The Maximilian that Charlotte had referred to was a distant cousin on their mother’s side, a German from Hanover, who had overpowered a twenty-two-year-old Martha with the ardour of his certainty. He had taken her to the Black Forest to walk; he had taken her to see castles in Bavaria; he had taken her to see transsexual cabarets in Berlin, where the performers made a show of degradation, as though defeat and loss of empire, two million Germans dead and bankruptcy were not enough; and he had ended up by taking her to his hotel bedroom where he had insisted that he could see no similarity at all between her and her sister. Dizzied and drunk on his attention, Martha had managed to keep only a small degree of detachment when she looked up into his dark eyes and heard his words of Prussian endearment. After short spells together over a period of almost two years, Maximilian married a French woman and went to work for a bank in Paris.

Hurt though she had been, Martha found that after a year or so she could smile at the thought of Maximilian’s excesses. Eventually she persuaded herself that she had seen him as a curio, an interlude with shuddering excitements, and not much more. She had certainly not believed that he was the other half of her soul. He was too much of a show-off, for one thing; and for another, she had never felt that half her soul was missing.

When she saw the various griefs of her patients, she was pleased not to have carried this feeling of incompleteness in her own life. The search for what was absent made them vulnerable. Perhaps this was one way in which she differed from Charlotte, who was more restless: a minute variation not in gene or upbringing but in an old-fashioned thing called ‘temperament’. Or ‘pure chance,’ as her father might have said.

Martha felt lust for men, their hands and voices and crushing physical certainty, and had experienced what she had seen somewhere described as the ‘boundless joys of shame’ – with the army officer as well as with Maximilian (though not with the Hungarian, for reasons she now regretted and didn’t want to confess to Charlotte). She had read widely to understand the physical background of the romantic pain that she was sometimes presented with in her consulting rooms; she knew of everything that women and men did with one another, even if some of it made her shudder or laugh. She sometimes regretted that she had never, so far as she knew, been the object of a fixated desire in the way that Delphine had been to Anton; but not when she saw where the passion had left him.

She believed she had in fact been too much loved when young. She had had an alter ego in her twin; she needed no other. Her uncle, Jacques, had provided her with a youthful object of admiration and love, and perhaps some smoothly sublimated desire. She had been able to find a release for latent maternal feeling early on in the shape of Daniel, her cousin. She had had the playful adoration of her father and the humorous support of her mother.