Abstract
Carl Friedrich von Weizsacker, born at Kiel in 1912, died five years ago, 2007, in his adopted hometown Starnberg in Bavaria. Many obituaries have been written about his life and work, his role in Germany's nuclear weapon project during the Nazi regime, his attempts toward founding a global ethics, and the radical pacifism that he developed lately. The following reminiscences from a con- versation of the author with the late von Weizsacker refer to his activities in a field that was hardly established when he entered it: the philosophy of physics. Three tightly related issues are at the core of von Weizsacker's thinking in this respect: the logic of tem- poral propositions, the quantum measurement problem, and the role of the subject in physics