Pin (chess) Pin (chess) In chess, a pin is a situation brought on by an attacking piece in which a defending piece cannot move without exposing a more valuable defending piece on its other side to capture by the attacking piece. Moving the attacking piece to bring on the pin is called pinning; the defending piece so restricted is described as pinned. Only pieces that can move an indefinite number of squares in a horizontal, vertical, or diagonal line (i.e. bishops, rooks, and queens) can pin. Kings, knights, and pawns cannot pin. Any piece can be pinned except the king, since the
When a white horse is not a horse explains "'A white horse is not a horse', because the name diverges from the shape." Two "Zhuangzi" chapters (17 and 33) mock Gongsun Long, and another (2) combines his "zhi" 指 "attribute" and "ma" 馬 "horse" notions in the same context. To use an attribute to show that attributes are not attributes is not as good as using a nonattribute to show that attributes are not attributes. To use a horse to show that a horse is not a horse is not as good as using a non-horse to show that a horse is not a horse, Heaven and earth