“We live under the shadow of a gigantic question mark. Who are we? Where do we come from? Whither are we bound? Slowly, but with persistent courage, we have been pushing this question mark further and further towards that distant line, beyond the horizon, where we hope to find our answer.”
—Hendrik Willem Van Loon The History of Mankind
这是美国著名的历史学家房龙在《人类的历史》的开篇写下了的一席话。从what到how的认知过程也可以理解为主动学习的一种方法。