I met Stephen Hawking in the summer of 1990, when I spent five days in northern Sweden at a conference attended by 30 or so leading cosmologists. He was already almost totally paralyzed; he could move only one finger, with which he controlled a computer and speech synthesizer on his motorized wheelchair.

The new Hawking film shows that this brilliant scientist, whose imagination has plumbed the farthest reaches of reality, is as stumped as the rest of us by mysteries of the heart.

One day, when everyone trooped outdoors for a cocktail party, Hawking's brassy, red-haired nurse, Elaine Mason, asked me to carry him through a field too rough for the wheelchair.

When I scooped him up, he was surprisingly light. He was eyeing me, and I him, when he gagged, his body convulsing. I feared he was going to die during this seizure and several subsequent ones at the conference. I'm amazed that Hawking is alive today.

During another cocktail party, Mason tearfully whispered in Hawking's ear as the rest of us tried to ignore them. Shortly after the conference, Hawking separated from his wife and moved in with Mason, whom he married in 1995. [*See Further Reading below.]

So it was with great curiosity that this week I saw an advance screening of "The Theory of Everything," the new film about Hawking. Based on a memoir by Hawking's ex-wife, Jane Wilde, the film opens as the two graduate students at Oxford meet and fall in love, just as Hawking starts showing symptoms of amyotrophic lateral sclerosis.

The film traces two parallel narratives. In one, Hawking's body falls apart and so, eventually, does his marriage, for reasons that are partly philosophical—Hawking is an atheist, his wife a Christian—but mostly emotional. Wilde is overwhelmed by the physical demands of taking care of her husband and three (yes, three) children, and Hawking, at least initially, is not terribly sympathetic to her plight. They drift apart. She ends up with her church's choirmaster and he with Mason.

The other narrative traces Hawking's scientific career, as he explores the nature of time and space—and dreams of a single equation that will explain everything.

This scientific narrative made Dennis Overbye of The New York Times, who has written extensively about Hawking's work, gnash his teeth. In a terrific review, Overbye details how the film glosses over Hawking's theories and bungles some historical details. For example, Hawking and others are shown discussing "black holes" in the early 1960s, before the term was coined.

I understand Overbye's irritation, but I loved the film. The acting, as Overbye acknowledges, is magnificent. Actor Eddie Redmayne captures Hawking's uncanny ability to be charismatic—and wickedly funny—even though he can barely move a muscle. I never thought, Wow, this actor is doing a great job imitating Hawking. I thought, This is Hawking.

I was even more impressed by how powerfully, and poetically, the film dramatizes two themes. One is that Hawking, although cruelly imprisoned in his body, nonetheless enjoys a rare degree of freedom, because his supercharged imagination can carry him backward and forward in time and into other dimensions and universes. This courageous man exemplifies the mind's power to transcend physical limits.

Hawking once toyed with the idea that if the universe stops expanding and contracts, time might run backward. The film ends movingly with Hawking imagining his life running in reverse, going back to the time when he was healthy and he and Jane had just fallen in love.

The film also evokes a profound paradox posed by modern science. Scientists have been astonishingly successful at mapping out and explaining reality, from the farthest reaches of space to the deepest recesses of matter. These successes have emboldened theorists such as Hawking to envision a "theory of everything" that solves the riddle of reality once and for all.

But this brilliant scientist is baffled—just like the rest of us--by matters of the heart, and so is science as a whole. Yes, science has solved many mysteries, but it remains largely clueless when it comes to the greatest mystery of all, humanity itself.

*Further Reading: I describe the cosmology conference in Sweden and comment on Hawking's theories in this 2010 column and in my 1996 book The End of Science.