The Freedom of Self-forgetfulness

I recently read a little book by Tim Keller entitled, 'The Freedom of Self-forgetfulness'.  In it he makes the following point

Up until the twentieth century, traditional cultures (and this is true of most cultures in the world) always believed that too high a view of yourself was the root of all evil in the world ... Our belief today - and it is deeply rooted in everything - is that people misbehave for lack of self-esteem and because they have too low a view of themselves ... A truly humble person is not a self-hating person or a self-loving person, but a gospel-humble person ... Not thinking more of myself as in modern cultures, or less of myself as in traditional cultures.  Simply thinking of myself less.