Donal Rumsfeld and statistics

This morning I attended a conference of Dr. Lars Jermiin and, in order to illustrate the statistics behind evolutionary models, he introduced to the public a quotation of the former United States Secretary of Defense. I think this deserves a place in our popular cultural imaginary:

As we know,
There are known knowns.
There are things we know we know.
We also know
There are known unknowns.
That is to say
We know there are some things
We do not know.
But there are also unknown unknowns,
The ones we don't know
We don't know.

D.H. Rumsfeld