because of calculation, logical sequencing and abstracting reasoning.
because games are experiments in which we learn. Because each body is trying to upset the homeostasis of the other body
because a chessboard has an equator which is called the frontier line, on the 64 squares there are ranks or the lines of latitude, and files are the lines of longitude
because rooks are the banks, the bishops the religious class, the knights the military, the pawns are the everyday people, the king and queen the ruling class.