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How many people did it take to build the Great Pyramid?

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Re: How many people did it take to build the Great Pyramid?

#41

Post by toomanybeersies »

est31 wrote: post #9
burlesona wrote: post #2

This is very cool to see. The main takeaways for me were: 1. It's easy to underestimate what is possible when you limit thinking to a short timescale. I think of the cathedrals, temples, mosques, etc. that have been built all over the world, where the people who started the work knew they wouldn't live to see it finished, but that didn't dissuade them. Or conversely, it's easy to overestimate the difficulty of someth…

There is a star trek episode where they encounter a civilization which has built a benevolent AI a long time ago and has since lost capabilities to do much more than give commands to the AI. Our society has managed to write down some things like math for example so our knowledge as species won't be lost if mathematicians suddenly died. But it's harder to find permanent storage for the more skills based human activiti…

I don't know if NASA themselves could stick Saturn engines onto new rockets, but I reckon the Air Force probably could. Air force technicians are pretty good at fabricating and fitting parts from what I've seen.

Skills like hand fabrication and fitting aren't something that you can store. You can record videos or interview skilled tradesmen as much as you want, but the real skill is something that is learned through experience, it's muscle memory and intuition, not theoretical knowledge.

Re: How many people did it take to build the Great Pyramid?

#42

Post by necubi »

burlesona wrote: post #2

This is very cool to see. The main takeaways for me were: 1. It's easy to underestimate what is possible when you limit thinking to a short timescale. I think of the cathedrals, temples, mosques, etc. that have been built all over the world, where the people who started the work knew they wouldn't live to see it finished, but that didn't dissuade them. Or conversely, it's easy to overestimate the difficulty of someth…

This is echoed in a fascinating r/AskHistorians comment I read recently [0]. The question was about how the Romans forgot how to make concrete in the late empire. I highly recommend reading the whole thing, but the gist is: as the empire became poorer, demand for huge building projects (typically funded by the state) declined. Eventually, after a couple hundreds years, the tradition was lost entirely.

Losing knowledge like this was much easier in earlier eras when fewer people were literate. Trade knowledge would be passed down via apprenticeships and rarely written down. So it only takes one generation of the apprenticeship system breaking down for the knowledge to be lost entirely.

(Also, for anybody unfamiliar with r/AskHistorians, it's one of the best corners of the internet! Professional historians provide in-depth answers to random questions about history.)

[0] https://old.reddit.com/r/AskHistorians/comments/gntlr8/how_d...

Re: How many people did it take to build the Great Pyramid?

#43

Post by ssivark »

necubi wrote: post #42
burlesona wrote: post #2

This is very cool to see. The main takeaways for me were: 1. It's easy to underestimate what is possible when you limit thinking to a short timescale. I think of the cathedrals, temples, mosques, etc. that have been built all over the world, where the people who started the work knew they wouldn't live to see it finished, but that didn't dissuade them. Or conversely, it's easy to overestimate the difficulty of someth…

This is echoed in a fascinating r/AskHistorians comment I read recently [0]. The question was about how the Romans forgot how to make concrete in the late empire. I highly recommend reading the whole thing, but the gist is: as the empire became poorer, demand for huge building projects (typically funded by the state) declined. Eventually, after a couple hundreds years, the tradition was lost entirely. Losing knowledg…

> Losing knowledge like this was much easier in earlier eras when fewer people were literate.

The thing is, there are many aspects to doing things which can’t be written down. So even today, the one generation concept is meaningful. There is a deep “use it or lose it” spirit in biological systems. We might think of ourselves in primarily literate/rational terms, but that’s far from the truth.

Re: How many people did it take to build the Great Pyramid?

#44

Post by peeters »

umvi wrote: post #40
Areading314 wrote: post #38

This analysis ignores friction in the calculations for energy/manpower needed to construct the pyramid. I wouldn't put much stock into these results

Yeah they just calculate the potential energy as if workers can move limestone blocks with perfect efficiency in frictionless conditions. It wouldn't surprise me if it took 2-4x its potential energy (or more) to move any given block into place.

How many people does it take to push a two-ton rock up a hill and then back to where it started? Apparently zero.

Re: How many people did it take to build the Great Pyramid?

#45

Post by pvg »

burlesona wrote: post #2

This is very cool to see. The main takeaways for me were: 1. It's easy to underestimate what is possible when you limit thinking to a short timescale. I think of the cathedrals, temples, mosques, etc. that have been built all over the world, where the people who started the work knew they wouldn't live to see it finished, but that didn't dissuade them. Or conversely, it's easy to overestimate the difficulty of someth…

I think of the cathedrals, temples, mosques, etc. that have been built all over the world, where the people who started the work knew they wouldn't live to see it finished, but that didn't dissuade them.

I wonder whether that's not really more the exception rather than the rule - some famous cathedrals just took a long time. But lots of huge projects were completed in one or two decades or less - the pyramids, the Coliseum, the Taj Mahal, the Pantheon, Hagia Sophia, etc.

Re: How many people did it take to build the Great Pyramid?

#46

Post by LanceH »

peeters wrote: post #44
umvi wrote: post #40

Earlier quoted context omitted.

Yeah they just calculate the potential energy as if workers can move limestone blocks with perfect efficiency in frictionless conditions. It wouldn't surprise me if it took 2-4x its potential energy (or more) to move any given block into place.

How many people does it take to push a two-ton rock up a hill and then back to where it started? Apparently zero.

The economist says that if you pay the rock enough it will move itself.

Re: How many people did it take to build the Great Pyramid?

#47

Post by spyckie2 »

I love stuff like this.

I've always wanted to find a community that collaborates to determine as much as possible the rough range of the total cost, either in man hours, dollar amount or other metrics, of things we see, know, and interact with every day. I think it is even more interesting if you try to estimate the cost of the research the thing depends on (which greatly scales up the complexity but also the fun of the exercise).

For instance, what is the manhour cost of google.com historically? You can approach it in so many different ways - revenue analysis, # of employees in google search team over the years, or just guess at how much you would need to build google.com yourself today.

Subreddit suggestions for different styles of this kind of activity:

===

/r/resetPrice

Imagine that the infrastructure of the world has reset to the stone ages but we still retain all modern knowledge. What's the price, in man hours, of rebuilding things that we use every day and take for granted?

What is the reset price of google.com?

What is the reset price of Seattle?

What is the reset price of a mechanical pencil?

===

/r/CTMH

Cost in Total Man Hours

What's the CTMH of the NY philharmonic orchestra playing for one evening?

What's the CTMH of developing the entire iPhone phone line series, from original to current model?

Also similar - /r/ETEB - Estimated total effort to build

Re: How many people did it take to build the Great Pyramid?

#49

Post by jiggawatts »

utopcell wrote: post #48

Ahem.. I'm just going to drop this link here on how the pyramids were _really_ built: https://youtu.be/TJcp13hAO3U

That's rather... imaginative.

Certainly, water played a role: much of the stone was shipped from quarries some distance away.

It's also imaginable that they used canals to bring the blocks further inland, closer to the pyramid construction site.

However, the near-vertical water tower and lock system would be a challenge to build today, let alone with the technology of the era. The pyramids were built before the widespread use of the wheel, and with soft copper tools, not bronze. They predate the invention of nails, as in the type used to join wood. For example, the planks of Khufu's ship were bound together with knotted ropes and its sails were moved without the aid of block and tackle, as this would have required wheels and axles! It's a sight to behold...

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