In 2021 a well-crafted cover letter still meant something. It was evidence of care, of effort, of a candidate who could compose their own thoughts. In 2026 the same letter arrives, just as well-crafted, from a candidate whose recommenders drafted one paragraph and delegated the rest, whose portfolio is polished and may or may not be their own work. The letter, the degree, the portfolio, the recommendations: all still arrive. What no longer arrives with them is a signal.
This is not a story about AI. It is a story about verification.
The economy of expensive signals
Every institution in the modern economy runs on signals that used to be expensive to produce. A cover letter cost time. A published paper meant a peer review committee stayed up late. A licensed contractor cleared a board’s exam, in a room, with a proctor watching. A five-star review came from a real person who had actually eaten dinner. A GitHub commit meant somebody had thought carefully enough about a problem to type a solution and put their name on it. Each signal cost something, and that cost was the reason to trust it. When a signal becomes cheap to produce, it stops being a signal. The word for a signal that costs nothing is noise.
The list of signals that have collapsed in the last three years is longer than most people notice. Undergraduate essays. Coding samples, book reviews, product reviews. Testimonials on real estate agents. The friendly outreach message that used to signal a real person had read your work. AI did not destroy any of these directly. What the AI destroyed was the cost of producing a plausible version of them, which is the same thing.
The vacuum is not new
The printing press did this once already. Before 1450, holding a book meant truth and status: production was so laborious that the friction itself filtered out the frivolous. After 1550 the same book was one of ten thousand, and the signal of “I have written this down” collapsed. What followed was not un-inventing the press but a century of forgeries and pamphlet wars, and then verification. The learned societies that emerged to vouch for a new discipline called science ran an old model: admission by the testimony of members who knew your work, standing that could not be printed, only conferred. When the first journals wanted their papers believed, they had practitioners read them and put the society’s name behind them. We call that peer review now. It is witnesses signing.
Verification is what filled the vacuum the press created. It took a while. The Royal Society was chartered two centuries after Gutenberg. Many of the institutions we now think of as timeless were built or remade in that gap, one by one, as answers to a specific question: given that anyone can now produce a plausible book, how do we know who to listen to?
We are in that vacuum again. Not because writing became cheap, that happened generations ago. It’s because everything that used to be evidence of care, effort, or authorship can now be produced without any of them, in seconds, by a machine or a person with a machine’s help. The paper, the code, the letter, the design, the review: all still arrive. None still proves that anyone did the work.
What survives
There is one signal this doesn’t touch, and it is the oldest one: someone who was there, staking their name on what they saw.
A colleague who shipped a system with you and can tell you which design calls were yours, and which one they argued against. A collaborator who worked on the album and can name what you contributed on which track. A student who was in your lab for three years and can describe the specific patience you showed them the week they wanted to quit. This kind of testimony can be lied about, but it cannot be automated, because the thing being spent is not words. It is a reputation that took years to build, staked by a person who has something to lose if the sign-off proves false. Their reputation lives with the mark they leave on yours. That is the friction the printing press could not eliminate, and the friction the current generation of tools cannot eliminate either.
This is not a new kind of trust. It is the oldest kind. Guilds ran on it. Bar associations run on it now. Every real reference offered voluntarily, on a candidate someone actually worked with, is one instance of it. Every editor who has ever put their name on a piece by a young writer, every senior engineer who has vouched for a junior in the promotion committee, every board member who has signed off on a treasurer’s audit, is participating in an institution built on witnessed testimony.
What is new is that we have never systematically recorded it. The closest the digital era has come is the LinkedIn endorsement: a one-click vouch, offered in seconds, often for a skill the endorser never saw used. It failed exactly the way this essay would predict; a sign-off that costs nothing is noise. The best we have managed on paper, for the last three hundred years, is the letter of recommendation, which is impossible to check and hostage to the writer’s willingness to spend an hour on someone else’s career.
Recording it
The problem is recording, not trust. Trust between people who work together has always existed. We have even recorded it before, but always in someone else’s vault: the credit bureau queried behind your back, the platform that sold ads against your answers and videos (and kept the rights to themselves).
The vacuum the printing press created took a century to fill. This one will not take a century, because we already have the infrastructure to record durable sign-offs in real time, at costs that used to be impossible. The signature of a colleague, the vouch of a mentor, the certification of a professional body, the peer reviews in a journal. Each of these can now be recorded in a form that outlasts any single company and belongs to the person named in it. What is missing is not will but design: a record worth keeping for the first person who keeps one, before anyone else is checking, and protected from the aggregators that would flatten it back into another cheap signal.
The unverified signals are gone. What’s left is the signature of someone who was there.
Ken Leiserson builds tools for trust between people who work together. He can be reached at app.extol.work/profile/ken or on X @kenserson.