The words "left" and "right" are flimsy and one-dimensional for this purpose, but the basic dichotomy they're referring to in this context has deep roots in his

The words "left" and "right" are flimsy and one-dimensional for this purpose, but the basic dichotomy they're referring to in this context has deep roots in historical thinking: whether it's right for people to have whatever they can get vs what they need— with the choice of moral framework indicating who "deserves" status and advantages; the former being the meritocratic/libertarian/objectivist sense, or the latter the communist/liberal/christian sense. In either case "right" and "left" are poorly matched, but come on, you know what they're talking about.