Method
How the numbers are worked out
Every number on this site is a count of upgrades by stage, so this page is mostly about how a stage is decided. Short for now: the rules below are the ones in force on 16 October 2026; they grow as the list does, and every change to them is dated on the story so far.
What gets onto the tree
An upgrade is one specific technology that changes a human being on purpose: a device, a drug, a procedure, or a practice such as leaning on an always-on AI assistant. To be written down it needs three things: a plain name, a test that says what would count as a person having it (written so that two readers would agree), and a source that would settle that test, meaning a named public record such as a journal, a regulator or a news organisation. Something that cannot be tested that way does not get in.
The five stages
- Idea only. Proposed or worked on, but not yet shown to work in any living animal.
- Shown in animals. Shown to work in a living animal, in a peer-reviewed report.
- First human. At least one person has had it, with a public record of that. Approval is not required.
- In clinical use. A regulator somewhere has approved it, or it is in routine use in a named clinical setting.
- In wide use. Available to the general public in at least one country and taken up by many people.
An upgrade sits on the highest rung a public record puts it on. Each rung reached gets a date and a link to the record that put it there, and the upgrade's page shows the ladder with those dates. Where an earlier rung was reached but the date is not known, the ladder says so rather than guessing.
Three rules that surprise people
- A stage never moves down. If a device is later withdrawn from sale, the entry is marked withdrawn, but the rung it reached stays, because the ladder records what has happened. The count on the home page is a count of things that have happened.
- "First human" does not need permission. A thing done against the rules of the field, or the law, still counts as having been done to a person. The 2018 births of gene-edited children are on the tree at that rung for exactly this reason.
- There are no odds. The sister project, The Belt Equation, gives every event a probability. This one does not, by a ruling of 16 October 2026: a stage, a date and a record say what has happened, and this project does not guess about what will.
The headline count
The number on the home page is the count of upgrades at first human or above, out of all the upgrades on the tree. It is worked out from the record every time the site is built, never typed in. The figure beside it shades each branch by the furthest stage reached under it.
Who does what
John Fredrickson rules on what goes on the tree and on every stage. Claude, an AI assistant, drafts entries, proposes stages and checks records, and built this site. An entry written by Claude from memory carries a list of the claims not yet checked against a source, shown on the entry's page under "Still to check", and the entry is not treated as settled until that list is empty.
What is not here yet
A regular reading of the news against every upgrade, so that a stage change is caught within days; the second number, how much information can pass between a brain and a computer each second, plotted over time on the link to machines page; and the real list of upgrades, of which the four entries on the tree today are examples.