Mean-field particle methods

Mean-field particle methods are like playing tag in a big field with a lot of people. To start, each person in the field has a card with the same number written on it. When someone is "it" and they tag someone, the person they tag has to change their card to the number that theirs was originally. Everyone runs around changing numbers with each other until all of the cards have the same number on them. This is like the mean field particle method because it's trying to make all of the particles equal.