Having led The Environmental Defense Fund for more than 3 decades, he knows its history. “The founding motto, informally, of EDF was ‘Sue the bastards,” he recalls. Today its guideline is, “Environmental problems are solvable if people would just get on with solving them and stop shouting at each other.” Has he mellowed or matured? Fighting climate change in the age of Scott Pruitt. Plus music from Gregorio Uribe and Solange Pratt.

•  PERSON: Prof. Charlie Walker
•  PLACE: Maritime Rowing Club
•  THING: Methane Detector
•  RANDY’S PLACE: Bear Mountain