‘What else can it imply?’

‘They might have been so dissatisfied with the Neighbor Star that they decided to move on elsewhere. Perhaps they stopped long enough to mine some asteroids for new materials they would need for construction and for refurbishing the micro-fusion motors. Then on they would go.’

‘And if that were so, how can we know where they would be?’

‘They've been gone almost fourteen years. With hyper-assistance, they can travel only at the speed of light. If they have reached any star and settled in its neighborhood, it would have to be at a star within fourteen light-years distance of us. There are not very many of those. At superluminal velocity, we can visit each of those. With neuronic detectors, we can quickly decide whether Rotor is in the neighborhood of any of them.’

‘They might be wandering through space between stars at this very moment. How would we detect them then?’

‘We wouldn't, but at least we increase our own chances just a bit if we investigate a dozen stars in six months with our neuronic detector, instead of spending that much time investigating one star in a futile search. And if we fail - and we have to face the fact that we might fail - then at least we will return with considerable data on a dozen different stars, a white dwarf, a blue-white hot star, a Solar look-alike, a close binary, and so on. We're not likely to make more than one trip in our lifetime, so why not make it a good one, and go down in history with a huge bang, eh, Crile?’

Crile said thoughtfully, ‘I suppose you're right, Tessa. To comb a dozen stars and find nothing will be bad enough, but to search a single star vicinity and return thinking that Rotor might have been somewhere else that was reachable but that we lacked the time to explore would be much worse.’

‘Exactly.’

‘I'll try to remember that,’ said Crile sadly.

‘Another thing,’ said Wendel. ‘The neuronic detector might detect intelligence not of Earthly origin. We wouldn't want to miss it.’

Fisher looked startled. ‘But that's not likely, is it?’

‘Not at all likely, but if it happens, all the more reason not to miss it. Especially if it is within fourteen light-years of Earth. Nothing in the Universe can be as interesting as another intelligent life-form - or as dangerous. We'd want to know about it.’

Fisher said, ‘What are the chances of detecting it at all if it is not of Earthly origin? The neuronic detectors are geared for human intelligence only. It seems to me that we wouldn't even recognize a really odd life-form as being alive, let alone as being intelligent.’

Wendel said, ‘We may not be able to recognize life, but we can't possibly fail to recognize intelligence, in my view, and it's not life but intelligence that we're after. Whatever intelligence might be, however strange, however unrecognizable, it has to involve a complex structure, a very complex structure - at least as complex as the human brain. What's more, it's bound to involve the electromagnetic interaction. Gravitational attraction is too weak; the strong and weak nuclear interactions are too short-range. And as for this new hyperfield we're working with in superluminal flight, it doesn't exist in nature as far as any of us knows, but exists only when it is devised by intelligence.

‘The neuronic detector can detect an elaborately complex electromagnetic field that will signify intelligence no matter the form or chemistry into which that intelligence may be molded. And we will be ready to either learn or run. As for unintelligent life, that is not at all likely to be dangerous to a technological civilization such as ourselves - though any form of alien life, even at the virus stage, would be interesting.’

‘And why must all this be kept secret?’

‘Because I suspect - in fact, I know - that the Global Congress will want us back very quickly so that they can be sure the project is successful and so that they can learn to build better models of superluminal vessels based on our experience with this prototype. I, on the other hand, if things go well, would certainly want to see the Universe and let them wait. I don't say I'll definitely do it, but I want the option held open. If they knew I was planning that - even thinking it - I suspect they would try to crew the ship with others whom they would consider more amenable to orders.’

Fisher smiled weakly.

Wendel said, ‘What's wrong, Crile? Suppose there's no sign of Rotor or its people. Would you then just want to go back to Earth in disappointment? The Universe at your fingertips, but given up?’

‘No. I'm just wondering how long will it take to put in the detectors and all the other things you might dream up. In a little over two years, I'll be fifty. At fifty, agents working for the Office are routinely taken off field duty. They get desk jobs on Earth and are no longer allowed to take space-flights.’

‘Well?’

‘In a little over two years, I will no longer qualify for the flight. They'll tell me I'm too old, and the Universe won't be at my fingertips after all.’

‘Nonsense! They're going to let me go and I'm over fifty right now.’

‘You're a special case. It's your ship.’

‘You're a special case, too, since I will insist on you. Besides, they won't find it so easy to get qualified people to go on the Superluminal . It will be all we can do to persuade anyone to volunteer. And they'll have to volunteer; we can't risk placing the trip into the hands of unwilling and frightened draftees.’

‘Why wouldn't they volunteer?’

‘Because they're Earthmen, my good Crile, and to almost all Earthmen, space is a horror. Hyperspace is a greater horror still and they're going to hang back. There is going to be you and me, and we're going to need three more volunteers and I tell you we'll have trouble getting them. I've sounded out many, and I have two good people with a halfway promise: Chao-Li Wu and Henry Jarlow. I haven't got my third yet. And even if, against all likelihood, there are as many as a dozen volunteers, they're not going to cut you out in favor of anyone else, for I will insist on your going with me as my ambassador to the Rotorians - if that becomes necessary. And if even that is not enough, I promise you that the ship will take off before you're fifty.’

And now Fisher smiled with honest relief and said, ‘Tessa, I love you. You know, I really do.’

‘No,’ said Wendel, ‘I don't know that you really do, especially when you say it in that tone of voice, as though the admission has caught you by surprise. It's very odd, Crile, but in the almost eight years we've known each other, and lived together, and made love to each other, you've never once said that.’

‘Haven't I?’

‘Believe me, I've listened. Do you know what else is odd? I've never said that I loved you, and yet, I love you. It didn't start that way. What do you suppose happened?’

Fisher said in a low voice, ‘It may be that we've fallen in love with each other so gradually that we never noticed. That may happen sometimes, don't you think?’

And they smiled at each other shyly, as though wondering what they ought to do about it.