The seat wind marks each player's seat: the dealer is East, the player to the dealer's right is South, opposite is West, and to the dealer's left is North (3.4.6); The prevalent wind names the round — the first round is East, then South, West and North (3.4.5)
Why people argue about this
People often assume that the prevalent wind always starts with East, forgetting that it actually changes with each new round, starting from East in the first round and then rotating clockwise through South, West, and North. This oversight frequently leads to disputes about which player should be designated as having the prevailing wind for a given round.
