Christopher Wylie

In an era of whistle-blowers, Christopher Wylie wields a bullhorn. The 28-year-old data genius devised the ideas behind Cambridge Analytica, the firm that took credit for influencing the Brexit vote and the online success of Donald Trump’s 2016 campaign. His revelations in March about the firm’s allegedly nefarious means of acquiring social-media data most of us thought reasonably private sent Facebook reeling into a crisis and added another twist to the still incomplete story of America’s election.

But Wylie’s impact goes far beyond those things. For years, the growing power of large technology companies has created a generalized anxiety—their ability to influence whom we vote for, what we believe, when we buy and even how we feel is disquieting to many of us. This anxiety is often fleeting and hard to grasp. Wylie crystallized it, showing that, yes, this unregulated power is shaping our lives and our world. In doing so, he has given us a chance to do something about it before it’s too late.

Vella is a TIME executive editor