Self-help advice reflects the beliefs and priorities of the era that spawned it. Illustration by Nishant Choksi Audio: Listen to this story. To hear more feature stories, download the Audm app for your iPhone.

Happy New Year, you! Now that the champagne has gone flat and the Christmas tree is off to be mulched, it’s time to turn your thoughts to the months ahead. 2017 was a pustule of a year, politically and personally; the general anxiety around the degradation of American democracy made it hard to get much done. That’s O.K., though, because you’ve made new resolutions for 2018, and the first one is not to make resolutions. Instead, you’re going to “set goals,” in the terminology of the productivity guru Tim Ferriss—preferably ones that are measurable and have timelines, so you can keep track of your success. Apps like Lifetick or Joe’s Goals will help by keeping you organized and allowing you to share your progress on social media; a little gloating does wonders for self-motivation (unless, of course, one of your goals is to spend less time on social media). Once your goals are in place, it might be smart to design a methodology that will encourage you to accomplish them. Charles Duhigg, the author of “The Power of Habit,” recommends a three-step self-conditioning process. You want to get to the gym more? Pick a cue (sneakers by the door); choose a reward that will motivate you to act on it (a piece of chocolate); execute. Bravo! You are now Pavlov and his dog.

But soon enough February will come, mid-winter doldrums will set in, and you’ll start to slide. Not to worry. Jane McGonigal’s “SuperBetter” tells you how to gamify your way back from the edge with the help of video-game-inspired techniques like finding “allies” and collecting motivational “power-ups”; and Angela Duckworth’s “Grit: The Power of Passion and Perseverance” reminds you that persistence makes all the difference when the going gets rough. Duckworth doesn’t think you need talent in order to become, as another of Duhigg’s books puts it, “Smarter Better Faster,” and neither do any of these other experts. According to their systems, anyone can learn to be more efficient, more focussed, more effective in the pursuit of happiness and, that most hallowed of modern traits, productivity. And if you can’t, well, that’s on you.

Self-help advice tends to reflect the beliefs and priorities of the era that spawns it. A decade ago, the reigning champion of the genre was “The Secret,” published in 2006 by an Australian, Rhonda Byrne. Like Norman Vincent Peale before her, Byrne combined a literal interpretation of select verses from the Christian Bible—notably Matthew 21:22, “Whatsoever ye shall ask in prayer, ye shall receive”—with the acquisitive gospel of positive thinking. If you sent a wish out into the universe with enough faith, she told her readers, it could come to pass. Want to find a husband? Clean out a closet for the man of your dreams and imagine him hanging up his ties. Want to get rid of your glasses? Picture yourself acing your next vision exam and kiss those progressive lenses goodbye. In retrospect, “The Secret,” which sold more than twenty million copies worldwide, seems a testament to the predatory optimism that characterized the years leading up to the financial crisis. People dreamed big, and, in a day of easy money, found that their dreams could come true. Then the global economy crashed, and we were shaken violently awake—at least for a time.

In our current era of non-stop technological innovation, fuzzy wishful thinking has yielded to the hard doctrine of personal optimization. Self-help gurus need not be charlatans peddling snake oil. Many are psychologists with impressive academic pedigrees and a commitment to scientific methodologies, or tech entrepreneurs with enviable records of success in life and business. What they’re selling is metrics. It’s no longer enough to imagine our way to a better state of body or mind. We must now chart our progress, count our steps, log our sleep rhythms, tweak our diets, record our negative thoughts—then analyze the data, recalibrate, and repeat.

Carl Cederström and André Spicer, business-school professors in a field called “organization studies,” set out to do all that and more in their recent book, “Desperately Seeking Self-Improvement: A Year Inside the Optimization Movement” (OR Books), a comically committed exploration of current life-hacking wisdom in areas ranging from athletic and intellectual prowess to spirituality, creativity, wealth, and pleasure. Cederström, an enthusiastic Swede, and Spicer, a melancholy New Zealander, want to understand the lengths to which people will go to transform themselves into superior beings, and to examine the methods that they use. In their previous book, “The Wellness Syndrome,” the authors followed health nuts who were determined to meditate and exercise their way to enlightenment. This time, in the spirit of George Plimpton’s brand of participatory journalism, they’ve become their own test cases, embarking on a yearlong program in which they target a new area of the self to improve each month. They bulk up at Cross Fit, go on the Master Cleanse liquid diet, try mindfulness and yoga, consult therapists and career coaches, sample prostate vibrators, attempt standup comedy, and attend a masculinity-boosting workshop that involves screaming and weeping naked in the woods. Even their book’s format—entries of the diary that each keeps to record and reflect on his endeavors—is relevant to their mission, considering that daily journaling is recommended in Tim Ferriss’s “Tools of Titans: The Tactics, Routines, and Habits of Billionaires, Icons, and World-Class Performers.”

Many of the tasks that Cederström and Spicer assign themselves have a double-dare quality whose cost-benefit value seems questionable, like memorizing the first thousand digits of pi during Brain Month in order to improve mental acuity. But others inspire the same niggling whisper of self-doubt as Instagram posts of green juice: Should I be doing that, too? I confess to feeling a pang of jealousy when Cederström produces a complete book manuscript in a euphoric amphetamine rush induced by study drugs during Productivity Month—and a surge of Schadenfreude when it’s rejected by his baffled publisher.

“In a consumerist society, we are not meant to buy one pair of jeans and then be satisfied,” Cederström and Spicer write, and the same, they think, is true of self-improvement. We are being sold on the need to upgrade all parts of ourselves, all at once, including parts that we did not previously know needed upgrading. (This may explain Yoni eggs, stone vaginal inserts that purport to strengthen women’s pelvic-floor muscles and take away “negative energy.” Gwyneth Paltrow’s Web site, Goop, offers them in both jade and rose quartz.) There is a great deal of money to be made by those who diagnose and treat our fears of inadequacy; Cederström and Spicer estimate that the self-improvement industry takes in ten billion dollars a year. (They report that they each spent more than ten thousand dollars, not to mention thousands of hours, on their own quests.) The good life may have sufficed for Plato and Aristotle, but it is no longer enough. “We are under pressure to show that we know how to lead the perfect life,” Cederström and Spicer write.

Where success can be measured with increasing accuracy, so, too, can failure. On the other side of self-improvement, Cederström and Spicer have discovered, is a sense not simply of inadequacy but of fraudulence. In December, with the end of their project approaching, Spicer reflects that he has spent the year focussing on himself to the exclusion of everything, and everyone, else in his life. His wife is due to give birth to their second child in a few days; their relationship is not at its best. And yet, he writes, “I could not think of another year I spent more of my time doing things that were not me at all.” He doesn’t feel like a better version of himself. He doesn’t even feel like himself. He has been like a man possessed: “If it wasn’t me, who was it then?”