>> guest: well, i had to track him down, and i think a--a journalist, ian buruma, actually, was the one who gave me his address, and i--i wrote a letter to him, i had it translated into japanese and and he responded im--almost immediately. and i had the letter translated back into english. he sent me a copy of his diaries. and he also answered every question that i had posed to him. see, i was to understand the--the--the state of mind that he was in at the time. c-span: what did you learn from him? >> guest: what i learned was that the japanese soldier really had to see the chinese as subhuman before they could kill them. i mean,he--he depicted the--the chinese in his diary as--you know, as like animals or as insects. c-span: right above that in the book, you can put this into context:'a veteran officer named tominga--no. tomini--tominiga shuso recalled vividly his own transformation from innocent youth to killing machine.' and i wanna read what you have in here. where did you find that, by the way? >> guest: that was in a secondary source. i think it came from abook. c-span: 'he scoope