Comment by zoogeny

I was considering your explicit "material -> conscious -> ideas -> material" description. It feels more correct when you say he considers a range of possibilities that connect these, not explicit causality.

My take away was that he sees a mystery in the connections between these things (physical world, consciousness, ideas) that hints at some missing ideas in our conceptions of these things. But he clearly wants to avoid that mystery allowing what he calls out as "vague" answers to the question (mostly religious dogmatic certainties).