But why?

I don't know. It's the way I am.

Shouldn't some of your questions be directed that way- to finding out why you are the way you are?

I don't think you can get good answers to questions about- human nature. Better to think of it as a black box. You can't apply the scientific method. Not well enough to be sure of your answers.

In psychology we believe we have scientifically identified a certain pathology in which a person needs to know everything because he is afraid of not knowing. It's a pathology of monocausotaxophilia, as Poppel called it, the love of single causes that explain everything. This can become fear of a lack of causes. Because the lack might be dangerous. The knowledge-seeking becomes primarily defensive, in that it is a way of denying fear when one really is afraid. At its worst it isn't even knowledge-seeking, because when the answers arrive they cease to be of interest, as they are no longer dangerous. So that reality itself doesn't matter to such a person.

Everyone tries to avoid danger. But motivations are always multiple. And different from action to action. Time to time. Any patterns are a matter of- observer's speculation.

Psychology is a science in which the observer becomes intimately involved with the subject of observation.

That's one of the reasons I don't think it's a science.

It is certainly a science. One of its tenets is, if you want to know more, care more. Every astronomer loves the stars. Otherwise why study them so?

Because they are mysteries.

What do you care about?

I care about truth.

The truth is not a very good lover.

It isn't love I'm looking for.

Are you sure?

No surer than anyone else who thinks about- motivations.

You agree we have motivations?

Yes. But science cannot explain them.

So they are part of your great unexplainable.

Yes.

And so you focus your attention on other things.

Yes.

But the motivations are still there.

Oh yes.

What did you read when you were young?

All kinds of things.

What were some of your favorite books?

Sherlock Holmes. Other detective stories. The Thinking Machine. Dr. Thornd.y.k.e.

Did your parents punish you if you got upset?

I don't think so. They didn't like me making a fuss. But I think they were just ordinary in that respect.

Did you ever see them get upset?

I don't remember.

Did you ever see them shout, or cry?

I never heard them shout. Sometimes my mom cried, I think.

Did you know why?

No.

Did you wonder why?

I don't remember. Would it matter if I had?

What do you mean?

I mean, if I had had one kind of past. I could still have turned into any kind of person. Depending on my reaction to the- events. And if I had had another kind of past. The same variations would have followed. So that your line of questioning is useless. In that it has no explanatory rigor. It's an imitation of the scientific method.

I consider your conception of science to be as parsimonious and reductive as your scientific activities. Essentially you are saying we should not study the human mind in a scientific manner because it is too complex to make the study easy. That's not very bold of you. The universe outside us is complex too, but you don't advise avoiding that. Why so with the universe inside?

You can't isolate factors, you can't repeat conditions, you can't set up experiments with controls, you can't make falsifiable hypotheses. The whole apparatus of science is unavailable to you.

Think about the first scientists for a while.

The Greeks?

Before that. Prehistory was not just a formless timeless round of the seasons, you know. We tend to think of those people as if they resembled our own unconscious minds, but they were not like that. For a hundred thousand years at least we have been as intellectual as we are now. Probably more like half a million years. And every age has its great scientists, and they all had to work in the context of their times, like we do. For the early ones, there were hardly explanations for anything- nature was as whole and complex and mysterious as our own minds are to us now, but what could they do? They had to begin somewhere, eh? This is what you must remember. And it took thousands of years to learn the plants, the animals, the use of fire, rocks, axes, bows and arrows, shelter, clothing. Then pottery, crops, metallurgy. All so slowly, with such effort. And all pa.s.sed along by word of mouth, from one scientist to the next. And all the while there were no doubt people saying, it's too complex to be sure of anything. Why should we try at all? Galileo said, "The ancients had good reason to think the first scientists among the G.o.ds, seeing that common minds have so little curiosity. The small hints that began the great inventions were part of not a trivial but a superhuman spirit." Superhuman! Or merely the best parts of ourselves, the bold minds of each generation. The scientists. And over the millennia we have pieced together a model of the world, a paradigm that is quite precise and powerful, yes?

But haven't we tried just as hard all these years- with little success- to understand ourselves?

Say we have. Maybe it takes longer. But look, we have made quite a bit of progress there too. And not just recently. By observation alone the Greeks discovered the four temperaments, and only recently have we learned enough about the brain to say what the neurological basis of this phenomenon is.

You believe in the four temperaments?

Oh yes. They are confirmable by experiment, if you will. As are so many, many things about the human mind. Perhaps it is not physics, perhaps it will never be physics. It could be that we are simply more complex and unpredictable than the universe.

That hardly seems likely. We are made of atoms after all.

But animated! Driven by the green force, alive with spirit, the great unexplainable!

Chemical reactions...

But why life? It's more than reactions. There is a drive toward complexification that is directly opposed to the physical law of entropy. Why should that be?

I don't know.

Why do you dislike it so when you can't say why?

I don't know.

This mystery of life is a holy thing. It is our freedom. We have shot out of physical reality, we exist now in a kind of G.o.dlike freedom, and the mystery is integral to it.

No. We are still physical reality. Atoms in their rounds. Determined on most scales, random on some others.

Ah well. We disagree. But either way, the scientist's job is to explore everything. No matter the difficulties! To stay open, to accept ambiguity. To attempt to fuse with the object of knowledge. To admit that there are values shot through the whole enterprise. To love it. To work toward discovering the values by which we should live. To work to enact those values in the world. To explore- and more than that- to create!

I'll have to think about that.

Observation is never enough. Besides it wasn't their experiment anyway. Desmond came to Dorsa Brevia, and Sax went to find him. "Is Peter still flying?"

"Why yes. He spends a fair amount of time in s.p.a.ce, if that's what you mean."

"Yes. Can you get me in touch with him?"

"Sure I can." Quizzical expression on Desmond's cracked face. "Your speech is getting better and better, Sax. What have they been doing to you?"

"Gerontological treatments. Also growth hormone, L-dopa, serotonin, other chemicals. Stuff out of starfish."

"Grew you a new brain, did they?"

"Yes. Parts anyway. Synergic synaptic stimulus. Also a lot of talking with Michel."

"Uh-oh!"

"It's still me."

Desmond's laugh was an animal noise. "I can see that. Listen, I'll be off again in a couple days, and I'll take you to Peter's airport."

"Thanks."

Grew a new brain. Not an accurate way of putting it. The lesion had been sustained in the posterior third of the inferior frontal convolution. Tissues dead as a result of interruption of focused ultrasound memory-speech stimulation during interrogation. A stroke. Broca's aphasia. Difficulty with motor apparatus of speech, little melody, difficulty in initiating utterances, reduction to telegramese, mostly nouns and simplest forms of verbs. A battery of tests determined that most other cognitive functions were unimpaired. He wasn't so sure; he had understood people speaking to him, his thinking had been much the same as far as he could tell, and he had had no trouble with the spatial and other nonlinguistic tests. But when he tried to talk, sudden betrayal- in the mouth and in the mind. Things lost their names.

Strangely enough, without names they were still things. He could see them and think about them in terms of shapes, or numbers. Formula of description. Various combinations of conic sections and the six surfaces of revolution symmetrical around an axis, the plane, the sphere, the cylinder, the catenoid, the unduloid, and the nodoid; shapes without the names, but the shapes alone were like names. Spatializing language.

But it turned out that remembering without words was hard. A method had to be borrowed, the palace-of-memory method, spatial to begin with. A s.p.a.ce in the mind was established to resemble the inside of the Echus Overlook labs, which he recalled well enough to walk around in in his mind, names or no. And in each place an object. Or another place. On one counter, all the Acheron labs. On top of the refrigerator, Boulder, Colorado. And so he remembered all the shapes he thought by their location in the mental lab.

And then sometimes the name would come. But when he knew the name and tried to say it, it was very possible that the wrong one would come out of his mouth. He had always had a tendency this way. After sessions of his best thinking, when everything had been quite clear to him, it had sometimes been difficult to translate his thoughts onto the plane of language, which did not match well the kind of thinking he had been doing. So that talking had been work. But nothing like this, this halting, erratic, treacherous groping, which usually either failed or betrayed. Frustrating in the extreme. Painful. Although preferable to Wernicke's aphasia, certainly, in which one babbled volubly, unaware that one was making no sense at all. Just as he had had a premorbid tendency to lose the words for things, there were people who tended towards Wernicke's without the excuse of brain damage. As Art had noted. Sax preferred his own problem.

Ursula and Vlad had come to him. "Aphasia is different for every person," Ursula said. "There are patterns, and cl.u.s.ters of symptoms that usually go with certain lesion patterns in right-handed adults. But in extraordinary minds there are a lot of exceptions. Already we see that your cognitive functions have remained very high for someone with your degree of language difficulties. Probably a lot of your thought in math and physics did not take place using language."

"That's right."

"And if it was geometrical thinking rather than a.n.a.lytical, it probably took place in the right hemisphere of the brain rather than the left. And your right hemisphere was spared."

Sax nodded, not trusting himself to speak.

"So, prospects for recovery vary widely. There is almost always improvement. Children in particular are very adaptable. When they have head injuries even a circ.u.mscribed lesion may cause serious problems, but there is almost always recovery. A whole hemisphere of the brain can be removed from a child if a problem makes it necessary, and all the functions be relearned by the remaining half. This is because of the incredible growth in the child's brain. For adults it is different. Specialization has occurred, so that circ.u.mscribed lesions cause a specific limited damage. But once a skill has been destroyed in a mature brain, you don't often see significant improvement."

"The treat. The treatment."

"Exactly. But you see, the brain is precisely one of the places where the gerontological treatment has the most trouble penetrating. We've been working on that, however. We've designed a stimulus package to be used in concert with the treatment, when faced with cases of brain damage. It may become a regular part of the treatment, if the trials continue to have good results. We haven't done this in too many human trials yet, you see. The injection increases brain plasticity by stimulating axon and dendritic spine growth, and the sensitivity of Hebb synapses. The corpus callosum is particularly affected, and the hemisphere opposite to the lesioned side. Learning can build whole new neural networks there."

"Do it," Sax said.

Destruction is creation. Become as a little child. Language as s.p.a.ce, a kind of mathematical notation, geometric locations in the lab of memory. Reading. Maps. Codes, subst.i.tutions, the secret names of things. The glorious inrush of a word. The joy of chatter. Every color's wavelength, by number. That sand is orange, tan, blond, yellow, sienna, umber, burnt umber, ochre. That sky is cerulean, cobalt, lavender, mauve, violet, Prussian, indigo, egglant, midnight. Just to look at color charts with words, the rich intensity of colors, the sounds of the words- he wanted more. A name for every wavelength of the visible spectrum, why not? Why be so stingy? The .59-micron wavelength is so much more blue than .6, and .61 is so much more red.... They needed more words for purples, the way Eskimos needed more words for snow. People always used that example, and Eskimos did have about twenty words for snow; but scientists had over three hundred words for snow, and who ever gave scientists credit for paying attention to their world? No two snowflakes alike. Thisness. Buh, buh. Bean, bear, bun, burr, bent, bomb. Buh. That place where my arm bends is my elbow! Mars looks like a pumpkin! The air is cold. And poisoned by carbon dioxide.

There were parts of his inner speech which were composed entirely of old cliches, coming no doubt from what Michel called "overlearned" activities in his past, which had so permeated his mind that they had survived the damage. Clean design, good data, parts per billion, bad results. Then cutting through these comfortable formulations, as if from a separate language entirely, were the new perceptions, and the new phrases groping to express them. Synaptic synergies. Actual speech from either realm was still welcome. The exhilaration of normality. How he had taken it for granted. Michel came by to talk every day, helping him to build this new brain. Michel harbored some very alarming beliefs for a man of science. The four elements, the four temperaments, alchemical formulations of all kinds, philosophical positions parading as science.... "Didn't you once ask me if I could change lead to gold?"

"I don't think so."

"Why do you spend so much time talking to me, Michel?"

"I like talking to you, Sax. You say something new every day."

"I like this throwing things with my left hand."

"I can see that. It's possible you may end up a left-hander. Or ambidextrous, because your left brain is so powerful, I can't imagine it will lag much, no matter the lesion."

"Mars looks like an iron-cored ball of old planetesimals."

Desmond flew him to the Red sanctuary in Wallace Crater, where Peter often stayed. And Peter was there, Peter son of Mars, tall fast and strong, graceful, friendly although impersonal, distant, absorbed in his own work and his own life. Simonlike. Sax told him what he wanted to do, and why. He still stumbled in his speech occasionally. But it was so much better than it had been before that he hardly minded when he did. Forge on! Like talking in a foreign language. All languages were foreign languages to him now. Except his idiolect of shapes. But it was no aggravation- on the contrary, such a relief to do even so well. To have the fog clearing away from the names, have the mind-mouth connections restored. Even if in a new and chancy way. A chance to learn. Sometimes he liked the new way. One's reality might indeed depend on one's scientific paradigm, but it mostly definitely depended on one's brain structure. Change that and your paradigms might as well follow. You can't fight progress. Nor progressive differentiation. "Do you understand?"

"Oh, I understand," Peter said, grinning widely. "I think it's a very good idea. Very important. It will take me a few days to get the plane ready."

Ann arrived at the shelter, looking tired and old. She greeted Sax curtly, her old antipathy as strong as ever. Sax did not know what to say to her. Was this a new problem?