I often write about learning faster and learning more efficiently as if they were the same. And in many cases, they are. If it would normally take you 100 hours to learn a subject, and by cutting waste you can get that down to 50 hours, you’ve learned faster and more efficiently at the same time.

我经常将“更快地学习”和“更高效地学习”视为同一回事。在很多情况下，它们确实差不多。如果通常需要 100 小时来学习一个主题，通过减少不必要的步骤可以将时间缩减到 50 小时，那么这意味着你同时实现了更快和更高效的学习。

But sometimes learning faster and learning efficiently don’t mean the same thing.

有时候，学习得更快和学习得更有效率并不是一回事。

Consider two approaches to learning calculus. One, you take a week, and spend twelve hours a day studying. The second, you take four months, but you only spend an hour each day. You’ve invested roughly the same number of hours, so assuming you have the same knowledge at the end, the two approaches were equally efficient (In fact, the slower one is probably more efficient due to the spacing effect, but I’ll get to that later), but the one-week approach is much “faster” than the second in terms of the total time elapsed to learn calculus successfully.

有两种学习微积分的方法可以考虑。第一种方法是，你花一周时间，每天学习十二个小时。第二种方法是，你花四个月的时间，但每天只学习一个小时。虽然你投入的总时间大致相同，假设最后掌握的知识也一样，那么这两种方法效率相当。（实际上，由于间隔效应，慢一点的方法可能更有效率，但我稍后会解释这个。）不过，从学习成功所需的总时间来看，一周的方法明显“更快”。