"My dear Justin!" Ortine spread his hands wide. "Consider my position. What had originally been a most impersonal mission had become a matter of the deepest personal concern. Confidentially, I have never since—or at least within the past few hundred generations—been able to materialize on Earth itself."
"Why not?" Justin asked him.
"Because of the risk," replied Ortine. "Suppose, as a man, I were killed accidentally or murdered. Suppose, as a woman, I conceived again—I can assure you my desires in such matters are perhaps even stronger than those of your species.
"Each such accident—and in the early days I had my share—is weakening. I have only so much life force and no means of replenishing that which is spent—not in this universe. Hence I have had to indulge in what you might term economy of forces."
"Playing the devil...." Justin reminded him.
"Dammit, don't interrupt. I am quite capable of image projections—hallucinations to you. These I have indulged in frequently when I thought such appearances needful or considered them diverting. In some of them, for various reasons, I have assumed some remarkable shapes."
"How about these folk you can influence directly?"
Ortine regarded Justin irritably, said, "Surely you know enough of Mendel's Law to be aware that dominant strains will pop up again and again, even in a recessive capacity. When mine recurs, as it does in every generation, I am able to exercise over them more control than I can over others."
"How much control can you exercise over someone else—say over me?" Justin asked Ortine quietly.
"I think you can answer that for yourself," said Ortine.