A recent NPR story detailed a research report that essentially documented what my mother taught me from the time I was pedaling my tricycle and learning two-syllable words: how we treat one another really matters. Somehow mapping (and this investigate feat is a marvel) 32 years of face-to-face interactions among approximately 5,000 people in one small town, the lead researcher Nicholas Christakis concluded that emotion (whether positive or negative) moves from one person to another like a contagion. If we engage someone (a friend, co-worker, stranger at a coffee shop) with kindness or joy, then that person is likely to swell with kindness or joy themselves. The same happens in reverse. If we are angry, sullen or demeaning, then we strike the match; and these harmful emotions take on a life of their own.

Most of this seems intuitive. However, the report’s real shocker comes from the revelation regarding how far one’s impact extends. If we begin to express happiness, for instance, a friend who lives in close proximity has a 25% chance of becoming happier too. We affect others not only in person-to-person exchanges but also via our vast tentacles of relationship. This explains in part why social media is so powerful (and also so destructive). “Emotions can spread through social networks,” the story explains, “almost like the flu or cold.”

We all know people who are real downers. It’s not merely that they struggle or need help (that’s being human and true of all of us at some point), but rather that these negative folks perpetually foster anger or criticism, despair or judgment. They seek out these caustic energies. They nurture them. They live as though they require a toxic habitat as much as a fish needs water. And the more we are around such people, the more we find ourselves pulled into the cesspool ourselves.

The good news here, though, is that we actually have the capacity to ignite a wave of joy or hope. We can, with our ordinary, persistent acts of generosity and kindness, create ever expanding circles of welcome, of friendship, of understanding, of respect, of deep humanness. No kind word is ever spoken in vain. Every ounce of energy expended toward another, no matter how seemingly insignificant, carries the possibility of profound transformation. We can be revolutionaries, inciting a revolution of goodness.