"At present there is probably no family in the Nucleus that doesn't have at least one Id sargh. Many of us have one for every member of the family." Marthasa paused. The tone of his voice changed. "When you've had one almost all your life as I've had Sal Karone it—well, it does something to you."
"What do you mean?" Cameron asked cautiously.
"Consider the situation from Sal Karone's point of view. He has no life whatever that is his own. His whole purpose is to give me companionship and satisfy my requirements. And I don't have to force him in any way. It's all voluntary. He's free to leave, even, any time he wants to. But I'm certain he never will."
"Why do you feel so sure of this?"
"It's hard to explain. I feel as if I've become so much a part of him that he couldn't survive alone any more. He's the one who's made it that way, not me. I have become indispensable to his existence. That's the way I explain it to myself. Most of my friends agree that this is about right."
"It's rather difficult to understand a relationship like that—unless you put it in terms I am familiar with on Earth."
"Yes—? What would it be called among your people?"
"When a man so devotes his life to another we say it is because of love."
Marthasa considered the word. "You would be wrong," he said. "It is just that in some way we have become indispensable to the Ids. They're parasites, if you want to put it that way. But they provide us a relationship we can get nowhere else, and that does us a great deal of good. That's what I meant when I said it does something to us."
"What about the Id's own culture? Haven't they any community ties among themselves, or do they ignore their own kind?"