Glenn Greenwald was one of the first reporters to see — and write about — the Edward Snowden files, with their revelations about the United States’ extensive surveillance of private citizens. In this searing talk, Greenwald makes the case for why you need to care about privacy, even if you’re “not doing anything you need to hide.”

“When we’re in a state where we can be monitored, where we can be watched, our behavior changes dramatically. The range of behavioral options that we consider when we think we’re being watched severely reduce. When somebody knows that they might be watched, the behavior they engage in is vastly more conformist and compliant,” he said. “A society in which people can be monitored at all times is a society that breeds conformity, obedience and submission, which is why every tyrant, from the most overt to the most subtle craves that system.”