by lil

For Kaku, the brain is a computer made of meat, and understanding the mind is just a really, really hard engineering problem.

but

The problem is that we still don’t have much in the way of a working model of consciousness. With a physicist’s eye for economy, Kaku tries to provide one through what he calls a “space-time theory.” It’s a model of consciousness with a graded scale of awareness based on the number of feedback loops between environment and organism. Thus, in Kaku’s view, a thermostat has the lowest possible level of consciousness while humans, with our ability to move through space and project ourselves mentally backward and forward in time, represent the highest level currently known.

Interesting! My favourite line in the book review:

it seems to me that Kaku has taken a metaphor and mistaken it for a mechanism.

Even so - Perhaps consciousness is a spectrum ranging from minimal (thermometer) to maximal feedback loops between the environment and the organism. And also the ability to examine, question, doubt, or ignore that feedback.