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 am mostly a Java programmer but I really enjoy writing Lisp code. It’s not really weird in my opinion, but the programmer must format the code nicely for it to be readable. If you do that it looks like any other language to me , except it has very little syntax so feels a bit more pure. Similar to Forth which has essentially no syntax, just white spaces between tokens. In Lisp it’s just lists all the way. Just so you know, in lisp you can do procedural programming, ie line after line of instructions… it’s just not the common way to do things, people write much more functional code than in most languages.