Never in my fondest dreams did I expect in January 1957 to be invited, twenty-eight years later, to reminisce about decisive experiments on symmetry violation in a great national laboratory directed by Leon M. Lederman. Such reminiscences not only are unnecessary (some of the key protagonists having already published their recollections in Maglich's nowdefunct journal) but also can be misleading. Nobody has total recall, and personal souvenirs can get warped by things heard but not experienced. Just recall Einstein's contradictory answers to the question whether he was or was not aware of the Michelson-Morley experiment in 1905.

Theoretical prologue

My friend Laurie Brown has asked me to include in my talk some remarks about the history of the theoretical developments in the field of weak interactions, as several of the main contributors to this field are present here but have chosen not to talk. I shall oblige Laurie Brown in some sense, but still avoid giving a chronological presentation devoid of personal reminiscences. Such presentations are available in standard textbooks.

Let me not praise famous men: It might be embarrassing (or insufficient) to them and to me. Let me instead mention a few early contributions that, for one reason or another, have rarely been cited in past reviews.

Before the famous Lee–Yang paper on parity nonconservation, theorists generally stated that there existed five different four-fermion couplings.