And yet both films share an identical image. In the opening of “Boyhood,” 7-year-old Mason is shown lying in the grass, watching the clouds. Young Lincoln is seen, fleetingly, doing the same thing, although it’s clear that in 1817, taking a moment to dream is a more furtive practice. Still, there they are: The Great Emancipator-to-Be and the nascent hipster, two boys, gazing up at the blue skies of summer.

I had summers like that, too, in the 1960s, and although I became a woman in adulthood and struggled with the gender business until then, it’s nevertheless true that I had a boyhood, and that many moments in it were pretty blissful. I passed my days in the farmland and forests of rural Pennsylvania. I went fishing for brown trout, dived into creeks from covered bridges and shot off model rockets with my father. I climbed onto the top of the backstop at the elementary school playground — abandoned in summer — and learned swear words from a boy named Kevin Walsh.

My wife, Deirdre, told me about her memories of summer girlhoods and, to my surprise, her list is not so unlike mine: slumber parties, hot dogs, playing sharks and minnows in a pool. About the most culturally feminine thing she did before she turned 10 was read about Bobby Sherman in Tiger Beat magazine.

I’m not sure I would have traded my boyhood for a girlhood, if given the chance. I know I would have been grateful to have been spared the misery of adolescence, of course, and the wearisome transition that came after, but on the whole I give thanks for those July days I spent staring up at the blue sky. That boy lives inside me, even now. His dreams are still mine.

“The Better Angels” opens with a shot of the Lincoln Memorial in the snow, then cuts to Indiana 1817. As the film proceeds, we wonder how the child we are observing connects to the president he became. Even in the midst of war, did he not carry within him, somewhere, that child, staring up at the blue skies of Indiana?