Initially, I walked the galleries looking for the people I was familiar with—the ones whose stories I knew, the ones I wondered about, the ones I would have loved to have met. And then I moved wider, using the Gallery as a way of learning about people. Wondering, as I walked and as I stared, about the faces I passed: how they fit into the history of the country, why each person was there, and not someone else in their place. The faces became a dialogue, the paintings became a conversation.

The National Portrait Gallery is the nation’s family album, I realized. It gives us context. It is our way of describing ourselves and our past to ourselves, our way of interrogating and explaining and exploring who we are, inspecting our roots in a way that is more than just looking at the places from which we come. There is landscape, and there is portrait, after all, and they are ways of explaining the orientation of a sheet of paper, and they are the ways we understand who we are: the places we came from, the people we were.

For years I had loved Constable’s landscapes: the clouds, which seemed so much more cloudlike than any clouds I had ever seen, and which forced me to stare at clouds and wonder if they were art, and the trees, and the way the sense of place gave continuity: the Suffolk landscape, which could have been my own Sussex lanes and skies. Now, for the first time, I saw John Constable: I did not expect him to be handsome, or so pensive. And there was something odd about his eyes: they seemed to be focused on different places. I wondered if he had a lazy eye, as my daughter did when she was young, or if it was simply the way that Ramsay Reinagle had presented him to us. I imagined what it must have been like to live inside that head, to see the world, and its clouds and skies and trees, through John Constable’s strange eyes.

Some portraits were important because of who the subjects were. Others were important because of the artist. Still others were important because of the historical moment, because they were a record of their times, which are our times. Most images gain their power from the moment of intersection: painter and subject, time and history and context, ever-changing context. All come together as we walk the corridors of the National Portrait Gallery.

We look at a portrait and we begin to judge, because human beings are creatures of judgment. We judge the person being painted (a bad king? a good woman?) in the same way that we judge the artist, and occasionally we find ourselves judging them both, particularly when the subject is also the painter: Dame Laura Knight’s self-portrait, a symphony in crimson and vermilion, shows the painter in perfect profile, flanked by the naked flanks of both a model and of the painting of the model. As a woman she was forbidden to attend life-drawing classes, and here she tells us that she is a woman, and she is a master at drawing from life. The technique is remarkable, the statement powerful.