I hope you see the difference between building a Geiger tube and buying one.

Building a Geiger tube is probably beyond the reach of most people. That’s a precision piece of equipment.

I'd argue that it is beyond the perceived reach of many people, but it is not beyond the actual reach of many people.

The key ingredients are aspiration and time.

This got me thinking: how far down the current human tech tree could a single person get on their own? It took thousands of years for humans to go from fire to the steam locomotive; could someone do it in a lifetime?

Obviously the ability to skip by basic research and dead ends would cut this down by a ton, but ultimately a lot of the things we’ve created in the past century requires a huge amount of complicated machinery to make, which requires more machines and more labor. Could a person reasonably start from scratch (let’s say skip the mining and just give them coal & metal ores) and make a Geiger tube? Or would it be too difficult?