Markus Fierz: His character and his worldview

Markus Fierz (1912 - 2006) was Wolfgang Pauli's assistant, friend, prolific correspondent, and eventual successor. In this lecture I briefly review his biography, including my own interactions with him, before turning to some of his thoughts on physics, psychology, and quantum mechanics. His views overlapped and complemented many of Pauli's. My purpose is not so much to celebrate Fierz's contributions to physics as to propose him as a sober, well informed and astute mediator who can help to throw light on the insights of the strange, demonic, and often obscure genius who was Pauli.