There is some discussion over how to interpret that, but if
we take it literally it is surely true. On the third hand
it is very incomplete, and it is a bit of a red herring,
because it focuses attention on the wrong variables.
I say the goal should be to learn efficient and effective methods
for solving important and interesting problems. If an important
problem can be solved easily, so much the better.
To be sure, sometimes you have to spend a penny before you can
earn a guinea, but there is no simple relationship. Results are
generally not proportional to effort. It's not even a monotone
function. Indeed, it's not even a function at all! There are
several reasons for that, starting with the fact that often there
are multiple ways of achieving the same result, associated with
wildly different costs. Also the results you get today are not
a function of how hard you work today, because they greatly
depend on how hard -- and how wisely -- you worked during previous
days, months, and years.
I say the motto should be: In this class we don't solve hard
problems. We solve interesting and important problems. Some
of the problems /would have been hard/ if you didn't know the
tricks ... so let me show you the tricks.
====
I have this vivid picture in my mind of a bunch of muscular
villagers who have chopped down an enormous tree. They are
using it as a battering ram, trying to force open the front
door of the dragon's castle. Grunt. Smash. Grunt. Smash....
Meanwhile, the wizard gets on his bicycle and zooms around to
the back door of the castle. He picks the lock. He runs inside,
rescues the hostages, and carries off a few sacks of emeralds
from the dragon's hoard.
The wizard's approach is more effective and more efficient ...
but that does not mean that the wizard is lazy. Ask yourself,
where did that bicycle come from? Where did those lock-picks
come from? The answer is that the wizard invested years of
effort constructing those things, and acquiring the skill to
use them. It was well worth it, but it was by no means easy.
In general, you don't maximize the return on investment by
maximizing the investment ... or by minimizing it. The idea
is to invest wisely.
Learning is an investment. Fussing over more time-on-task or
more hard work is asking the wrong question.