In a sloppy but understandable attempt at satire, Justine Sacco tweeted: “Going to Africa. Hope I don’t get AIDS. Just kidding. I’m white!” Then she got on a long plane ride to South Africa. During the flight her tweet went viral, enraging the easily enraged bastions of social media and catapulting the hashtag #HasJustineLandedYet around the world. When she landed in Johannesburg she was out of a job and in the throes of a scorching, unmerciful online public shaming.

I was on Twitter the day #HasJustineLandedYet was in progress. When I figured out what it was about, I probably chuckled, thought “Sucks to be her…” and clicked elsewhere. But Justine, freshly captive prey of the collective shaming committee that is the Internet, wasn’t allowed to move on. The invisible, crushing weight of public opinion had pinned her to her momentary mistake. Jon Ronson interviewed her about this experience for his new book So You’ve Been Publicly Shamed, an eye-opening panorama of the dark, menacing, deceptively fleeting phenomenon of online shaming. His dissection of these digital witch hunts led him on a listening tour of other recent victims like Jonah Lehrer, Lindsay Stone, and Adria Richards, who were, months or years after their respective ordeals, still haunted by a modern twist on PTSD. Call it Post Traumatic Shaming Disorder.

Before her Twitstorm, Sacco was director of communications at IAC, the parent company of OkCupid, whose co-founder Christian Rudder wrote another fascinating book recently released called Dataclysm: Who We Are (When We Think No One’s Looking). I read Dataclysm right after So You’ve Been Publicly Shamed, which was fortuitous not only because both books feature the Justine Sacco saga, but because Rudder’s deep dive into the data about our online selves—dating site profiles and otherwise—weaved perfectly with Ronson’s closely observed stories of public shaming. And the joint conclusion we can make doesn’t look good.

The “when we think no one’s looking” part of Rudder’s title is key here. Dataclysm focuses on OkCupid users, but he might as well be writing about Us. “So much of what makes the Internet useful for communication—asynchrony, anonymity, escapism, a lack of central authority—also makes it frightening,” he writes. Nearly everything we do online we do when no one’s looking. Even if a real name and picture is attached to a Twitter profile viciously trolling the Justine Saccos of the web, the ramifications are few. Kill that account, another will pop up.

The really interesting stuff, then, is what lies beneath the cultivated online personas, the stuff we don’t have incentive to lie about or craft for a particular purpose. What if your Google searches were made public? (Because they basically are.) Our searches would paint a much finer (though not prettier) portrait of ourselves than our Facebook posts, try as we might to convince ourselves otherwise.

Compared to Facebook, Rudder writes, which is “compulsively networked” and rich with interconnected data, dating sites like OkCupid pull people away from their inner circle and into an intentional solitude: “Your experience is just you and the people you choose to be with; and what you do is secret. Often the very fact that you have an account—let alone what you do with it—is unknown to your friends. So people can act on attitudes and desires relatively free from social pressure.”

OkCupid users are prompted to answer questions the site’s algorithms use to find other compatible users. The answers are confidential, so like Google searches they tell a more nuanced story about the user than whatever they write in their OkCupid self-summary. And yet there persists a wide discrepancy between what people say they believe—what they tell the algorithm—and how they actually behave on the site. The stats on who they chat with, for how long, and whether an in-person date occurs end up revealing more about a user’s preferences than their expressed beliefs.

Does the same apply to the hordes of people behind #HasJustineLandedYet? They might not be quite as evil and sadistic in real life as they seem online, but they can afford to play-act in whatever persona they’re cultivating because they’re protected by distance: abstractly, the virtual world being a different, cloudier dimension than the physical one; but also concretely, in that the odds of bumping into your shaming victim on the street is practically nil.

So You’ve Been Publicly Shamed and Dataclysm travel on the same track, but start out in opposite directions. Both concern themselves with the real-life implications of desire, how it’s wielded and to what end. Desiring companionship, love, or sex, OkCupid users seek opportunities to encounter whatever it is they’re looking for, personal fulfillment usually being the ultimate goal. Ronson’s case studies, heading the other way, illustrate the deviousness of desire—when on the road to euphoria we carelessly or even intentionally run down whoever gets in our way. “There is strength in collective guilt,” Rudder writes, “and guilt is diffused in the sharing. Extirpate the Other and make yourselves whole again.”

Yet neither book is as depressing as I’ve portrayed them. Dataclysm wades into a bevy of interesting data-driven topics, like the most common and uncommon words used in OkCupid profiles based on race and gender, how beauty gives people a quantifiable edge, and the emergence of digital communities. And Ronson’s journey leads to a host of stories, historical and contemporary, that lend depth and nuance to a social phenomenon desperately in need of them.

Above all, these books should make us think twice before hitting Send. “If you’re reading a popular science book about Big Data and all its portents,” writes Rudder, “rest assured the data in it is you.” Whether we’re chirping into a stupid hashtag or perusing profile pics in search of The One, someone is always watching.