A serendipity can be defined as an unexpected happiness. During a low time in my life that seemed endless, the playing of the Pachelbel Cannon on a Sunday afternoon charged my inner being with the certainty that, eventually, all would be well.

Years later on an afternoon in Marseille, France, my husband and I searched for a place to eat. We had arrived in the French coastal city to spend one night before heading out early the next day on a ferry. It would take us across the Mediterranean to the historic city of Algiers.

We wanted only to eat and collapse in bed back in our hotel. I was a newly assigned junior economic officer at the U.S. Embassy in Algiers. I wandered in the anxious space one inhabits before entering unknown territory. Could I handle this assignment? What about the threatened insurgency in Algeria? The Embassy had recently evacuated all minor dependents because of terrorist threats.

This being Europe, not many restaurants were open in the afternoon. We stumbled onto a McDonald’s that, like its prototypes everywhere, was open all day.

We went in, bought our food, and settled upstairs in the almost empty restaurant. Then we heard the sounds of classical music. The McDonald’s may have been American-franchised, but this was France. A classical pianist played below. We enjoyed our Big Macs within the pleasant atmosphere of Mozart and Beethoven.

Yes, in a couple of days we would climb the hill out of Algiers’ Casbah and follow the narrow streets into an uncertain future in that troubled land. But for the moment, the music calmed my anxieties and prepared me to cope with what lay ahead.