Our world revolves. Not just literally, as it does around the sun, but in nature’s every aspect. Seasons cycle into each other (though more erratically each year), waves trace and retrace the beaches with the shifting tide, flowers open, close, and turn to follow the path of the sun. Even we are governed by these circular natural systems. Maintenance of our circadian rhythms, a human connection to light, is so essential to our health that it is a required element in many contemporary building codes.