“Have I told you my theory of dynamic range?” Brian asked. No, he hadn’t. So he grabbed some paper and a pen, and as he drew a sine wave, he explained his philosophy. In music, dynamic range is the ratio between the quietest and loudest volumes. The concept, he said, isn’t limited to sound.

“So you know the first time you fall in love,” he continued, “and you feel all of these things you’ve never felt before?”

I nodded.

“Well, that expands your dynamic range, and now you’re way up here” — he pointed to the peak of a wave — “but then you break up and it just feels awful and you think you’ll never love again. But you do, and maybe it’s even better than that first time. So your dynamic range grows again, but it grows in both directions so you have more risk. More to lose, but more to love. It works for all kinds of things in life, and that’s why being a father brings me more energy than I had before.”