The distinction between a context of discovery and one of justification with regard to scientific activities (hereafter: DJ distinction) has developed a remarkable life of its own in 20th century philosophy of science and beyond, eventually becoming an influential conceptual device. Hans Reichenbach's exposition provided the major starting point for a broad discussion, within which several versions of the distinction emerged.¹ One can safely state that no such thing as one single proper DJ distinction exists. Rather, it implies a richness of different perspectives on the relation between historical and philosophical approaches to science.