The power switch on the back of the Macintosh SE was a small plastic rocker, about the size of a thumbnail, positioned on the left side of the rear panel. It clicked with a satisfying finality. On. Off. The machine did not sleep. It did not hibernate. It did not dim its screen and hover in some ambiguous low-power limbo waiting to be noticed. When you switched it off, it was off. When you switched it on, the startup chime played (a single, clean chord that sounded like a small friendly announcement), and a few seconds later you were looking at a nine-inch screen filled with everything the computer intended to be.
I came to the Macintosh SE late, as a child who encountered one in a library in the early nineties, but I have spent probably more hours than is healthy thinking about what it represented. Not as nostalgia, though there is certainly nostalgia in it, but as a design argument that the industry has spent forty years walking away from and that I believe we need to walk back toward. Especially those of us whose brains were not built for the world we accidentally built.
The Macintosh SE of 1987 ran one application at a time. Not because it had to, exactly. The machine shipped with one megabyte of RAM, and MultiFinder, Apple’s first real attempt at cooperative multitasking, had just arrived that same year as an optional add-on. Most users left it turned off. The single-application model was a choice, and it was a choice rooted in a philosophy that Jef Raskin had sketched years earlier when he first imagined the Mac project. Raskin was long gone from Apple by the time the SE shipped, but his foundational conviction survived three years of product iterations and two leadership changes intact: the Mac was supposed to be honest about what it was doing. It was supposed to do one thing at a time, and to be transparent about what that thing was. The menu bar told you which application owned the screen. The screen filled completely with that application. There was no taskbar full of other things hovering at the edge of your peripheral vision, asking to be clicked.
For an ADHD-i brain, this was not a limitation. It was a boundary.
I did not understand my own neurology for most of my working life. What I understood was that I was better at work when I could not see other work. I was better in environments that had imposed a kind of structural honesty about what the task was, because the executive dysfunction that comes with ADHD-i is not primarily about the ability to work. It is about the ability to choose the work, to start the work, to resist the ambient pull of the seventeen other things that are also technically the work. When a machine could only show me one application, that choice was made for me. The disk was in the drive. The application was on the screen. That was what we were doing today.
There was also something deeply important happening in the physical ritual of it. You inserted a 3.5-inch floppy disk and you waited through the grinding, searching sound of the drive reading it. That sound was a threshold. The mechanical resistance of the disk sliding into the slot, the audible effort of the machine understanding what you had given it, the moment when the icon appeared on the desktop: these were transitions, and transitions matter enormously to brains that struggle to manufacture them internally. The ritual of loading was doing the work of executive function. It was the external scaffolding for a context switch that my brain needed but could not reliably provide on its own.
Modern computing has eliminated transitions almost entirely. The laptop opens mid-session, Chrome reloads its last forty-seven tabs, Slack resurfaces every conversation you were in when you last closed the lid. The machine has no sense of before and after. It does not acknowledge that you left and came back. It simply resumes, mid-sentence, mid-thought, as though no time has passed, as though you have no need for the cognitive equivalent of clearing your throat before you speak.
This is framed, always, as convenience. And it is convenient, in the way that a fire hose is a convenient source of water if you are already on fire and do not need to aim.
The tab culture that contemporary knowledge work has produced is a sensory environment that is explicitly hostile to the kind of sustained thinking that product strategy requires. Strategy is not fast. Strategy is not reactive. Strategy is the work of sitting with a problem long enough that you begin to see its shape, long enough that the easy wrong answers exhaust themselves and the harder right ones start to emerge. That kind of thinking cannot happen in a cognitive environment organized around the shortest possible interval between stimuli. It cannot happen when the pull of the unchecked notification is always present, always offering the small neurological reward of resolution in place of the large neurological cost of sustained uncertainty.
The ADHD brain is particularly susceptible to this, and the irony is that ADHD brains are disproportionately represented in the startup culture that has built and celebrated these tools. We built the infinite scroll. We built the notification system that will not stop. We built the always-on communication layer. And many of us built it while quietly struggling with exactly the kind of focus fragmentation it was going to create for everyone else.
What the Mac 128K knew, accidentally and structurally, was that a tool that forces you to choose is a tool that respects the cost of choosing. Every toggle you add to a system, every parallel process you run in the background, every tab you allow to persist is a claim on cognitive space. That machine made no such claims. It held one thing and held it completely. When you were done with it, you ejected the disk. The machine returned to its sparse, honest desktop. The slate was clean.
I am not arguing that we return to single-threaded computing. I am arguing that we could learn something from the philosophy underneath it when we design the environments in which we expect people to produce their best work. A meeting culture that allows twelve calendar items in a day is not multitasking. It is a context-switching tax so large that it consumes the entire workday in the overhead of switching. An organizational norm that treats the always-open laptop as a sign of engagement is not measuring work. It is measuring the performance of availability, which is not the same thing and never was.
The Macintosh had a physical switch because the people who made it understood that a clear state boundary was a kindness. On and off. Present and away. Working and resting. Those of us whose brains require external structure to manage internal transitions have always known this. The machine knew it too, for one brief, underappreciated moment, before the industry decided that what people really wanted was everything, always, all at once.
They were wrong. But the power switch clicked so nicely that I still remember it.
