The seminar included a very entertaining recollection of how the idea came about, and what were the initial reactions of several of the main characters of the theoretical physics arena in the sixties of last century (including Feynman, who was originally very sceptical but then accepted the idea toward the end of the sixties). The acceptance of the reality of quarks was in general quite slow, and Zweig was more of a believer of the concrete existence of these constituents than was originally Murray Gell-Mann, who had cooked up the same idea working with group theory and liked more to think of quarks as mathematical entities rather than real ones.
(Above, Zweig after the seminar)
I was astonished to hear the story of the 80-pages paper on hadron constituents that Zweig wrote in 1964, and was unable to get published. He was working as a US visitor at CERN back then, and papers had to be undersigned by Leon Van Hove, who was then the head of the theory division (he later became Director General of CERN) before they got submitted to journals. He wanted papers to be published on European journals only, but Zweig wanted to publish on Physical Review. The clash resulted in the paper remaining in the drawers for 16 years... Van Hove even instructed his secretary, madame Fabergé, not to type any of Zweig's articles, to make sure he would have it his own way !
After the seminar I hung around with Zweig and a few of the conference participants, and we continued the discussion and a recollection of anecdotes in front of a glass of wine. I unfortunately must have drunk a glass too many, since I promised that I would not broadcast the many stories I heard. Hence I am afraid I cannot share them with you here. But if the evening convinced me of something, it is that Zweig should really write a biography - or actually two, since apparently the life of Zweig's father is even more astonishing than his own !