Their big idea is that most brain processing occurs at a subconscious level, that intuitions are subconscious processes which lead (opaquely) to conscious conclusions (metarepresentations), that reasoning is an opaque process associating such metarepresentations with other metarepresentations allowing us to justify our actions to ourselves and others, mostly in reputational support.
This social rationale for reasoning explains why the accounts we give ourselves for our actions are often quite superficial and weak while in justifying ourselves to others we often strengthen our reasons through dialogue. And also that in most cases our reasoning is ex post facto.
The confabulatory rationale for reason is something designers of neural network AI systems will have to take on board. Since, according to the authors, our reasoning powers evolved for public relations purposes, justifications for our underlying evolutionary drives, expect the corresponding motivations of corporeal AI systems to be rather salient to their conversational capabilities.
The book is marred by its style of writing, too keen to show off its authors' liberal susceptibilities, moral qualities and faux-affability. I did not feel on their team. The book is also way too discursive, reminiscent of late-Dennett. They would probably think this a compliment.
I was quite impressed with this book for a while, as Rodrik explained that globalised capital really 'wants' a global 'democratic' institutional framework to ensure its continued replication .. and that nation states and pesky local interests (eg the working classes) get in the way and need to be shunted aside.
His solution was a return to a (modified) Bretton Woods arrangement of more enlightened nation states. My suspension of disbelief finally crumbled when he started advocating unrestricted immigration and the removal of border controls as a major driver of future economic growth. And this is the guy who accuses others of believing more in their oversimplified economic models than facts on the ground!
Even Hive Mind, with its hand-wringing cop-outs, was a lot better than this.