The science writing in “The Strangest Man” isn’t glib, but neither does it require problem-solving on the part of the reader. In most cases, Farmelo presents the technical matter clearly and efficiently, and in all cases — one of the great joys of the book — Dirac’s scientific insights are placed within the circumstances in which they were born: e.g., the “sweltering July” of 1926 when Dirac, sitting at his college desk, produced his paper on what became Fermi-Dirac statistics.

In a prologue, Farmelo describes a visit to the elderly Dirac paid by his biologist colleague Kurt Hofer. Through the eyes of Hofer, we see Dirac suddenly break out of monosyllables to talk for two hours with increasing vehemence about his monstrous father. This represents the author’s careful decision to keep the tale Dirac told about his childhood separate from — even as it overshadows — the rest of the book, and it ends with Hofer’s thoughts, not Dirac’s: “ ‘I simply could not conceive of any childhood as dreadful as Dirac’s.’ . . . Could it be that Dirac — usually as literal-minded as a computer — was exaggerating? Hofer could not help asking himself, over and again: ‘Why was Paul so bitter, so obsessed with his father?’ ”

The conflict between this prologue (which gives ample reason for Dirac to be bitter about his father) and the seemingly warm family life that emerges in the first chapter casts a tension over the rest of the book very similar to that felt when reading a mystery. And as in a mystery, the penultimate chapter sheds new light. There Farmelo delves into a sensitive exploration of the possibility that Dirac was autistic, and of the ways in which his lack of facility in reading the emotions of others affected their perceptions of him and his perceptions of them. The emphasis on Dirac’s childhood as a story — one Farmelo (along with me) believes to be true — usefully reinforces the importance of point of view.

In a memorable episode, Dirac and his wife visit their closest friends, Peter and Anna Kapitza, in Russia. In 1934, the long arm of the Soviet state had wrenched Kapitza, despite his devoted long-distance fellow-traveling, away from his lab at Cambridge under Ernest Rutherford and back into the Soviet Union. In 1937 the friends reunited at the Kapitzas’ summer house in the piney woods of Bolshevo, “with wild strawberries ripe for gathering and a fast-flowing river close by.” They arrived only “days before Stalin authorized the torture of suspected enemies of the people,” Farmelo writes. “On the roads around Bolshevo, some of the trucks marked ‘Meat’ and ‘Vegetables’ hid prisoners on their way to be shot and buried in the forests to the north of the city which Dirac admired through his binoculars.”

Farmelo handles such scenes with a refreshing, cleareyed understanding of how complicated the world actually is. Dirac did not — probably could not — know what the Soviet Union really was; he also could not know who his father really was, and his father could not really know him. These complexities and unresolvably cubist perspectives make, paradoxically, for the most satisfying and memorable biography I have read in years.