Suggesting the term of a “method of insulation,” this paper analyzes a development that characterizes Rawls’s thought after the publication of Theory. He sought to strengthen his theory of justice by seemingly weakening it, that is, by reducing its philosophical – and especially metaphysical – core commitments to what is absolutely essential for the theoretical enterprise to be successful, aiming at “doctrinal autonomy” and a “free-standing” conception of justice. In reconstructing the main “declarations of philosophical independence” until Political Liberalism, the major achievements but also the problems of this view are discussed. For there came a point at which the method of insulation endangered rather than strengthened the autonomous normative standing of Rawls’s “political” conception of justice.