One of the most important questions to be asked in this story is whether or not Aaron Wechler sent the bomb to his former working place or not. There are several reasons to believe he did not. For instance, the declaration he gave the police was an exact paraphrase of what he read in the newspapers. This does point in the direction that Aaron did have nothing to do with the actual bombing. He also tells himself that he couldn’t have come up with such a brilliant scheme.
Another remarkable thing we can read near the end of the story is that Aaron burns the diary in which he described him killing all of his colleagues. This can be explained by knowing that he didn’t sent the bomb, but wanted to be sentenced for it. If the police would find his diary, they might assume that Aaron did not sent the bomb, for the profile and means of murder in his diary won’t probably match the bombing. After burning his original diary, he starts collecting newspaper articles concerning the bombing to, in a way, replace his earlier diary.
Talking about the diary, formally, we notice a couple of strange things. Firstly, it’s quite awkward that he keeps his diary in a ledger, something that people would normally use to keep up with their financial records. This indicates that he does not feel any compassion for the people he thought to have murdered, but sees everything more as a business. The style of his handwriting, which is small and carefully written down, also implies that he has (or thinks he has) total control.
Another strange instance in the text is the mentioning of the machine. This machine is described, and focalised, as an almost extra human torturing machine. Aaron himself doesn’t know however what this machine is for, which is strange because there is also mentioned that he used the machine at least once before. This only adds up to his dubious state of mind because he (accidentally or non-accidentally) blocks of memories. This also happens with several other things...