public boolean equals( Object other ) {
    if ( other == null ) {
      return ( false );
    }
    else if ( other == this ) {
      return ( true );
    }
    else if ( other.getClass() != this.getClass() ) {
      return ( false );
    }

    Move otherMove = (Move) other;
    return ( this.to == otherMove.to() && this.from == otherMove.from() );
  }