But such an event was as scarce as a double eclipse; Thorby's mother's hope lay in heart failure, stroke, or other hazard of old age.

Thorby as adopted youngest son of Captain Krausa, senior male of the Krausa sept, titular head of Sisu clan (the Captain's mother being the real head), was senior to three-fourths of his new relatives in clan status (he had not yet acquired ship's rank). But seniority did not make life easier. With rank goeth privileges -- so it ever shall be. But also with it go responsibility and obligation, always more onerous than privileges are pleasant.

It was easier to learn to be a beggar.

He was swept up in his new problems and did not see Doctor Margaret Mader for days. He was hurrying down the trunk corridor of fourth deck -- he was always hurrying now -- when he ran into her.

He stopped. "Hello, Margaret."

"Hello, Trader. I thought for a moment that you were no longer speaking to fraki."

"Aw, Margaret!"

She smiled. "I was joking. Congratulations, Thorby. I'm happy for you -- it's the best solution under the circumstances."

"Thanks. I guess so."

She shifted to System English and said with motherly concern, "You seem doubtful, Thorby. Aren't things going well?"

"Oh, things are all right" He suddenly blurted the truth. "Margaret, I'm never going to understand these people!"

She said gently, "I've felt the same way at the beginning of every field study and this one has been the most puzzling. What is bothering you?"

"Uh... I don't know. I never know. Well, take Fritz -- he's my elder brother. He's helped me a lot -- then I miss something that he expects me to understand and he blasts my ears off. Once he hit me. I hit back and I thought he was going to explode."

"Peck rights," said Margaret.

"What?"

"Never mind. It isn't scientifically parallel; humans aren't chickens. What happened?"

"Well, just as quickly he went absolutely cold, told me he would forget it, wipe it out, because of my ignorance."

"Noblesse oblige."

"Huh?"

"Sorry. My mind is a junk yard. And did he?"

"Completely. He was sweet as sugar. I don't know why he got sore... and I don't know why he quit being sore when I hit him." He spread his hands. "It's not natural."

"No, it isn't. But few things are. Mmm... Thorby, I might be able to help. It's possible that I know how Fritz works better than he knows. Because I'm not one of the 'People.'"

"I don't understand."

"I do, I think. It's my job to. Fritz was born into the People; most of what he knows -- and he is a very sophisticated young man -- is subconscious. He can't explain it because he doesn't know he knows it; he simply functions. But what I have learned these past two years I have learned consciously. Perhaps I can advise you when you are shy about asking one of them. You can speak freely with me; I have no status."

"Gee, Margaret, would you?"

"Whenever you have time. I haven't forgotten that you promised to discuss Jubbul with me, either. But don't let me hold you; you seemed in a hurry."

"I wasn't, not really." He grinned sheepishly. "When I hurry I don't have to speak to as many people... and I usually don't know how."

"Ah, yes. Thorby, I have photographs, names, family classification, ship's job, on everyone. Would it help?"

"Huh? I should say so! Fritz thinks it's enough just to point somebody out once and say who he is."

"Then come to my room. It's all right; I have a dispensation to interview anyone there. The door opens into a public corridor; you don't cross purdah line."

Arranged by case cards with photographs, the data Thorby had had trouble learning piecemeal he soaked up in half an hour -- thanks to Baslim's training and Doctor Mader's orderliness. In addition, she had prepared a family tree for the Sisu; it was the first he had seen; his relatives did not need diagrams, they simply knew.

She showed him his own place. "The plus mark means that while you are in the direct sept, you were not born there. Here are a couple more, transferred from collateral branches to sept... to put them into line of command I suspect. You people call yourselves a 'family' but the grouping is a phratry."

"A what?"

"A related group without a common ancestor which practices exogamy -- that means marrying outside the group. "The exogamy taboo holds, modified by rule of moiety. You know how the two moieties work?"

"They take turns having the day's duty."

"Yes, but do you know why the starboard watch has more bachelors and the port watch more single women?"

"Uh, I don't think so."

"Females adopted from other ships are in port moiety; native bachelors are starboard. Every girl in your side must be exchanged... unless she can find a husband among a very few eligible men. You should have been adopted on this side, but that would have required a different foster father. See the names with a blue circle-and-cross? One of those girls is your future wife... unless you find a bride on another ship."

Thorby felt dismayed at the thought. "Do I have to?"

"If you gain ship's rank to match your family rank, you'll have to carry a club to beat them off."

It fretted him. Swamped with family, he felt more need for a third leg than he did for a wife.

"Most societies," she went on, "practice both exogamy and endogamy -- a man must marry outside his family but inside his nation, race, religion, or some large group, and you Free Traders are no exception; you must cross to another moiety but you can't marry fraki. But your rules produce an unusual setup; each ship is a patrilocal matriarchy."

"A what?"

" 'Patrilocal' means that wives join their husbands' families; a matriarchy... well, who bosses this ship?"

"Why, the Captain."

"He does?"

"Well, Father listens to Grandmother, but she is getting old and --"

"No 'buts.' The Chief Officer is boss. It surprised me; I thought it must be just this ship. But it extends all through the People. Men do the trading, conn the ship and mind its power plant -- but a woman always is boss. It makes sense within its framework; it makes your marriage customs tolerable."

Thorby wished she would not keep referring to marriage.

"You haven't seen ships trade daughters. Girls leaving weep and wail and almost have to be dragged... but girls arriving have dried their eyes and are ready to smile and flirt, eyes open for husbands. If a girl catches the right man and pushes him, someday she can be sovereign of an Independent state. Until she leaves her native ship, she isn't anybody -- which is why her tears dry quickly. But if men were boss, girl-swapping would be slavery; as it is, it's a girl's big chance."

Doctor Mader turned away from the chart. "Human customs that help people live together are almost never planned. But they are useful, or they don't survive. Thorby, you have been fretted about how to behave toward your relatives."

"I certainly have!"

"What's the most important thing to a Trader?"

Thorby thought. "Why, the Family. Everything depends on who you are in the Family."

"Not at all. His ship."

"Well, when you say 'ship' you mean 'family.' "

"Just backwards. If a Trader becomes dissatisfied, where can he go? Space won't have him without a ship around him; nor can he imagine living on a planet among fraki, the idea is disgusting. His ship is his life, the air he breathes comes from his ship; somehow he must learn to live in it. But the pressure of personalities is almost unbearable and there is no way to get away from each other. Pressure could build up until somebody gets killed... or until the ship itself is destroyed. But humans devise ways to adjust to any conditions. You people lubricate with rituals, formalism, set patterns of speech, obligatory actions and responses. When things grow difficult you hide behind a pattern. That's why Fritz didn't stay angry."