From Mises Wiki, the global repository of classical-liberal thought
Pseudoskepticism is a type of unscientific attitude that manifests itself in a person's denial of the truth of an assertion, while remaining unwilling to engage in constructive argumentation on the subject. The pseudoskepticist refuses to offer any counterevidence, to point out any flaws or shortcomings in the evidence offered in support of the assertion, or to make any effort to refute the person's logic. He states that the burden of proof is on the person making the assertion, which is true enough. But what makes him a pseudoskepticist is that he pays no attention to efforts to meet that burden of proof, dismissing them out of hand as inadequate, without saying why they are inadequate. This is similar or identical to argumentum ad lapidem.