Five years ago, a team of researchers from Google announced a remarkable achievement in one of the world's top scientific journals, Nature. Without needing the results of a single medical check-up, they were nevertheless able to track the spread of influenza across the US. What's more, they could do it more quickly than the Centers for Disease Control and Prevention (CDC). Google's tracking had only a day's delay, compared with the week or more it took for the CDC to assemble a picture based on reports from doctors' surgeries. Google was faster because it was tracking the outbreak by finding a correlation between what people searched for online and whether they had flu symptoms. Not only was "Google Flu Trends" quick, accurate and cheap, it was theory-free. Google's engineers didn't bother to develop a hypothesis about what search terms – "flu symptoms" or "pharmacies near me" – might be correlated with the spread of the disease itself.

When American novelist David Foster Wallace delivered the commencement address at Kenyon College in 2005, he urged the graduating class to "exercise some control over how and what you think." If you don't at least try to regulate your thoughts and behaviors, Wallace cautioned, you will go through life "dead, unconscious, a slave to your head." Wallace himself long suffered with unwanted negative thoughts and crippling self-doubt--and took his own life three years after that speech. But can our mind become a "terrible master," as Wallace described? Kessler, the former commissioner of the U.S. Food and Drug Administration, has considered that question for the past two decades, studying how substances such as food, alcohol and tobacco can hijack our brain chemistry and compel us to act against our own best intentions--bingeing on brownies, booze or cigarettes.

"Smarter Faster Better: The Secrets of Being Productive in Life and Business" (Random House) is Charles Duhigg's follow-up to his best-selling "The Power of Habit: Why We Do What We Do in Life and Business," which was published in 2012. The new book, like its predecessor, has a format that's familiar in contemporary nonfiction: exemplary tales interpolated with a little social and cognitive science. The purpose of the tales is to create entertaining human-interest narratives; the purpose of the science is to help the author pick out a replicable feature of those narratives for readers to emulate. What enabled the pilot to land the badly damaged plane? How did the academic dropout with anxiety disorder become a champion poker player? What made "West Side Story" and Disney's "Frozen" into mega-hits?