This paper gives recognition to the immense expansion in psychoanalytic thinking of recent decades. However, the implication (of the title of the panel of which this paper was a part) that advances in knowledge readily translate into advances in technique is seriously challenged, though in a playful format. The format pursues 4 variations on the title theme: 1) I could not know then what I know now; 2) If I knew then what I know now, I would not have been able to use it; 3) I did know then what I know now; and 4) If I knew now what I knew then….