The lost cause of the Lisp machines

> I'm hearing more and more people outside the tech world talk about the AI bubble, and predicting it's going to pop

I'm juuust about old enough to remember the end of the Lisp Machine bubble (we had one or two at uni in the early 90s, and they were archaic by then). But obviously Lisp machines were the wrong way to go, even if they were a necessary step - obviously, hardware-mediated permanent object storage is the way forwards! POP! Ah, maybe not. Okay but can't you see we need to run all this on a massive transputer plane? POP! Oh. Okay how about this, we actually treat the microcode as the machine language, so the user-facing opcodes are like 256 bits long, and then we translate other instruction sets into that on the fly, like this - the Transmeta Crusoe! It's going to revolutionise everything! POP! Ah, what? Okay well how about...

And we're only up to the early 2000s.

It's bubbles, all the way back. Many of these things were indeed necessary steps - if only so We Learned Not To Do That Again - but ultimately are a footnote in history.

In 30 years' time people will have blog posts about how in the mid-2020s people had this thing where they used huge sheds full of graphics cards to run not-working-properly Boolean algebra to generate page after page after page of pictures of wonky-looking dogs and Santa Clauses, and we'll look at that with the same bemused nostalgia as we do with the line printer Snoopy calendars today.

Also Maxima.

Yes, but they're "Hello world!" hostile, so traditional programming language pedagogy doesn't work well.

Q: How many Prolog programmers does it take to change a lightbulb?

A: Yes.

I'm not so sure it's down to the hardware. With something like 180-bit wide microcode store - a very very horizontal microarchitecture - the hardware sure was specialised, but I think it's fundamentally down to Lisp itself.

I don't know a lot of Lisp. I did some at school as a teenager, on BBC Micros, and it was interesting, but I never did anything really serious with it. I do know about Forth though, so perhaps people with a sense of how both work can correct me here.

Sadly, Forth, much as I love it and have done since I got my hands on a Jupiter Ace when I was about 9 or 10 years old, has not been a success, and probably for the same reasons as Lisp.

It just looks plain weird.

It does. I mean I love how elegant Forth is, you can implement a basic inner interpreter and a few primitives in a couple of hundred lines of assembler and then the rest is just written in Forth in terms of those primitives (okay pages and pages of dw ADDRESS_OF_PRIMITIVE instructions rather Forth proper). I'm told that you can do the same trick with Lisp, and maybe I'll look into that soon.

But the code itself looks weird.

Every language that's currently successful looks like ALGOL.

At uni, I learned Turbo Pascal. That have way to Modula-2 in "real" programming but by then I'd gotten my hands on an account on the Sun boxes and was writing stuff in C. C looked kind of like Pascal once you got round the idea that curly brackets weren't comments any more, so it wasn't a hard transition. I wrote lots of C, masses and masses, and eventually shifted to writing stuff in Python for doing webby stuff and C for DSP. Python... looks kind of like ALGOL, actually, you don't use "begin" and "end", you just indent properly, which you should be doing. Then Go, much later, which looks kind of like Pascal to me, which in turn looks kind of like ALGOL.

And so on.

You write line after line after line of "this thing does this to that", and it works. It's like writing out a recipe, even more so if you declare your ingredients^W variables at the top.

I love Forth, I really want to love Lisp but I don't know enough about it, but everyone uses languages that look like ALGOL.

In the late 1960s Citroën developed a car where the steering and speed were controlled by a single joystick mounted roughly where the steering wheel would be. No throttle, no clutch, no gears, just a joystick with force feedback to increase the amount of force needed to steer as the car sped up. Very comfortable, very natural, even more so when the joystick was mounted in the centre console like in some aircraft. Buuuuut, everyone uses steering wheels and pedals. It was too weird for people.

> I'm hearing more and more people outside the tech world talk about the AI bubble, and predicting it's going to pop

You know what they say about when the taxi driver is giving you strong financial opinions.