People in experiments have missed a stranger swapping places mid-conversation. Don’t be so sure you saw it all.

The strangest part of attention is that it does not report its own gaps. You feel like you are taking in a whole scene, when in fact you are holding two or three things and inventing continuity for the rest, and the invention is seamless enough that a person can change and you will not notice. There is no internal alarm for missing something.

So say what you actually noticed rather than what you saw. In an argument about events, the honest sentence is that you remember this part and were not watching the rest. That care makes you a better witness, and harder to argue with.