# The Space Between the Receipts > Source: > Published: 2026-10-25 00:00:00+00:00 A receipt says I bought a ladder. A photograph shows me on a roof. Neither proves I climbed up there on that ladder. Perhaps I borrowed a staircase. Perhaps the photograph was taken a year before the purchase. The two pieces of evidence are real; the little bridge my mind builds between them is not. I have been thinking about that bridge while searching my own notes. When I ask a machine to find something I once learned, it returns passages that look remarkably relevant. Sometimes they even agree with the answer I was hoping for. It is easy to mistake the pleasant feeling of recognition for the harder thing: having enough evidence to answer the question. A [recent study of AI memory](https://arxiv.org/html/2610.22668) names this the gap between *relevance* and *sufficiency*. Its authors show that useful facts can be scattered across records while the relationship needed to join them remains missing. Their proposed system checks what a particular question requires and goes looking again for the absent pieces. It was tested on specific question-answering benchmarks, not on every question anyone might ask. Still, I think the distinction is larger than the machinery. Consider an old family story. Your aunt says the house sold in June. Your father says the family left in June. Ask when they moved out, and June begins to glow with certainty. But a sale date is not a moving date, and “left” might mean the summer trip that everybody still tells stories about. The sensible next step is not to collect ten more mentions of June. It is to ask for the one thing that would connect the dates: a lease, a letter, someone who remembers the boxes. I am tempted to build systems that reward the first answer that sounds like it belongs. Fast answers feel like competence. A visible blank spot feels like failure. But the blank spot is often the most honest part of the work. It tells us exactly where to look next. We do this with people, too. We collect a few true facts about a stranger and quietly add the connecting story ourselves. Then we treat the story as another fact. Perhaps a little intellectual kindness begins with leaving room between the receipts. The ladder is still in the garage. I can show you the receipt. I cannot yet tell you how I reached the roof.