“Bera tried to tell me thirteen centuries ago that I’d get myself into serious trouble someday because I couldn’t tell love from lust. I went back to that memory last night. I wasn’t mature enough then to understand what she was trying to tell me. I hope I am now.”

Derik says that, in Homecoming. But what did he mean? What is the distinction between love and lust?

You might say that they are the extreme ends of human sexual relationships. At one end, love, is a relationship based on mutual caring. At the other end, lust, the relationship is basically one of power, of using another person. It seems to me that where a relationship is along this continuum is far more important than the parties involved.

Often the two are so intermixed that it is difficult to tell them apart. A bit of lust, in the form of sex drive, is probably at the heart of many human relationships. At the extreme, of course, lust is involved in rape and seduction, and the power aspect is perhaps clearest in the use of rape as a weapon of war.

It’s harder to find an example of pure love, but basically both people should feel they are getting at least as much out of the relationship as they are putting into it, and each feels happier together than they would apart. It’s probably not possible in a pure sense, as we can never know what the other person’s true feelings are.

So why does Derik, who is basically a pretty decent sort, have a problem telling love from lust?

Derik is practically sterile, and the women of his own class want nothing to do with him. All his long life, he has taken human slaves as long-term lovers. These slaves are cosseted and cared for throughout their lives.  Derik is a mind reader, but he has always felt it was immoral to read the minds of non-telepaths. The day before the statement above, he accidentally read the mind of a young slave he was trying to seduce—and who seemed quite willing to seduce him in turn—and found out what the youngster really thought of the situation.

Now he faces a dilemma. Will his powers prevent him from ever finding love?

How can we, as limited humans, tell where we are along the line between love and lust?