I don't want to get to the end of my life and find that I lived just the length of it. I want to have lived the width of it as well.

Length is how many years you get, and width is how much of life you actually take in. Ackerman separates the two to point out that a person can reach old age having simply gone through the motions: work, routine, obligations, years ticking by. Width means depth of experience: attention, curiosity, friendship, wonder, risk. A long life isn't automatically a full one.

The idea fits Ackerman's own outlook as a poet and naturalist, whose writing celebrates the senses and the astonishing detail of the natural world. It also echoes older traditions, from the carpe diem of the Roman poets to Thoreau's belief in living deliberately, and the existentialist view that we are responsible for giving our days meaning rather than just accumulating them.

In practice, it might look like someone who has spent years on autopilot choosing one evening a week to do something unfamiliar, such as joining a pottery class, cooking a dish from another culture with a neighbor, or taking a walk with no phone and really noticing the light, the sounds and the people. None of these adds years, but each widens the life you are already living.