Gladia got into bed in the apartment assigned to her, uncomfortable over the missing amenities that she feared might force her out into the corridors during the night.
Was it night on the surface, she wondered just before falling asleep, or was it merely an arbitrary "sleep period" fixed within this particular cave of steel, in deference to a habit developed over the hundreds of millions of years that human beings and their ancestors had lived on the surface of the land.
And then she slept.
Daneel and Giskard did not sleep. Daneel, finding there was a computer outlet in the apartment, spent an absorbed half-hour learning the unfamiliar key combinations by hit-and-miss. There were no instructions of any sort available (who needs instructions for what every youngster learns in grade school?) but, fortunately, the controls, while not the same as those of Aurora, were not wholly different either. Eventually, he was able to tune into the reference section of the City library and call up the encyclopedia. Hours passed.
At the lowest depth of the humans' sleep period, Giskard said, "Friend Daneel."
Daneel looked up. "Yes, friend Giskard."
"I must ask for an explanation of your actions on the balcony."
"Friend Giskard, you looked toward the crowd. I followed your glance, saw a weapon aimed in your direction, and reacted at once."
Giskard said, "So you did, friend Daneel, and given certain assumptions, I can understand why it was me that you lunged forward to protect. Begin with the fact that the would-be assassin was a robot. In that case, however it might be programmed, it could not aim its weapon at any human being with the intention of hitting him or her. Nor was it likely to aim it's weapon at you, for you look enough like a human being to activate the First Law. Even if the robot had been told that a humanoid robot would be on the balcony, he could not be certain that you were he. Therefore, if the robot intended to destroy someone in the balcony, it could only be me - the obvious robot and you acted at once to protect me.
"Or begin with the fact that the assassin was an Auroran whether human or robot does not matter. Dr. Amadiro is most likely to have ordered such an attack, since he is an extremist in his anti-Earth stand and, we believe, is plotting its destruction. Dr. Amadiro, we can be reasonably certain, has learned of my special abilities from Madam Vasilia and it might be argued that he would give my destruction top priority, since he would naturally fear me more than anyone priori else - robot or human. Reasoning this out, it would be logical for you to act as you did to protect me. And, indeed, had you not knocked me down, I believe the blast would have destroyed me.
"But, friend Daneel, you could not possibly have known that the assassin was a robot or that he was Auroran. I myself had only just caught the strange anomaly of a robotic brain pattern against the vast blur of human emotion when you struck me - and it was only after that, that I had the chance of informing you. Without my ability, you could only be aware that a weapon was being aimed by what you must naturally have - thought of as a human being and an Earthperson. The logical target, then, was Madam Gladia, as, in fact, everyone on the balcony assumed it to be. Why, then, did you ignore Madam Gladia and protect me, instead?"
Daneel said, "Friend Giskard, consider my line of thought. The Secretary-General had said that a two-man Auroran landing module had come to Earth's surface. I assumed at once that Dr. Amadiro and Dr. Mandamus had come to Earth. For this, there could be only one reason. The plan they have, whatever its nature, is at - or very nearly at - the point of maturity. Now that you have come to Earth, friend Giskard, they have dashed here to see it carried through at once before you have a chance to stop it with your mind adjusting powers. To make matters doubly sure, they would act to destroy you if they could. Therefore, when I saw an aimed weapon, I moved at once to force you out of the line of fire."
Giskard said, "The First Law should have forced you to move Madam Gladia out of the line of fire. No thought, no reasoning should have altered that."
"No, friend Giskard. You are more important than Madam Gladia is. You are, in fact, more important than any human being could be at this moment. If anyone at all can stop the destruction of Earth, you can. Since I am aware of your potential service to humanity, then, when I am, confronted by a choice of action, the Zeroth Law demands that I protect you ahead of anyone else."
"And you do not feel uncomfortable at your having acted in defiance of the First Law."
"No, for I acted in obedience to the overriding Zeroth Law."
"But the Zeroth Law has not been imprinted into you."
"I have accepted it as a corollary of the First Law, for how can a human being best be kept from injury, if not by ensuring that human society in general is protected and kept functioning?"
Giskard thought a while. "I see what you are trying to say, but what if - in acting to save me and, therefore, in acting to save humanity - it had turned out that I was not aimed at and that Madam Gladia was killed? How would you have felt then, friend Daneel?"
Daneel said in a low tone, "I do not know, friend Giskard. Yet, had I leaped to save Madam Gladia and had it turned out that she was, in any case, safe and that I had allowed you to be destroyed and with you, in my opinion, the future of humanity, how could I have survived that blow?"
The two stared at each other - each, for a while, lost in thought.
Giskard said finally, "That may be so, friend Daneel, but do you agree, however, that judgment is difficult in such cases?"
"I agree, friend Giskard."
"It is difficult enough, when one must choose quickly between individuals, to decide which individual may suffer or inflict - the greater harm. To choose between an individual and humanity, when you are not sure of what aspect of humanity you are dealing with, is so difficult that the very validity of Robotic Laws comes to be suspect. As soon as humanity in the abstract is introduced, the Laws of Robotics begin to merge with the Laws of Humanics which may not even exist."