Now let's look at a basic fact of our digital lives, online ads. Right? We kind of dismiss them. They seem crude, ineffective. We've all had the experience of being followed on the web by an ad based on something we searched or read. You know, you look up a pair of boots and for a week, those boots are following you around everywhere you go. Even after you succumb and buy them, they're still following you around. We're kind of inured to that kind of basic, cheap manipulation. We roll our eyes and we think, "You know what? These things don't work." Except, online, the digital technologies are not just ads. Now, to understand that, let's think of a physical world example. You know how, at the checkout counters at supermarkets, near the cashier, there's candy and gum at the eye level of kids? That's designed to make them whine at their parents just as the parents are about to sort of check out. Now, that's a persuasion architecture. It's not nice, but it kind of works. That's why you see it in every supermarket. Now, in the physical world, such persuasion architectures are kind of limited, because you can only put so many things by the cashier. Right? And the candy and gum, it's the same for everyone, even though it mostly works only for people who have whiny little humans beside them. In the physical world, we live with those limitations.