“Closing Time,” a popular song from the late 1990s, ends with the lyric, “Every new beginning comes from some other beginning’s end.” That line has been on my mind this week, as my son approached his last day of kindergarten. The last day of the first year. The end of one beginning. The launch of something new. 

“Life is one big transition,” said Baseball Hall of Fame member Willie Stargell. Change is complicated, though, precisely because of the idea noted in the song lyric—when something new is beginning, that means something else has ended. Navigating times of transition with positivity asks us to hold multiple—even opposing—feelings at the same time, and to find peace and pleasure in life’s next steps.

This ability to experience two emotions simultaneously is often cited by psychologists as a sign of maturity. Jeff Larsen, a social psychology professor at the University of Tennessee, has done research on people’s emotional reactions to films. He found that 44 percent of people leaving the film “Life Is Beautiful,” which features a father and son bonding and even finding joy in a Nazi concentration camp, reported feeling “both happy and sad” after the screening. After watching the Disney film “The Little Mermaid,” which ends with the heroine marrying her true love but having to leave her father, most 11-year-old girls reported mixed emotions. Six-year-olds like my son, however, only could identify a single emotion.

So on the last day of school, my bigger, taller, stronger, funnier, more confident, soon-to-be-first-grader will not be an expert in emotional ambivalence. But I will be reveling in mine. I miss my little guy at the same time that I am proud of how much he is growing and learning. I am nervous about adjusting to new routines, but excited for the friends and teachers who will walk into the future with us. I will shed a tear for the end of one chapter, but fix my eyes on the beginning of the next. The possibilities are literally endless.