Question: How did you view those people (that you infected with bubonic plague and dissected while still alive)? Didn't you have any feelings of pity?
Answer: None at all. We were like that already. I had already gotten to (a point) where I lacked pity. After all, we were already implanted with a narrow racism, in the form of a belief in the superiority of the so-called "Yamato Race." We disparaged all other races. ... If we didn't have a feeling of racial superiority, we couldn't have done it. People with today's sensibilities don't grasp this. ... We, ourselves, had to struggle with our humanity afterwards. It was an agonizing process. There were some who killed themselves, unable to endure."
— Tamura Yoshio, a member of biological warfare Unit 731, from "Japan at War: An Oral History"