So far we have been chiefly concerned with the practices of masking: the various social and theatrical events for which masks were worn. But masking at this period was not only an activity; it was also a subject for critical comment and scholarly study, a topic for moral argument, and a fruitful metaphorical concept. Contemporary ideas about masks and masking form an important, though frequently nebulous and imprecise, context to the activity itself. The relationship of theory to practice is often problematic. Although medieval debate about masking can be directed at, or sparked off by contemporary practices, it as often appears to be purely speculative, historical, or theoretical, existing alongside but not necessarily in any significant relation to masking practice. While what maskers did can certainly be illuminated by what was thought about masking, the light that is thrown is often oblique, shaded, and flickering.