Donald Rumsfeld – There are known knowns

2020-06-12

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 – there are things we do not know we don’t know.“
Donald Rumsfeld, 2002-02-12

citation

Marcel Achard – New Ideas