Perception, cognition, and a little detection

''Radiant Cool" is a campus thriller. The flamboyant professor Maxwell Grue has disappeared. His graduate student Miranda Sharpe discovers that he was close to formulating a novel theory of consciousness. Naturally she suspects foul play. Miranda enlists the help of Grue's colleague ''Dan Lloyd" (who, like the book's author, is a philosophy professor at nearby Trinity College). Together they foil a dastardly KGB plot to hijack both the Internet and the Grue/Lloyd theory, which would have allowed them to control global consciousness, hence the world.

Part 2 of ''Radiant Cool," a hundred pages of straight exposition, is less fun but much meatier. Lloyd's theory is a scientific version of Edmund Husserl's phenomenology. The basis of this method is a relentless attention to context, especially temporal context. We are not, phenomenologists point out, a collection of independent instruments reporting to an overseer called ''consciousness" or ''mind." On the contrary, it is not possible to perceive an object, event, or other stimulus with anything less than one's entire self. This means that by the same act with which we perceive something we interpret it, i.e., situate in some relation to the rest of our experience. And immediately, the experience of having experienced it in this instant, with whatever consequences (if any) that entails, becomes part of our experience, which is then brought to bear in the next instant.

It's not hard to see that this can get complicated, i.e., mathematical. Lloyd and others have adapted two of the newest techniques in brain science -- multidimensional scaling (MDS) and functional magnetic resonance imaging (fMRI) -- to the phenomenological method. Phenomenology demonstrates that the mind is a system in which ''the action of the entire network depends on the interaction of all its parts." To map such a network involves representing each of these parts as a separate dimension. The mathematics of MDS makes this possible, while fMRI, which measures what's happening in each part of an active brain, supplies the data.

As Lloyd's final pages make clear, consciousness may in principle be partly opaque. But by then, you'll see a lot farther into it than before.