Ron and I became friends when I was visiting in Bloomington in the all too eventful year 1968-69.  Everything seemed to be changing that year, but there were constants -- for Ron and me, our friendship turned out to be one of those constants, in both our personal and philosophical life.  We never lived in the same town again, so each meeting was especially important.  It felt quite often as if we were playing intellectual tennis, as we reacted to each other about realism, perspectives, and representation.  Our long and close friendship for these past five decades is a treasure I will go on cherishing.

Bas van Fraassen