"Perhaps, friend Daneel, but it is mere speculation. Can you supply a possible motive for his action, then?"
"I can. I believe he inquired as to his descent, not to convince an implacable Dr. Amadiro but to convince himself."
"In that case, why should he have mentioned Dr. Amadiro at all? Why not simply have said, 'I wish to know.'?"
A small smile passed over Daneel's face, a change of expression of which the other robot would have been incapable. Daneel said, "Had he said, 'I wish to know,' to Madam Gladia, she would surely have replied that it was none of his business and he would have discovered nothing. Madam Gladia, however, is as strongly opposed to Dr. Amadiro as Dr. Amadiro is to Elijah Baley. Madam Gladia would be sure to take offense at any opinion strongly held by Dr. Amadiro concerning her. She would be furious, even if the opinion were more or less true; how much more, then, if it were absolutely false, as in this case. She would labor to demonstrate Dr. Amadiro to be wrong and would present every piece of evidence needed to achieve that end.
"In such a case, Dr. Mandamus's cold assurance that each piece of evidence was insufficient would but make her the angrier and would drive her to further revelations. Dr. Mandamus's strategy was chosen to make certain he would learn the maximum from Madam Gladia and, at the end, he was convinced that he did not have an Earthman as ancestor; at least, not as recently as twenty decades ago. Amadiro's feelings in this regard were not, I think, truly in question."
Giskard said, "Friend Daneel, this is an interesting point of view, but it does not seem to be strongly founded. In what way can we conclude that it is no more than a guess on your part?"
Daneel said, "Does it not seem to you, friend Giskard, that when Dr. Mandamus ended his inquiry into his descent without having obtained sufficient evidence for Dr. Amadiro, as he would have had us believe, that he should have been distinctly depressed and disheartened? By his own statement, this should have meant he had no chance for advancement and would never gain the position as head of the Institute of Robotics. And yet it seemed to me that he was far from depressed but was, indeed, jubilant. I can only judge by outward appearance, but you can do better. Tell me, friend Giskard, what was his mental attitude at the conclusion of this portion of his conversation with Madam Gladia?"
Giskard said, "As I look back on it, it was not only jubilant but triumphant, friend Daneel. You are right. Now that you have explained your process of thought, that sensation of triumph I detected clearly marks the accuracy of your reasoning. In fact, now that you have marked it all out, I find myself at a loss to account for my inability to see it for myself."
"That, friend Giskard, was, on a number of occasions, my reaction to the reasoning of Elijah Baley. That I could carry through such reasoning on this occasion may be, in part, because of the strong stimulus of the existence of the present crisis. It forces me to think more cogently."
"You underestimate yourself, friend Daneel. You have been thinking cogently for a long time. But why do you speak of a present crisis? Pause a moment and explain. How does one go from Dr. Mandamus's feeling of triumph at not being descended from Mr. Baley to this crisis you speak of?"
Daneel said, "Dr. Mandamus may have deceived us with his statements concerning Dr. Amadiro, but it may be fair to suppose that it is nevertheless true that he longs for advancement; that he is ambitious to become head of the Institute. Is that not so, friend Giskard?"
Giskard paused a moment, as though in thought, then said, "I was not searching for ambition. I was studying his mind without particular purpose and was aware of only surface manifestations. Yet there might have been flashes of ambition there when he spoke of advancement. I do not have strong grounds for agreeing with you, friend Daneel, but I have no grounds at all for disagreeing with you."
"Let us accept Dr. Mandamus as an ambitious man, then, and see where that takes us. Agreed?"
"Agreed."
"Then does it not seem likely that his sense of triumph, once he was convinced that he was not descended from Partner Elijah, arose from the fact that he felt his ambition could now be served. This would not be so, however, because of Dr. Amadiro's approval, since we have agreed that the Dr. Amadiro motif was introduced by Dr. Mandamus as a distraction. His ambition could now be served for some other reason."
"What other reason?"
"There is none that arises out of compelling evidence. But I can suggest one as a matter of speculation. What if Dr. Mandamus knows something or can do something that would lead to some huge success; one that would surely make him the next head? Remember that at the conclusion of the search into the manner of his descent, Dr. Mandamus said, 'There are powerful methods remaining to me.' Suppose that is true, but that he could only use those methods if he were not descended from Partner Elijah. His jubilation over having been convinced of his nondescent would arise, then, from the fact that he could now use those methods and assure himself of great advancement."
"But what are these powerful methods, friend Daneel?"
Daneel said gravely, "We must continue to speculate. We know that Dr. Amadiro wants nothing so much as to defeat Earth and force it back to its earlier position of subservience to the Spacer worlds. If Dr. Mandamus has a way of doing this, he can surely get anything he wants out of Dr. Amadiro, up to and including a guarantee of succession to the headship. Yet it may be that Dr. Mandamus hesitates to bring about Earth's defeat and humiliation unless he felt no kinship to its people. Descent from Elijah Baley of Earth would inhibit him. The denial of that descent frees him to act and that makes him jubilant."