There is big Hayek scholarship news in the new Caldwell & Klausinger biography of Hayek. The philosophically significant Hayek-Popper correspondence will appear as an additional volume of the Hayek Collected Works. 1/n

I own copies of the philosophical most interesting and important parts of the correspondence, and I can report they they discuss the shared Popper and Hayek theme of the importance of negative rules and negative knowledge -- what we cannot know and what we must not do .. 2/n

.. and the deep relation between these two kinds of understanding and their relation to the brain and our understanding of social phenomena. 3/n

A truly important and difficult domain of philosophical, scientific, and social inquiry jointly explored by Popper and Hayek in their scientific, philosophical, and social theory work. 4/n