i mean, i tweet, but i don't have, like, a nicholas christakis account.james and i share that account. but my point is that that's a different kind of interpersonal influence than the kind we're speaking about right now. so the kind that i'm interested in is the kind of face-to-face kind of way in which we affect each other. so it's the difference between the effect that, sort of, president obama has on his daughters versus the effect president obama has on all kids in the country, right? so the president can get up and everyone will pay attention to him and he'll make some kind of pronouncement. he might have a weak effect over hundreds of thousands of people, or he could have a very strong, powerful, direct effect over someone he knows personally, face-to-face. and so both are important, but, um... i can actually illustrate this with a little analogy, okay? okay, so people have asked us how it is the case that there is... how there can be a kind of interpersonal influence when it comes to weight gain and obesity, for example, even though the models on t