(Science Week, day 4!)

What would you set up for yourself, if you could spend eternity doing anything you could imagine?

That was supposedly, I was given to understand as a child, what "heaven," or the afterlife, was like. And I personally imagined something like a simple apartment. In it would be a classic Macintosh, and on that would be HyperCard.

I made my first few games on HyperCard in grade school: simple adventures like Dungeon Escape where you examined a hasty drawing of the area, clicked one of several buttons or areas, and moved to another drawing. For more complex games like Paddler, my little sort of Pong clone – or Mansion Escape, where you had a persistent inventory of items – I learned the "HyperTalk" language for the custom programming. All of this occurred in 512-by-384 resolution with pixels that were either on or off. No colour, no grayscale.

I've never taken for granted the utter fortune of being one of the first children ever to have something like HyperCard. It would have seemed like magic to the prior century – something they might have to imagine for their personal afterlives. But, of course, it isn't magic. The electronic circuit, the transistor, the monochrome display, the operating system, the mouse, the application itself, and so on, have all been invented and just so combined. Each puzzle piece was fully understood by its inventors, and can theoretically be understood by anyone.

I chose HyperCard on the Mac for my "afterlife," mainly because I knew I liked using it. I liked the intrinsically rewarding challenges of programming and working within the computer's limitations.

But, for eternity, when I could have anything I could imagine? If I really wanted to make games forever, couldn't I have an environment where I could simply speak, or even think, scenarios, characters, physics, and plots into existence with imagery as vivid and convincing as that of reality – something like a Star Trek holodeck, involving no effort, no challenge, and no limitations?

And so, I carried on growing up having decided I would have two setups in my eternal apartment: one utterly real, and one utterly not real.

Or so I thought, until the last year or so.

Even as that child, I could tell humanity was approaching the "elbow" of a profound technological uptick. Things would get ever more impressive and extraordinary, ever more quickly. Plenty of what's come since then, like iPhones and SSDs and broadband and solar panels, seemed reasonable then. But I don't think I ever expected the present-decade arrival of the ability to simply type or speak a request to a virtual entity to pen a story, draw a picture, make a video, or write a program almost instantly.

The emergent term for this general scheme is "AI," which I think is unfortunately too broad and potentially misleading. And at the time I'm typing this, the churning general hype and controversy around the technology (perhaps owing in part to those characteristics of the term) seem to have upstaged the actual enjoyment of what it does well, and a healthy curiosity about what it really is and how it really works.

Those questions – what it is and how it works – deserve their own posts. In brief: I'm given to understand this kind of program is most efficiently executed on "neural processors," like mini-computers optimized to run them, because the low-level computation is analogous to the neuronal "computation" of a brain. This suggests that studying "AI" rewards the studier with some insight into neuroscience as well. I've also heard it put that the technology is in essence closer to autocorrect than to intelligence, which I can believe. When its flaws surface in light of a lack of ability or a lack of source data, these complex programs can resemble amusingly simple ones.

But the point is made: without unpacking the technology any further than that, it's clear that the unpacking is a meaningful and rich endeavour. Like HyperCard on the Mac, "AI" was invented, is understood by its inventors, and can theoretically be understood by anyone. Its ability to conjure creative output is one component of my childhood imaginings. Is the rest of the fantastical holodeck – a room full of realistic, three-dimensional illusions into which one could wander and begin dictating games like a film director – well on its way to arriving in reality, as well? Even if not: VR headsets yielding essentially the same effect are already impressive in their early adolescence.

By the way: later in my growing-up, attending to my curiosity about the workings of the brain, I no longer see any reason to expect an afterlife of any kind, for any of us. It appears that science and human ingenuity have done something at least as astonishing: they have taken something I had always regarded as specifically magical, worthy of an afterlife-like fantasy, and enabled me to spend part of my actual life understanding how what it really is, and how it really does work.