 Here, then, is a summary of this complex dialectic: the argument from hallucination seems to disprove naive realism, but the naive realist appeals to disjunctivism in response. However, the causal argument puts pressure on disjunctivism, by supporting the common kind assumption. In response, the naive realist rejects the key principle of this argument (Causal Principle 1). But then a two-stage argument consisting of the reverse causal argument and the screening-off problem attempts to show that: (1) the fundamental kind of experience present in hallucination is also present in causally matching veridical experience, and (2) this undermines the naive realist idea that the character of veridical experience is shaped by the directly presented world. In response, Martin accepts a form of naive realism which embraces disjunctivism (in the form of the claim that causally matching veridical and hallucinatory experiences are fundamentally different). But which also accepts (as per the reverse causal argument) that there is a common element across the cases, for the hallucinatory kind is present in veridical cases too. But since he conceives of this common element in a derivative, and purely negative epistemic way, he blocks the argument at the second stage, rejecting screening off.