- A single stacked chart: eight columns – seven eras since the 1880s plus 2025→? – where every layer is a skill that was once the bottleneck and is now baseline.
- Reading rule: the highlighted layer is the currently scarce skill; every layer beneath it got tooled and the value moved one layer up.
- The eighth column shows all seven layers commoditised and a dashed, unclaimed layer on top – Domain Judgment – marked as a hypothesis, not a record.
Each era, yesterday's scarce skill becomes the new baseline. The scarce skill (highlighted, glowing) is always one layer above where the previous era left off.
Show the data – 8 eras, 7 layers
Table 1. Same sequence as the diagram above: which skill was the bottleneck in each era, and how many layers underneath it had already become baseline.
| Era | The scarce skill | Layers below it, already baseline |
|---|---|---|
| 1880s–1940s | Statistical Intuition | 0 |
| 1950s–1970s | Programming & Algorithms | 1 |
| 1980s–1990s | SQL & Databases | 2 |
| 2000–2012 | Distributed Systems | 3 |
| 2012–2020 | ML & Data Science | 4 |
| 2016–2022 | Deep Learning | 5 |
| 2022–Now | Coding (LLMs) | 6 |
| 2025→? | none – all seven are baseline | 7 |
Every column is a moment in time. Every layer beneath the glowing one is a skill that used to be the bottleneck and now isn't – it got tooled, and the value moved up. The 2025 → ? column shows all seven layers as fully commoditised baseline, with a dashed, unclaimed layer on top: Domain Judgment. That layer is marked differently on purpose. It hasn't happened yet, and – unlike every layer beneath it – it might not happen the same way. The other seven columns are a record. The eighth is a question.