One of the underlying problems in Habermas's debate with Rawls which we surveyed in Chapter Seven is the notion of the political and its connections with the metaphysical. We need now in our last chapter, Chapter Eight, to look at both the metaphysical and the political more closely.

The Metaphysical and the Political

The key to this important distinction lies in the conflating of “the metaphysical” with the “comprehensive.” But, as we already saw in a preliminary way in the preceding chapter, these two terms need untangling.

The Comprehensive as the Metaphysical

Habermas seems to take the political as necessarily involving, among other elements, metaphysical ones. This is not Rawls's conception. For Rawls takes the political as separable from the metaphysical. Consequently, Rawls holds against Habermas that justice can be insulated from the metaphysical by being construed as pre-eminently political.

Rawls's idea here is that the metaphysical comprises any set of world views or “comprehensive doctrines” whether religious or secular. Modern societies show the presence of a plurality of such views, a point that both Max Weber and John Dewey stressed. In order, however, for a society to be based upon a proper understanding of social justice, the scope for disagreement must be narrowed as much as possible.