{"id":179,"date":"2026-02-24T00:59:40","date_gmt":"2026-02-24T00:59:40","guid":{"rendered":"https:\/\/projects.etc.cmu.edu\/ghaist\/?p=179"},"modified":"2026-04-10T21:31:09","modified_gmt":"2026-04-10T21:31:09","slug":"week-6-the-full-picture-clicks","status":"publish","type":"post","link":"https:\/\/projects.etc.cmu.edu\/ghaist\/week-6-the-full-picture-clicks\/","title":{"rendered":"Week 6 – The Full Picture Clicks"},"content":{"rendered":"\n

“What if the experiment is just the appetizer?”<\/strong><\/p>\n\n\n\n

This was the week everything came together. Not in a “we finished the game” kind of way, but more like the moment when you’ve been staring at scattered puzzle pieces for weeks and suddenly you see how they all connect. We now have a complete experience design from start to finish, and more importantly, we know why<\/em> each piece is there.<\/p>\n\n\n\n

Let’s walk you through it.<\/p>\n\n\n\n

Four Phases of a Ghost Story<\/h3>\n\n\n\n

The experience we’re building has four distinct phases, and each one has a specific job to do.<\/p>\n\n\n\n

Phase 1<\/strong> is all about the hook, and it starts before anyone even sits down. The installation is already alive: picture frames on the back display are visibly distorted, something is clearly wrong, and a soft voice loops from the diary on the table. Priestley, reaching through time. It’s not loud or aggressive. Just enough to make a passing teenager pause and think, “What is that? Who’s talking?”<\/em> In a museum setting, you have maybe five seconds to earn someone’s curiosity. This is how we spend them.<\/p>\n\n\n\n

Phase 2<\/strong> is the meeting. The player opens the diary, and Priestley’s ghost addresses them directly. He is challenging the players, the chosen one, to solve the riddles and uncover the secret.<\/p>\n\n\n\n

Phase 3<\/strong> is the carbonation experiment, and this is where players discover what Priestley actually accomplished. He guides them through his most famous achievement: the invention of carbonated water. On the touchscreen diary, players select materials and make choices. They grind chalk, pick their liquid, and use physical props on the table to complete the process. The big screen mirrors everything in real time, so friends and bystanders can watch along.<\/p>\n\n\n\n

Here’s what makes it work: wrong answers are fun<\/em>, not punishing. Pick chili water? Priestley “tastes” it and absolutely loses it. Use milk? He’s baffled but oddly impressed. Every choice produces an entertaining reaction, which keeps players experimenting instead of worrying about getting it “right.” When the experiment succeeds, the corresponding picture frame on the display bursts back to life. Memory restored.<\/p>\n\n\n\n

Phase 4<\/strong> is where the real magic happens. We call it the Yes-or-No Mystery<\/strong>.<\/p>\n\n\n\n

After the experiment, Priestley drops something unexpected. Something like: <\/p>\n\n\n\n

“In my time, I set chalk in motion with oil of vitriol, releasing what I called fixed air. Now, your first question\uff1aI often borrowed ingredients from my wife Mary\u2019s kitchen for my experiments. One common liquid there could also help produce sparkling water. Can you guess which one<\/em>?”<\/p>\n\n\n\n

Priestley gives a mysterious, incomplete statement about his life, and the player’s job is to figure out the full story by asking yes-or-no questions. It’s like a detective game powered by conversation. In groups, players naturally start debating what to ask next, throwing out theories, reacting to Priestley’s answers together. And because so much dialogue is flowing, Priestley’s personality comes through organically: his humor, his stubbornness, his passion for science, his (sometimes spicy) opinions on other scientists.<\/p>\n\n\n\n

The experiment lets players know what Priestley did<\/em>. The mystery lets them discover who he was<\/em>.<\/p>\n\n\n\n

This is also where the LLM technology truly earns its place. The mystery requires handling completely unpredictable player questions, which is exactly what a language model excels at. Combined with real-time voice synthesis, Priestley can respond to anything, not just pre-scripted lines. The conversation feels genuine and alive in a way that a branching dialogue tree never could.<\/p>\n\n\n\n

What the Installation Actually Looks Like<\/h3>\n\n\n\n

Picture an 8-foot space that feels like stepping into Priestley’s study. In the front, a table holds physical props: flasks, bladders, containers. At the center sits the diary, a touchscreen built into an open-book form factor that serves as the player’s main interface. Behind it, a screen displays illustrated picture frames representing key moments from Priestley’s life, faded at first, vivid and detailed once restored.<\/p>\n\n\n\n

The Winding Road to “Simple”<\/h3>\n\n\n\n

Of course, the design didn’t arrive fully formed. We went through a couple of earlier approaches that taught us a lot about what doesn’t<\/em> work for our audience.<\/p>\n\n\n\n

One early idea was handwriting-based interaction. Players would write messages in Priestley’s diary by hand, and he’d respond. It sounded magical on paper (pun intended), but in practice the handwriting recognition was unreliable, younger students struggled with it, and the writing speed made the whole experience feel sluggish. More importantly, we realized that even with perfect tech, open-ended conversation alone didn’t give players enough structure. Without a goal, people would ask a few questions and then not know what to do next.<\/p>\n\n\n\n

We also tried a more faithful recreation of Priestley’s experiment, where players followed precise scientific steps: selecting the correct acid, choosing the right calcium source, adjusting water amounts. It was scientifically rigorous, but it played more like a chemistry quiz than an adventure. Teenagers don’t get excited about optimizing chemical ratios. And we were putting all the focus on the science when our real goal was to make people care about Priestley as a person<\/em>.<\/p>\n\n\n\n

Those two experiences led us directly to the current design. Simplify the experiment into a quick, entertaining introduction that showcases Priestley’s achievements. Then use the Yes-or-No Mystery as the core mechanic where players genuinely get to know him through conversation. The experiment is the hook. The mystery is the heart.<\/p>\n\n\n\n

What’s Next<\/h3>\n\n\n\n

We’re heads-down building the first complete loop: entering the scene, meeting Priestley, running the experiment, and playing through the first Yes-or-No Mystery. The goal is to get this into the hands of real teenagers as soon as possible and see if it holds up. We’re also layering in sound design (ambient audio, experiment effects, UI feedback) and refining Priestley’s character voice for consistency.<\/p>\n\n\n\n

Once the first level is solid, we’ll expand to additional experiments and mysteries. Priestley’s discovery of oxygen is the most likely next chapter.<\/p>\n\n\n\n

The ghost is finding his voice. And he has a lot to say.<\/p>\n\n\n\n

\n\n\n\n

<\/p>\n\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

“What if the experiment is just the appetizer?” This was the week everything came together. Not in a “we finished the game” kind of way, but more like the moment when you’ve been staring at scattered puzzle pieces for weeks and suddenly you see how they all connect. We now have a complete experience design […]<\/p>\n","protected":false},"author":2,"featured_media":204,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-179","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/projects.etc.cmu.edu\/ghaist\/wp-json\/wp\/v2\/posts\/179","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/projects.etc.cmu.edu\/ghaist\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/projects.etc.cmu.edu\/ghaist\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/projects.etc.cmu.edu\/ghaist\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/projects.etc.cmu.edu\/ghaist\/wp-json\/wp\/v2\/comments?post=179"}],"version-history":[{"count":2,"href":"https:\/\/projects.etc.cmu.edu\/ghaist\/wp-json\/wp\/v2\/posts\/179\/revisions"}],"predecessor-version":[{"id":182,"href":"https:\/\/projects.etc.cmu.edu\/ghaist\/wp-json\/wp\/v2\/posts\/179\/revisions\/182"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/projects.etc.cmu.edu\/ghaist\/wp-json\/wp\/v2\/media\/204"}],"wp:attachment":[{"href":"https:\/\/projects.etc.cmu.edu\/ghaist\/wp-json\/wp\/v2\/media?parent=179"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/projects.etc.cmu.edu\/ghaist\/wp-json\/wp\/v2\/categories?post=179"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/projects.etc.cmu.edu\/ghaist\/wp-json\/wp\/v2\/tags?post=179"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}