Could Anyone Justifiably Believe Epiphenomenalism?

Epiphenomenalism claims that all conscious events are caused immediately by brain events, and no conscious events cause brain events. In order to have a justified belief in a theory someone needs a justified belief that it or some higher-level theory predicts certain events and those events occurred. To have either of the latter beliefs we depend ultimately on the evidence of apparent experience, memory, and testimony, which is credible in the absence of defeaters; it is an undermining defeater to a belief produced by apparent memory that it was not caused by a past belief, and to a belief produced by apparent testimony that it was not caused by an intention to say what the speaker believes. A justified belief in epiphenomenalism requires either evidence about when conscious events occurred or evidence about what some theory that brain events are caused solely by physical events predicts, but epiphenomenalism rules out the availability of the evidence of apparent memory and testimony on these matters. Hence only a rare individual scientist who could hold in her mind at one time the proof that a theory makes certain predictions could have a justified belief that epiphenomenalism is true. It follows that recent neurophysiological work in the tradition of Libet has no tendency whatever to provide a justified belief in epiphenomenalism.