Epidaurus

Amphitheatre does not mean a space where people speak, but one where many see. A sacred word will silence those assembled there; it need not even be a word, sometimes a wordless gesture is all it takes to render them silent: a kind of ritualized mime, and silence overtakes the collective hearing as all eyes focus as one. Transfixed, one's organs are at peace: this is healing. Sometimes music is all it takes, and nestled in the hollow of hearing the orchestra listens and watches, the assembled throng heals itself by listening to its own harmony, observing it in silence, nestled inside the immense marble ear; what it hears is its own social contract.

-- Michel Serres, The Five Senses, tr. Margaret Sankey and Peter Cowley