Static or dynamic?

A thought provoking statement against static type systems:

Type systems fundamentally put a box around us to limit the kinds of programs we can express to a class that is known to be "good" in some sense. That means that when we find a new idea or idiom, we might not be able to express it. Even worse, the box creeps into our minds and limits even our thoughts about programs to stay inside the box, so we won't even think of the idea.

http://lambda-the-ultimate.org/node/4389#comment-67944