in one sense these works appear to be "unfinished" with the composer handing them on to the performer "more or less like the components of a construction kit ."such uncertainly of form is a central characteristic of Eco's "open works" but this is an uncertainly that is to be celebrated rather than condemned.such works'while being organically complete 'maintain both a context and formal elements that are open to continuous revision and regeneration'Their internal mobility of form sets up the possibility of dialog or interaction between author'performer and audience.The works take on a dynamic openness."a kaleidoscopic capacity to suggest themselves in constandly renewed aspects to the consumer."