When Germany occupied Denmark in 1940, physicist Piet Hein published an innocent-seeming poem:

Losing one glove
is certainly painful,
but nothing compared to the pain
of losing one,
throwing away the other,
and finding the first one again.

The German censors let it go, not understanding its meaning — that while enduring occupation was bad, ceasing to resist would be worse. “It said that what happens to you from outside is less important than how you take it,” he explained later. “The Danes knew what I meant.”

In later years Hein cultivated a talent for such tiny aphoristic poems, which he called “grooks”:

Problems worthy
of attack
prove their worth
by hitting back.

There is
one art,
no more,
no less:
to do
all things
with art-
lessness.

The road to wisdom? — Well, it’s plain
and simple to express:
Err
and err
and err again
but less
and less
and less.

Put up in a place
where it’s easy to see
the cryptic admonishment
T.T.T.
When you feel how depressingly
slowly you climb,
it’s well to remember that
Things Take Time.

In all he wrote more 7,000 grooks, which have become a part of Scandinavian culture. “I cannot really say where my activity as a scientist ends and where my activity as a man of letters begins,” he said. “Whether I am writing a poem or solving some technical problem, I think the same.”