American political scientist Robert Putnam wasn’t the first person to recognize that social capital – the relationships between people that allow communities to function well – is the grease that oils the wheels of society. But by publishing Bowling Alone, he moved the debate from one primarily concerned with family and individual relationships one that studied the social capital generated by people’s engagement with the civic life.

Putnam drew heavily on the critical thinking skill of interpretation in shaping his work. He took fresh looks at the meaning of...