Welcome to The Nonlinear Library, where we use Text-to-Speech software to convert the best writing from the Rationalist and EA communities into audio. This is: Consider The Hand Axe, published by ymeskhout on April 8, 2023 on LessWrong.

A long time ago, some primitive apes got addicted to rocks.

The earliest stone tools were crude bastards, made by smashing large river pebbles together and calling it a day.

José-Manuel Benito Álvarez

Stone choppers like the one above took the prehistoric neighborhood by storm almost 3 million years ago. However dull the tools themselves may have been, this was the cutting-edge technology for literally more than a million years, a timescale I have no capacity of comprehending. Not until around 1.7 million years ago (again, no idea what this means) that someone got the bright idea of chipping away both sides of a rock. You can see what the (tedious) process looks like.

The end result is the unassuming tear-drop shaped hand axe, by far the longest used tool in human history. There are no accessories here with the hand axe, its name comes from the fact that you use it by holding it directly with your hands:

José-Manuel Benito Álvarez

On top of being tedious and painful to make, you can imagine that it’s not terribly comfortable to hold while using. Hand axes also have to be somewhat bulky because of the necessity of combining the sharp useful end with the blunt holding end. But what if — stay with me for a second — instead of holding the thing directly with our pathetic squishy hands, we held something that “handled” the tool for us? It took humans about another million years to discover hafting, with the earliest examples from around 500,000 years ago but the technique didn’t really find its stride until the microlith era of stone tools around 35,000 years ago.

Then humans found metal.

"Technological advance is an inherently iterative process. One does not simply take sand from the beach and produce a Dataprobe. We use crude tools to fashion better tools, and then our better tools to fashion more precise tools, and so on. Each minor refinement is a step in the process, and all of the steps must be taken."

– Chairman Sheng-ji Yang, "Looking God in the Eye"

The historian Bret Devereaux has an excellent and highly-recommended series on the history of iron. The popular depiction of iron being a rare commodity (typified within medieval and fantasy genre) obscures some of the reality. As a material, iron is extremely abundant — the fourth most common element in the Earth’s crust, making up 5% of its mass. The hurdle with iron wasn’t finding it but rather getting it out of the ground and into a useable form. It required a lot of dead trees and broken shins. One of the illustrations Devereaux cited is from 1556, and shows how workers wore shin protection as they crushed the ore into useable chunks:

Think about how many mangled limbs had to accumulate before medieval OSHA cared enough about this hazard. After the ore is dug out of the ground, the next hurdle was figuring out how to reach the high temperatures needed for processing. Because of how finicky iron is about absorbing too much carbon, the only feasible avenue was charcoal, which is made from wood, which is cut from many many trees. As Devereaux notes:

To put that in some perspective, a Roman legion (roughly 5,000 men) in the Late Republic might have carried into battle around 44,000kg (c. 48.5 tons) of iron – not counting pots, fittings, picks, shovels and other tools we know they used. That iron equipment in turn might represent the mining of around 541,200kg (c. 600 tons) of ore, smelted with 642,400kg (c. 710 tons) of charcoal, made from 4,620,000kg (c. 5,100 tons) of wood. Cutting the wood and making the charcoal alone, from our figures above, might represent something like (I am assuming our charcoal-burners are working in teams) 80,000 man-days of labor. For one legion.

To understate it, much has changed since. A stainless steel spoon t...