But Mike could never need to suicide, could not be drugged, did not feel pain. He carried everything concerning us in a separate memory bank under a locked signal programmed only to our three voices, and, since flesh is weak, we added a signal under which any of us could lock out other two in emergency. In my opinion as best computerman in Luna, Mike could not remove this lock once it was set up. Best of all, nobody would ask master computer for this file because nobody knew it existed, did not suspect Mike-as-Mike existed. How secure can you be?