When I tell the truth, it is not for the sake of convincing those who do not know it, but for the sake of defending those that do.

Saying a true thing out loud does more than one job. Most of the effort goes into persuading the people who disagree, and that effort usually fails. The quieter effect is on the person nearby who already saw it and thought they were alone in seeing it. Your voice tells them they are not imagining things.

Before you speak up, stop measuring success by whether the room changes its mind. Ask instead who in that room will be steadier for hearing it said. It is easier to speak on days when winning the argument is plainly not available.