On Monday, John went to the mall. John left Green’s Grocery at 7:47 AM and drove home in his 2007 Honda Pilot. John forgot his blue umbrella in the store. That night John’s neighbor Martha, a retired engineer who lives down the block from him, called him. Martha had found the umbrella and was coming to return it. Is that a miracle? Or a largely predictable outcome? The answer depends on which of the many coincidences we consider.

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