For example, in the US in the 1960s the civil rights movement was the focus. But when the movement's demands achieved a certain level of acceptance, fewer people paid such close attention to the problem; a consensus had been achieved. Human history advances in just such a "two steps forward, one step back" way.
就以美國六十年代黑人爭取民權運動為例，當社會達到一定認同程度，就不會有這麼多人關注這樣的議題，因為已經成為人與人之間的共識，而人類歷史就是這樣「前進兩步，後退一步」向前邁進。