In terms of making progress towards solving the case, the large gap between Yukawa and Kusanagi is evident in their thought processes as they contemplate the case. Having gone their separate ways, with Yukawa in particular refusing to share the full depth of his insights with Kusanagi, Kusanagi and Yukawa are busy approaching the case from different perspectives, the one according a great deal of respect to Ishigami's genius and therefore grasping the full nature of the cover-up, the other still groping for answers and only just beginning to appreciate the full extent of Ishigami's brilliance.

It seems that Kusanagi questions Sonoka Sugimura in vain about Kudo and Ishigami, coming up empty-handed in terms of anything concrete that would be indicative of a link between Ishigami and Yasuko. Instead, he discovers the existence of a late-night phone call made by Yasuko to Sonoka that seems to support her alibi. It seems unlikely that Yasuko would neglect to mention such exonerating information, and Kusanagi begins to appreciate the depth of Ishigami's genius and the fact that so much of the case has been planned in such a way as to anticipate the every move of the police force. By contrast, Yukawa at this point is thorougly convinced of Ishigami's involvement in the cover-up, having had an appreciation for Ishigami's genius long since learning of Ishigami's connection to the case. Having no doubt about Ishigami's careful and foolproof planning, Yukawa is now interested in discovering Ishigami's motive for helping Yukawa. The fact that he asks Yusako why Ishigami is interested in her demonstrates his knowledge of Ishigami's involvement. For Yukawa, it is no longer a question of how Ishigami was involved but rather why. For Kusanagi, the investigation is still foundering on the issue of Yusako's alibi, and the role and full extent of Ishigami's involvement is only just beginning to dawn on him.

Yukawa uses circumlocution in speaking with Yusako, no longer acknowledging her pretense in pretending to not know Ishigami but instead speaking to her in a manner in which her cooperation is simply taken for granted. For example, when he leaves, he wryly says, "Say hi to Ishigami for me," which she attempts to deflect with her continuing pretense of having no relationship with him, which only comes across as hollow as Yukawa smiles with apparent amusement at her attempt to keep up the act. This causes Yasuko to wonder "how a man could make the simple act of walking away feel so intimidating." Simple gestures such as "walking away" can become "intimidating" for a genius who relies upon sheer force of wisdom in communicating. This is in contrast to the stereotype of a no-nonsense, hard-nosed detectives who gets answers by being agressive and pushy. Our traditional notion of "intimidating" is turned on its head through Yukawa's behavior, proving how our usual assumptions about human beings can exposed as shallow and inaccurate. It is these simplifying assumptions about human nature that prevents Kishitani from seeing Yasuko's a murderer and Kusanagi from considering the possibility that Ishigami might engage in murder as well.

Recalling a previous conversation with Yukawa, Kusanagi remembers Yukawa saying, Murder would've been [Ishigami's] last choice. Perplexed, Kusanagi asks, Why, because he's not vicious enough?" to which Yukawa answers, It's not a question of temperament. Murder isn't the most logical way to escape a difficult situation. It only leads to a different difficult situation. Ishigami would never engage in something so clearly counterproductive. Of course, the converse is also true. That is, he's quite capable of committing an atrocity, provided that it's the most logical course of action."

These words again further illustrate the fallacy of judging human beings according to the usual simplifying assumptions. For Kusanagi, committing murder is a matter of "not being vicious enough." Kishitani is guilty of making such a simplifying assumption about Yasuko, believing her to be too gentle and kind (i.e. "not vicious enough") to have murdered Togashi. Such simplifying assumptions cautions us against viewing human beings in moral as opposed to practical terms. Instead of problematizing human behavior with moral judgments, it is often more productive to seek an understanding for people's actions in which cause-and-effect is taken as one's starting point as opposed to any alleged morality or lack thereof. The amoral nature of logic is reflected here in Ishigami's statements above: as long as it represents the logical course of action, murder is very much within the bounds of possible actions that Ishigami might've taken, though it would've an illogical way to deal with someone like Togashi to begin with.

Kusanagi's inability to grasp Ishigami's potential for murder (vis-a-vis Yukawa) is mirrored by Kishitani's inability to grasp Yusako's connection to the murder of Togashi. Kusanagi bemoans the fact that his junior partner, Kishitani, is hopeless committed to Yasuko's innocence based on his conception of Yasuko as an affectionate single mother for whom murder represents a remote possibility. It was no use expecting anything like an objective opinion from the man now, Kusanagi reflects, exasperated with the closed-mindedness and naivete of his partner. Ironically enough, Kusanagi is just as closed-minded and naive in his inability to conceive of Ishigami emplying murder as tactic necessitated by logic. Both Kishitani and Kusanagi have failed to accurately assess the character of the people who are suspects in the case, being blinded by their own assumptions regarding how humans behave.

The tendency to misjudge other human beings based on one's own preconceptions of how people should or would behave shows afflicts several characters in the book. Yasuko can't quite understand why Ishigami would take such an interest in herself, seeing herself an an ordinary woman past her prime and not worthy of great admiration. Kishitani can't understand how Yasuko could be capable of killing Togashi, failing to appreciate the degree to which Togashi' persistent harassment combined with difficult cirumstance might have compelled her to act in unusual ways. Kusanagi can't understand how Ishigami might resort to murder for the sake of a woman, regarding such a course of action as being too extreme for someone with a simple crush on a woman. Each character, in his own way, lacks the empathy needed to appreciate the motives underlying other people's actions, and this empathy begins simply by considering, from a practical point of view, what factors might lead to people behaving a certain way. An amoral perspective on human action is not only not mutually exclusive with empathy but rather the starting point for developing a capacity for true empathy.