Light thinks it travels faster than anything but it is wrong. No matter how fast light travels, it finds the darkness has always got there first, and is waiting for it.
南怀瑾:世间法不空,与般若有挂碍,等于眼中有沙,认生死轮回为实有;出世间法不空,与般若亦有挂碍,等于肉中有刺,认化城为宝所;故有凡夫生死、二乘涅盘的颠倒梦想。