 Why does Quest say he is lucky?
“It was drawn into Jupiter, but he landed it successfully,” said Quest. “If Dr. Mansard succeeded in landing on Jupiter, why didn't anyone ever hear from him again?” she demanded. Dr. Mansard and his wife had disappeared into the turbulent atmosphere of Jupiter just after his invention of the surgiscope, and it had been developed by Dom Blessing. Through all these years since Dr. Mansard's disappearance, 55 Blessing had been searching the Jovian moons for a second, hidden laboratory of Dr. Mansard. Blessing would, of course, be happy to learn that a son of Dr. Mansard lived, and would see that he received his rightful share of the inheritance.
 Quest considers himself lucky that he did not commit murder. He is not a murderer at heart.
 Quest considers himself lucky that Trella is in love with him.  Quest considers himself lucky that he is not actually an android.  Quest considers himself lucky that Asrange did not kill him.  Quest considers himself lucky that he did not commit murder. He is not a murderer at heart.