epiphenomenalism

I was reading V. S. Ramachandran's great book A Brief Tour of Human Consciousness, where he mentions epiphenomenalism. He defines it to mean that a quale is a product of a brain event, but is causally inefficacious with respect to that event. It may well be efficacious to other parts of the...

I posted a question about epiphenomenalism over in the Science forum, but I don't want to hijack that thread by pressing the issue. I've read three or four descriptions of epiphenomenalism in the past couple of days. The concept seems utterly incoherent. What am I missing? ~~ Paul