Ask HN: If Donald Knuth woke up 10,000 years ago, how would he build a computer? | Hacker News Reader

Ask HN: If Donald Knuth woke up 10,000 years ago, how would he build a computer?

Assume he knows what he knows now, but is a strapping young man.

He wouldn't. He would finish TAOCP. Frankly the math is more important than any chunk of hardware.

Even if he just got really bored and wanted hardware, I don't think he would have the knowledge to do it. It is one thing to know how to use all the tools, it is another thing altogether to know how to engineer high quality tools with nothing but sticks, stones, and no help.

Well, he still uses a computer to run his TeX program to write TAOCP, so I wouldn't exclude that he would build a computer. Also, it's not that complicated to build an electromechanical computer.

As I see it, the hardest part is making the magnets to generate electricity from a water mill. Then you only need some copper and to make a lot of wire out of it, and you can make electro magnets for the gates. (It seems to me to be even easier to build than Babbage's mechanical computers).

This is the man who, when he wanted good looking typesetting for the second volume of TAOCP, spent over a decade making TeX to do that with.

Of course he would stop and build a computer first. And universities where people would read his books, banking and mail institutions to send people checks through after they report bugs, and so on. One needs to have some preconditions in place first, obviously.

I think that even a mechanical computer like Babbage's would be pretty far beyond what you could accomplish with the technology available 10K years ago - to make precision gears you'd need a machine shop, and to build that you'd need to be able to build the machines and tools, and to make those you'd need to be able to refine metals, etc. 10000 years ago was 5000 years before the Bronze Age and 3000 years before the Iron Age. It would be hard for one person to reconstruct all that technological infrastructure single-handedly (and as far as I know, Knuth knows a lot about CS but not a whole lot about metalworking). And to build any kind of electronics (e.g., vacuum tubes or relays) you'd have to be able to manufacture glass, wire, etc. Forget semiconductors...

(I assume that by "computer" you mean a device that can store a program in memory and execute it.)

This reminds me of an old quote from Mr. Spock on Star Trek:

"I am endeavoring, ma'am, to construct a mnemonic memory circuit using stone knives and bearskins." [1]

[1] http://www.imdb.com/title/tt0708455/quotes

With a little creativity. computers can be made out quite primitive items. Of course, one might need to define what constitutes a computer.

The Tinkertoy Computer

A. K. Dewdney's article, "Computer Recreations: An ancient rope-and-pulley computer is unearthed in the jungle of Apraphul

Domino computer

http://www.blikstein.com/paulo/projects/project_water.html

Lehmer sieves

How to Build a Working Digital Computer (1967)by Edward Alcosser, James P. Phillips, and Allen M. Wolk

He would bang stones together. Then, on finding the different tones they make he would discover the inherent math in music. He would then utilize this to make a basic program to make people dance. From this he would find out about looping (repeating sections of music).

Then he would invent a way for others to program (musical notation) and start to write it on cave walls. But, unhappy with the quality of the charcoal used for writing he would devote years to developing a new type of ink capable of pretty printing.

Finally he would retreat to a distant cave to work on The Art of People Programming.

I don't think he would build a computer. 10k years ago was before writing. I imagine if anyone were transported that far back they'd want to focus on the stuff that has a huge impact (hygiene, food, basic medicine, potable water, writing, architecture, etc.) for the people at that time period.

There's a lot of common things we all know that we take for granted that would make a world of difference for people so long ago.

Most readily available material is sticks. Make em into gears powered by water flow in a river. Your very own prehistoric calculator. After ciliization starts mining and improving it's ability to shape raw materials your computers can advance with it.

Version 1:

Hey mum!, what's this animal?

Oh, my fungus!, a human thing!, aren't they extinct? throw your scholar computer to it, and crawl as fast as you can, little blob!.

Alternative version:

1)-Chose the colour of your computer

2)-Press a button.

"Thanks Mr. Knuth, your new computer will be 3D-printed in computer modern and delivered in 20 minutes".

https://en.wikipedia.org/wiki/Quipu

He'd build the the Abacus 10000BC using advanced wooden disk and stick technology.

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