Final ripped out a concluding phrase that all but put the 'caster out of commission.

Porus waited for the storm to pass and then said calmly, 'But do you know how I solved it?'

The other's answer was an indistinct mumble.

The Rigellian began speaking rapidly. All traces of amusement had left his face and, after a few sentences, all traces of anger left Final's.

The Arcturian's expression became one of wide-eyed interest. 'No?' he gasped.

'Yes!'

When Porus had finished, Final raced madly to put in rush calls to the printers to delay publication of the coming issue of the J.G.P. for two weeks.

Furo Santins, head of the math department of the University of Arcturus, gazed long and steadily at his Sirian colleague.

'No, no, you're wrong! His equations were legitimate. I checked them rnyself.'

'Mathematically, yes,' retorted the round-faced Sirian. 'But psychologically they had no meaning.'

Santins slapped his high forehead. 'Meaning! Listen to the mathematician talk. Great space, man, what have mathematics to do with meaning? Mathematics is a tool and as long as it can be manipulated to give proper answers and to make correct predictions, actual meaning has no significance. I'll say this for Tan Porus - most psychologists don't know enough mathematics to handle a slide-rule efficiently, but he knows his stuff.'

The other nodded doubtfully, 'I guess so. I guess so. But using imaginary quantities in psychological equations stretches my faith in science just a little bit. Square root of minus one!'

He shuddered…

The seniors' lounge in Psychology Hall was crowded and a-buzz with activity. The rumor of Porus's solution to the now-classic problem of the squid had spread fast, and conversation touched on nothing else.

At the center of the thickest group was Lor Haridin. He was young, with but newly acquired Senior status. But as Porus's assistant he was, under present conditions, master of the situation.

'Look, fellows - just exactly what it's all about I don't know. That's the old man's secret. All I can tell you is that I've got the general idea as to how he solved it.'

The others squeezed closer. 'I hear he had to make up a new mathematical notation for the squid,' said one, 'like that time we had trouble with the humanoids of Sol.'

Lor Haridin shook his head. 'Worse! What made him think of it, I can't imagine. It was either a brainstorm or a nightmare, but anyway he introduced imaginary quantities - the square root of minus one.'

There was an awful silence and then someone said, 'I don't believe it!'

'Fact!' was the complacent reply.

'But it doesn't make sense. What can the square root of minus one represent, psychologically speaking? Why, that would mean' - he was doing rapid calculation in his head, as were most of the others - 'that the neural synapses were hooked up in neither more nor less than four dimensions!'

'Sure,' broke in another. 'I suppose that if you stimulate the squid today, it will react yesterday. That's what an imaginary would mean. Comet gas! That's what I say.'

'That's why you're not the man Tan Porus is,' said Haridin. 'Do you suppose he cares how many imaginaries there are in the intermediate steps if they all square out into minus one in the final solution. All he's interested in is that they give him the proper sign in the answer - an answer which will explain that sleep business. As for its physical significance, what matter? Mathematics is only a tool, anyway.'

The others considered silently and marveled.

Tan Porus sat in his stateroom aboard the newest and most luxurious interstellar liner and gazed at the young man before him happily. He was in amazing good humour and, for perhaps the first time in his life, did not mind being interviewed by the keen, efficient employees of the Ether Press.

The Ethereporter on his side wondered in silence at the affability of the scientist. From bitter experience, he had found out that scientists, as a whole, detested reporters - and that psychologists, in particular, thought it fun to practice a bit of applied psych on them and to induce killingly amusing - to others - reactions.

He remembered the time that the old fellow from Canopus had convinced him that arboreal life was the greatest good. It had taken twenty men to drag him down from the tree-tops and an expert psychologist to bring him back to normal.

But here was the greatest of them all, Tan Porus, actually answering questions like a normal human being.

'What I would like to know now, Professor,' said the reporter, 'is just what this imaginary quantity is all about. That is,' he interposed hastily, 'not the mathematics of it - we'll take your word on that - but just a general idea that the ordinary humanoid can picture. For instance, I've heard that the squid has a four-dimensional mind.'

Porus groaned, 'Oh, Rigel! Four-dimensional poppycock! To tell the honest truth, that imaginary I used - which seems to have caught the popular fancy - probably indicates nothing more than some abnormality in the squid's nervous system, but just what, I don't know. Certainly, to the gross methods of ecology and micro-physiology, nothing unusual has been found. No doubt, the answer would lie in the atomic physics of the creature's brain, but there I have no hope.' There was a trace of disdain in his voice. 'The atomic physicists are too far behind the psychologists to expect them to catch up at this late date.'

The reporter bore down furiously on his stylus. The next day's headline was clear in his mind: Noted Psychologist Blasts Atomic Physicists!

Also, the headline of the day after: Indignant Physicists Denounce Noted Psychologist!

Scientific feuds were great stuff for the Ether Press, particularly that between psychologists and physicists, who, it was well known, hated each other's guts.

The reporter glanced up brightly. 'Say, Professor, the human-oids of the galaxy are very interested, you know, in the private lives of you scientists. I hope you don't mind if I ask you a few questions about your trip home to Rigel IV.'

'Go ahead,' said Porus, genially. Tell them it's the first time I'm getting home in two years. I'm sort of looking forward to it. Arcturus is just a bit too yellow for my eyes and the furniture you have here is too big.'

'It's true, isn't it, that you have a wife at home?'

Porus coughed. 'Hmm, yes. Sweetest little woman in the galaxy. I'm looking forward to seeing her, too. Put that down.'

The reporter put it down. 'How is it you didn't bring her to Arcturus with you?'

Some of the geniality left the Rigellian's face. 'I like to be alone when I work. Women are all right - in their place. Besides, my idea of a vacation is one by myself. Don't put that down."

The reporter didn't put it down. He gazed at the other's little form with open admiration. 'Say, Prof, how did you ever get her to stay home, though? I wish you'd tell me the secret.' Then, with a wealth of feeling he added, 'I could use it!'

Porus laughed. 'I tell you, son. When you're an ace psychologist, you're master in your own home!'

He motioned the interview to an end and then suddenly grasped the other by the arm. His green eyes were piercingly sharp. 'And listen, son, that last remark doesn't go into the story, you know.'

The reporter paled and backed away. 'No, sir; no, sir! We've got a little saying in our profession that goes: "Never monkey around with a psychologist, or he'll make a monkey of you."'

'Good! I can do it literally, you know, if I have to.'

The young press employee ducked out hastily after that, wiped the cold perspiration from his brow and left with his story. For a moment, towards the last, he had felt himself hanging on the ragged edge. He made a mental note to refuse all future interviews with psychologists - unless they raised his pay.