Lowering your voice when someone raises theirs is a power move that looks calm and feels terrifying.

Matching someone’s volume hands them control of the exchange, because now the conversation runs at whatever temperature they set. Going quieter breaks that. It costs a great deal internally, since every instinct is pushing the other way, and it looks from outside like the easiest thing in the room.

When the volume climbs, slow down and drop a level rather than meeting it. Say less, and leave gaps. If the other person cannot come down to meet you, end the conversation for now instead of continuing it at their pitch.