When news of the study spread in June, people were outraged. (Hancock says he was still receiving physical threats in response to the study as recently as last week.) Hancock now says he's prioritizing conversations—with academics, policy makers, and others—to move forward so that people "don't feel wronged or upset" by this kind of work. It's a process he expects will take years. The emails he gets these days are still angry, but the stream of them has slowed.

I first asked Hancock to talk about the experiment back in June, but he wanted to wait until some of the media attention waned. We spoke for the first time this week.

* * *

"You have this algorithm which is a weird thing that people don't really understand," Hancock told me. "And we haven't discussed it as a society very much."

Hancock is still reluctant to draw too many conclusions about what he learned in the aftermath of the Facebook study. He declined to talk on-record about what he might do differently next time, or to detail advice he'd have for someone conducting a similar experiment.

One of Hancock's main areas of research has to do with "deception and its detection," according to his university website, a detail that people have asked him about, he says. "'You study deception and obviously you were super deceptive in this study'—That has come up in a few emails," he said.

"There is a trust issue around new technologies," he continued, "It goes back to Socrates and his distrust of the alphabet, [the idea that] writing would lead to us to become mindless ... It's the same fear, I think. 'Because I can't see you, you're going to manipulate me, you're going to deceive me.' There could be a connection there where there's a larger trust issue around technology." For now, Hancock says, he just wants to better grasp the way that people are thinking about algorithms. Understanding expectations will help him and others figure out the ethical ways to tinker with the streams of information that reach them.

"For me, since the Facebook study controversy and the reaction, we've just started asking in the lab, 'Well, what are people's mental models for how a News Feed is created? How a Google search list is created? How iTunes rankings for songs work?'" he said. "When you step back, it's almost like every large company that is consumer-facing has algorithms working to present its data or products to the users. It's a huge thing."

So huge, and so much a part of the way the Internet works, Hancock suggests, that we may have passed the point where it's possible for people to reasonably expect they'd have to give consent before a corporation messes with the algorithmic filters that affect the information they see online.

That issue of consent was one of the biggest questions to emerge from the Facebook study. Is it enough to only notify users in a terms-of-service agreement that they might be subject to the experimental whims of a company? (It appears the Facebook study may not have even done that.)