‘And there was no escape. I remember one lad, Ernst, who was brought in with us. His only sin was that his father had been condemned as an enemy of the state for being lazy. Ernst thought he could outsmart them. He tried to win their trust by working as hard as he could. He was always sweeping the floors, cleaning the toilets, making himself useful. One day, he managed to get out of the main building into the courtyard and he made a run for it.’ Holtz shuddered at the memory.

‘They caught him, of course. We were in the dining hall, eating the slops they served us for dinner, when they dragged him in by the hair. Then they stripped him naked. Four nurses held him down on a table while two of the doctors beat the soles of his feet with canes, counting out loud all the time. Ernst was screaming like a scalded baby. They kept beating him till his feet were lumps of raw meat, the flesh hanging off the bones and the blood dripping off the table on to the floor. Eventually, he passed out. And the institute director was standing there with a clipboard, noting how many strokes of the canes and how long it had taken to get to that point. Then he turned to us and said, as calmly as if he was announcing what was for dessert, that we should all remember what would happen to any part of our bodies that didn’t behave as it should.’ Holtz passed a hand over his face, wiping a thin sheen of sweat from his forehead. ‘Do you know, that sadistic bastard remained a member of the German Society of Psychiatrists till he died in 1974? Nobody wants to admit what was done to us.

‘The guilt’s too much, you see. It was hard enough for Germany to accept what we did to the Jews. But what was done to us was worse. Because our good German parents let it happen. They let the state take us away, mostly without any protest. They just accepted what they were told, that we needed to be disposed of for the greater good. And afterwards, nobody wanted to hear our voices.

‘To tell you the truth, I’ve made myself forget a lot of what happened back there. That’s how I’ve coped. The scars are still there though, deep down.’

There was a long silence. Finally, the young skipper drained his beer and said, ‘Why are you telling me this?’