When I visited West Philadelphia’s Employment, Advancement, and Retention Network Center in the spring of 2013, its tall white walls were covered with green and yellow stars, each bearing the name of an Achiever of the Year or a Hall of Famer — welfare recipients who had landed a job or kept one for at least six months. Running high along one wall was a slogan — “Positive thoughts attract Positive results. And We are Positive about that!” — surrounded by plus signs that bore inspirational quotations. In a corner of the room I found a yellow flyer taped to a concrete…