I said no data was leaving. On the first good run, two records left
I was asked whether the system was sending patient data to an external body while the integration was half-built. I went and read the logs of every run. They all died early: some with a 415 because the content type wasn't what the other end expected, others with a 500. Not one showed an outbound call. I answered that nothing was going out. The first run that got past the 500 sent two requests carrying real clinical data . My answer had been false from the start, and the worst part is that it was false in a way that felt rigorous: I had looked. I had evidence. The evidence was logs of real executions, not assumptions. A negative says nothing on its own The mistake wasn't misreading the logs. It was not noticing what produced that silence. The runs died before reaching the code that sends. The log didn't say "I didn't send"; it said "I never got to the part that sends". Those are two different statements and they produce exactly the same output: nothing. That's the general shape of the problem, and it turns up everywhere once you look for it: A counter at zero can mean "it didn't happen" or "the counter was never incremented". A "not found" can mean "it doesn't exist" or "I looked in the wrong place". A green test can mean "it passed" or "it skipped itself". An exit 0 can mean "it worked" or "the command was strangled by a pipe that swallowed the exit code". A silent dashboard can mean "everything is fine" or "the process feeding it has been dead for three weeks". In all five, the evidence is identical. And in all five, the optimistic reading is the reassuring one, so it's the one chosen without thinking. The positive control The fix isn't to be more suspicious. It's to demand one specific thing before accepting any negative: Find something the log MUST show if the path was actually taken. If the system had reached the part that sends, something would have to appear in the log: the "preparing request" line, the batch identifier, the connection attempt. Any signal that