Aaron Becker learned while living in Granada, Spain, that many of the city’s stone churches had at one point been mosques and, before that, Roman ruins. Which got him thinking: What wisdom can something as still as a rock share with the rest of us? While he could only guess at the answer, he does have some experience with these ancient fragments of earth. After all, the house where he grew up in Baltimore was built from, you guessed it, stone. Aaron Becker lives in western Massachusetts.