In situations like those, the instinct to say “no” serves us well. The psychologist Roy Baumeister refers to this phenomenon as “bad is stronger than good.” In a paper with the same title, he writes, “Organisms that were better attuned to bad things would have been more likely to survive threats. Survival requires urgent attention to possible bad outcomes, but it is less urgent with regard to good ones.”

There is a difference, however, between surviving and thriving. Because our survival is no longer under constant threat, many more of us have the opportunity to focus on thriving. The problem with “no” as a starting place is that it polarizes, prompts defensiveness and shuts down innovation, collaboration and connection.

The psychologist and researcher John Gottman has famously found that when the ratio of positive to negative interactions in a marriage falls below five to one, divorce is far more likely. Negativity, in short, can be potent poison, and its effects are long lasting and often pernicious.

By contrast, starting with “yes” energizes, creates safety and trust and fuels creativity. I learned this viscerally during an improvisation workshop, run by the Magnet Theater, at a recent company offsite meeting. One of the basic tenets of improvisational comedy, it turns out, is to start with “yes” — and even more specifically with “yes and.” When you work with someone in a scene, your challenge is to resist disputing, challenging, or negating whatever your fellow actor says, and instead embrace, work with and build on it.

What I realized quickly was how good it felt to say “Yes and,” and how much more smoothly it made the scene move forward. So why does “no” so frequently remain the default response in the workplace?