Taking an oath

The American rule on witnesses says what an oath is for, and says it in a way no engineer could implement. Before testifying, a witness must swear or affirm, in a form designed to impress that duty on the witness's conscience. The instrument is built to act on something inside a person, and the law keeps a second lever for the case where it fails, since a false oath is a crime with a name and a sentence. English law has the same shape and lets the person choose the words, because what matters is that this particular person is bound. A model can produce a sworn statement in any register asked of it. Nothing in it can be impressed, and nobody can be prosecuted for what it swore.