Answer

My response is that this is the way of mind-numbing babblers. If they have an argument, let them make it and point out an error in my arguments. General declarations about the reasons for my failures are an evasion used by someone who has no arguments (because he can’t have any).
And regarding this claim itself, which is beside the point, it depends on the nature of the critique. There are critiques that concern the fundamental structure of a field, and they do not depend on familiarity with the details. They can be raised a priori. Suppose some philosopher criticizes the principle of causality accepted in physics. Does he need to know the various fields of physics and all the findings in order to present his critique? He hardly needs to know anything.
And above all, there is neither any need nor any possibility of becoming acquainted with postmodern thought, because there is no such thing. There are postmodern texts, but not postmodern thought. As I explained in my lecture, “Is There Religious Postmodernism?,” such texts are made up of two components, in varying proportions: 1. Arguments that can be formulated in completely modernist language. 2. Nonsense. The value of such a text depends on the proportion of component 1 to component 2. Either way, its value always lies in its non-postmodern component.