picture a sixteen year old opening her first bank account. she brings an id. a parent comes along to sign. a clerk looks at both of them and says yes. every step in that room needs a person. a face, a name, a signature, and somebody willing to vouch. now think about the software that is starting to do small jobs for you. a program that books the cheapest train. a program that buys one map lookup, or one minute of computing, from another program. people call these agents. an agent is software that acts for you without asking each time. an agent has no face and no parent. it cannot walk into that room. so today it borrows your card. that works for a train ticket. it works poorly when the job is ten thousand purchases of a tenth of a cent each, made at night, between two programs that have never met. card systems were built around a person who can be called, billed and refunded. the fee on each purchase is larger than the purchase. three words keep coming back to me. private means a rival cannot read every purchase your software makes. neutral means no single company decides which programs may pay. permissionless means a program can start paying without waiting for somebody to approve an account. i think software needs money that asks for a key and never asks for a name. bitcoin works that way. to hold it you need a secret number called a key, and a program can keep a key as easily as you can. lightning is a faster network built on top of bitcoin, and it sends tiny amounts in about a second for a very small fee. the pushback is fair. banks and card companies are building this too, with spending limits and refunds, and for most of what you buy those protections are worth having. a key has no refund desk. if your software gets tricked, that money is gone. what would show me wrong: two years from now, most payments between programs run on cards and bank accounts, including the tiny ones, and the fees did not get in the way. until then i watch the small payments. a tenth of a cent has no room for a clerk in it. bitcoin has never asked who is holding the key, and that old habit fits a customer with no face. if this made you picture software standing at a bank counter, Zap ⚡

picture a barber shop with four chairs. the owner is proud of it. last spring he added a new way to pay, and he taped a small sign by the mirror to say so. he knows how it works. he set it up himself on a slow tuesday. now picture a busy friday when he is out. a customer finishes his haircut at chair three and asks to pay the new way. the barber at chair three has never opened the app. there is a line by the door. he says what any of us would say. "can you use your card today?" the customer taps a card. the sign stays on the mirror. that moment is where i look when people talk about shops taking bitcoin. let me walk through it. bitcoin is digital money that moves without a bank in the middle. for small purchases most shops use lightning, a faster network built on top of bitcoin for everyday payments. to get paid, the shop's app shows an invoice, a one-time request for an exact amount, drawn as a square code the customer scans with a phone. all of it can be learned in ten minutes. someone still has to teach it. a card reader needs no lesson. every barber in that shop has used one a thousand times. the new way lives in one person's head, and that person goes home at night, takes holidays and gets sick. so here is my claim. a shop takes bitcoin as often as the person standing at the till knows how. i would trade the sign on the mirror for ten minutes of practice with every member of staff. the other side has a fair point, and i want to give it room. maybe training changes nothing, because customers are not asking. a barber can know every step and still go a month without one request. if the demand was never there, teaching the staff will not create it. that could be right. what would show me wrong: shops where every worker has been trained and has practiced, and the share of customers paying this way stays as low as before. bitcoin has worked the same way every day since 2009. the money was ready long ago. on a busy friday the question is whether the barber at chair three is ready too. if this made you think about who is standing at the till, Zap ⚡