How Important Is It To Avoid Negative People?

This morning, Fast Company featured a piece on 7 habits of happy people at work. Avoiding negative people was one of the suggested habits. 

Many I know would argue about the impracticality of this. We cannot usually choose who we work with and for. 

What is practical is how much available time we spend with more positive people and how much time we spend with anyone talking more about what's positive than negative. What's possible is that we don't have to react to negativity with passive endurance or support for negative perspectives and questions. We can instead respond with our own contrasting and intentional focus on what we want, like, value, appreciate, have and are committed to doing and creating. We can be the emotional tone we want to see.