Blasse's Pandora's box

Upon his retirement from science Blasse wrote a paper (Blasse, J. Lumin. 72-74 (1997) 129) addressing unsolved problems in explaining luminescence phenomena of classical phosphors. He used the metaphor of Pandora's box. A box full of disaster that should remain closed. Yet, Blasse did open that box and therewith spread the unsolved problems...