Pio buzzed. ‘I don’t think you blame me for the gnat; I think you’re still punishing me for my debate with Lila. There might have been a problem for us with the arrows clashing. At the time nobody had proved that there wouldn’t be, and I was right to point that out.’

‘So you’d say we’ve been lucky,’ Agata pressed him, ‘but you’re satisfied now that there’s no reason not to forge ahead, all the way to the reunion?’

‘That’s a weighty demand,’ Pio replied lightly. ‘If you’re asking me whether I’m going to advocate any kind of change in course in the immediate future, the answer is no. There’s nothing we could do at this moment that would make the Peerless any safer, and no risk that we urgently need to avoid.’

He gestured towards the floor – towards the rim, out into the void. ‘But as Lila said in the debate, the orthogonal worlds are still out there, and they can’t annihilate us any more. So don’t ask me to renounce the possibilities they offer. All I’m calling on people to do right now is to keep an open mind. Is that so terrible?’

Agata said, ‘You’ve forgotten your own slogan: “Let the ancestors burn.” Why should anyone open their mind to that?’

‘Let them burn if necessary,’ Pio replied. ‘If the alternative is even worse.’

Agata stopped walking. ‘You know, you almost sound convincing sometimes. But you were ready to give up on the home world before on much weaker grounds than necessity.’

Pio raised his hands contritely. ‘I got carried away in the debate. I know it offended you, and I’m sorry.’

They’d almost reached the turn-off to Lila’s office. Agata didn’t want to detour for a meal now in case Pio insisted on joining her.

‘I have to go,’ she said. ‘You can tell Cira that you tried your best, to no avail.’

‘What are you talking about?’ But Pio’s baffled demeanour was a bit too self-conscious to be believable.

‘You should find something useful to do,’ Agata suggested. ‘I’m sure they still need help re-bedding the medicinal gardens.’

‘And your work’s useful?’ he retorted. ‘Try some gardening yourself!’

‘Goodbye, Pio.’ Agata strode towards the intersection, glancing at her brother with her rear gaze in the hope that he’d set off back down the corridor so she could get to the food hall after all. But he must have been hungry too, because he headed for the hall himself.

Agata muttered imprecations against her family and readied herself for a bell or two of higher mathematics through the eyes of a Starver.

‘Are you eating for four now?’ Medoro joked.

Agata looked up. ‘We can share if you want to. I might have ordered too much.’

Medoro sat on the floor, facing her, and helped himself to a loaf. The food hall was quiet, and Agata had been lost in thought.

‘How’s work?’ he asked.

‘I finished proving an interesting result today,’ she said. ‘Lila and I had been fairly sure that it was true, but it took a while to clear up all the technicalities.’