Several years ago, Stephen Colbert gave the commencement speech at my alma mater, Knox College. He talked about the importance of approaching life as improv. He explained that when actors improvise, the scene unfolds as each individual says, Yes, and. You have to listen to what’s been presented, agree, and add to the story. He proclaimed that saying yes and is what leads us to knowledge and opportunity.

Colbert is right. I’ve become a better writer and also more productive by trying new things. Writing a new poem, testing out nonfiction and fiction, keeping my hand in scholarly research, agreeing to write a blog post for a literary journal—these activities and the challenges they present make me feel creative, alive.

The adrenaline kicks in when I step into my classroom. I try new assignments and use new books every semester. I feel a responsibility to colleagues, too, so I tend to help out when I’m asked to serve on a search committee. I even instigate collaboration with other writers and teachers. I like the improv way of life, the what if of a lush, verdant life.

Recently, a friend and colleague at another university asked if she could list me as possible on-site reviewer for the writing program in which she teaches. Feeling strapped for time and fighting a respiratory infection, I asked for more information. She responded that it’d be a lot of work and that she had other names. I declined. Her response: “I always want to cheer when a colleague says no to something, even if I asked them. Because sometimes we have to say no!”

A couple of weeks later, I heard from a writer with whom I was supposed to collaborate. Our schedules hadn’t synced up over the summer, and we’d agreed to tackle an essay together in October. She wrote that she needed “to flake out” on me. Her writing and publishing were going really well, and she had to cut back on the number of projects she’d planned. She wasn’t flaking out at all. She was being realistic. She was prioritizing.

I understood; I was feeling similar pressure. Honestly, I was relieved by these two exchanges.

It’s amazing to me how difficult saying no has become. Maybe the request—will you do this?—sounds like a compliment: I think you’re good at this sort of thing. Maybe we fear that declining one task will send the message that we aren’t open to future opportunities. Maybe we lose track of how much we’ve agreed to do and how much time even the small tasks take when they add up. Maybe we tell ourselves that we work best under pressure and are master multi-taskers.

If we never say no, however, we become less able to prioritize and are increasingly likely to put our obligations into conflict with each other.

I’ll make time is a lie we tell ourselves. Time cannot be created. There are two common ways of perceiving time: either we are rushing headlong into the future, or the future is rushing headlong toward us. Either way, there will exist only 24 hours in each day.

Choosing not to do something can empower us, can remind us that we have choices.

Saying no to one thing can allow us to say yes to something more important, even if we don’t see that bigger, better thing coming yet.

Say no because every time you say yes to something that isn’t writing, that’s time that could be spent writing. I once heard novelist Aimee Bender say, “There is no novel in your mind. The only book that exists is the one on the page.” Writing a book requires time spent in the act of writing that book. Saying no to other things gives the book a chance to exist.

Maybe we can carve out time, but if so, we must slice into time with the scythe that is no. A writer must keep the blade sharp and her wielding arm strong. She must be willing to shape time with no, one of many tools in the writer’s toolbox.

Beyond imagining the power of this metaphorical scythe, I’m not exactly sure how to wield no. I can’t quite yet make out the shape in the overgrowth. I know that I want to write books and that, while we can’t control everything in our lives, my choices make writing books more—or less—possible.

Anna Leahy blogs at Lofty Ambitions: http://loftyambitions.wordpress.com. Her book Constituents of Matter won the Wick Poetry Prize. She teaches in the MFA and BFA programs at Chapman University, where she directs the Tabula Poetica reading series and edits TAB: The Journal of Poetry & Poetics.