree on a thing, you each go and do a piece, you staple the pieces together and call it a build. Sawyer and DeZutter’s study of improvised theatre is the framework for why that isn’t the same object — they analyse a creative process in which no single participant’s contribution determines the result, and list what a group needs for that to happen. An outcome nobody has scripted. Each move depending on the one just before it. Anyone’s later move able to change what an earlier one meant. Split the work in two and you have removed all three on purpose.

So the price of this Crossing isn’t nerve, or an object, or a no. It’s sole authorship: you give up the right to decide how the thing turns out, to somebody whose name you learned that morning. And because two people made it, this is the first Crossing where the account of it isn’t only yours either — What We Made is a report with someone else’s decisions in it, and George closes their half on the test that follows from that. Not “was it worth doing” this time, but: would your partner recognise the thing you just described?

Moana’s half — how you actually do it

Moana teaches Crossing 5 the way she teaches everything, which is to look at the bench before looking for an idea. Cardboard, wire, a broken umbrella someone left in the Maker Space, a common-room Lego shelf, a phone that records: what’s in reach decides what two strangers can plausibly make in an afternoon, and deciding it the other way round is how people end up negotiating a concept until the hallway empties.

Which is where the marshmallow comes in. Wujec has run the same eighteen minutes — twenty sticks of spaghetti, a yard of tape, one marshmallow on top — with tens of thousands of people, and kindergarteners reliably build taller than business students, because the kids start putting sticks into the marshmallow immediately and the students spend the time planning and then have none left to fix what the plan got wrong. Build in the first five minutes. You will be wrong faster, which is the point.

The other half of the craft is what you do with what your partner says, and improv has had the vocabulary for it longer than we have: everything is an offer, accepting is saying yes to the reality they’ve put in front of you, and blocking is rejecting it. Johnstone’s line is that good improvisers look telepathic because they accept all offers made — take the offer and you get a build; block it and you get your own idea with a witness. Moana closes on what leaves the hallway with you: the fifth and final clip, shot under the rules on Policies if your partner is in it, and a report next week that covers a decision that wasn’t yours.

What you should leave knowing

Teaching team