Here, Oskar has just broken the vase which contains the key within the envelope labeled "Black": "'I didn't do it!' I hollered, but they didn't even hear me, because they were playing music too loud and cracking up too much. I zipped myself all the way into the sleeping bag of myself, not because I was hurt, and not because I had broken something, but because they were cracking up. Even though I knew I shouldn't, I gave myself a bruise." (37) This is the first of many incidents to follow.
I believe that (as said several times) Oskar bruising himself is a response to losing his father. Generally when he bruises himself it is for a very small reason such as dropping a vase.
I think that Oskar brusing himself has to do with the fact that he not only wants attention from his mom but wishes he could do something about everything that has happened in his life.
--This shows kind of the reason as to why he starts brusing himself. He wants the attention from people (mainly his mom), so by starting to bruse himself he can show the pain that he feels on the inside on the out, and that he wants people to recognize this pain.
Later on, when Oskar is trying to find out what the key he found is for, he goes back to the envelope the key was in. "It was then i noticed something that a good detective would have noticed at the very beginning: the word 'black' was written on the back of the envelope. I was so mad at myself for not noticing that i gave myself a little bruise." (41)
After Oskar got out the old home phone and started listening to his dad's messages, "[he] stared at the fake stars forever. [He] invented. [He] gave [him]self a bruise. [He] invented." (69)
-- I find it very scary that Oskar would bruise himself. He is just a little boy, and many bruises in the long term of his life could set him up for many problems, and possibly set him up for even more dangerous things. Additionally, I think that he, Oskar, is trying to bruise himself for not being able to save his dad from his unavoidable death in the twin towers.
At this point in the book Oskar is at Aaron Black's appartment and is dissapointed that Aaron doesn't know who his father was and didn't know anything about Oskar's key "I sat back down and started to cry in the lobby of an apartment building in Corona. I wanted to press all the buttons and scream curse words at everybody who lived in the stupid building. I wanted to give myself bruises." (90)
Here, Oskar is talking to the third Black of the day, and when he took a picture of the picture of the elephant on the wall in her house, she started to cry. "I bruise easily."(96) I guess he added this into there to calm down her crying, but I am not sure how it worked.
"I GUESS I FELL ASLPEEP ON THE FLOOR. WHEN I WOKE UP, MOM WAS PULLING MY SHIRT OFF TO HELP ME GET INTO MY PJS, WHICH MEANS SHE MUST HAVE SEEN ALL OF MY BRUISES. I COUNTED THEM LAST NIGHT IN THE MIRROR AND THERE WERE FORTY-ONE. SOME OF THEM HAVE GOTTEN BIG, BUT MOST OF THEM ARE SMALL. I DON'T PUT THEM THERE FOR HER, BUT STILL I WANT HER TO ASK ME HOW I GOT THEM (EVEN THOUGH SHE PROBABLY KNOWS), AND TO FEEL SORRY FOR ME (BECAUSE AT LEAST SOME OF IT IS HER FAULT), AND TO PROMISE ME THAT SHE WON'T DIE AND LEAVE ME ALONE. BUT SHE DIDN'T SAY ANYTHING. I COULDN'T EVEN SEE THE LOOK IN HER EYES WHEN SHE SAW THE BRUISES, BECAUSE MY SHIRT WAS OVER MY HEAD, COVERING MY FACE LIKE A POCKET, OR A SKULL." (172-173)
--This shows how Oskar feels his mom doesn't pay enough attention to him. He wants her to worry about him and feel guilty that she hasn't been caring for him. This relates to the central purpose of not being able to put what you feel into words.
Here, Oskar explains to Dr. Fein about "burry[ing] [his] feelings" (203) which he belives are interfering with his life: "No matter how much I feel, I'm not going to let it out. If I have to cry, I'm gonna cry on the inside. If I have to bleed, I'll bruise." (203) Bruising can be interpreted metaphorically, but readers will realize there is something more sinister behind Oskar's declaration.
--In this quote I find that Oskar is trying to find a way of beeding without bleeding. Throughout the story he keeps his emotions mostly to himself. Like the Hamlet incident, and many others. He doesnt want to bleed or cry on the outside either, so he keeps it inside. He can do this by bruising himself. I think more or less the brusing symbolized the pain that is inside of him that he is not yet ready to show to the world.
"Why didn't he say goodbye? I gave myself a bruise. Why didn't he say 'I love you'?" (207)
At this point Oskar found someone who knows about the key (it opens a safe-deposit box) and the person is asking Oskar some questions "'You found it in his closet?' 'Yes.' 'In a tall blue vase?' I nodded. 'With a label on the bottom?' 'I don't know. I didn't see a label. I don't remember.' If I'd been alone, I woudl have given myself the biggest brusie of my life. I would have turned myself into one big bruise." (295)
--His emotions have built up and he does not know what to do with them. I think that is what he is trying to say. He also does something like this with the heavy boots. I think his hope to connect with his father is lost and he has no other known way.
Here, Oskar makes small talk with Nancy Black at the cafe, and switches from subject to subject. "Mr. Black said, 'I'm going to get right to the point,' and then he did. I went to the bathroom and gave myself a bruise."(243)
Oskar bruises himself for a visual of the pain he is feeling inside that he can feel, but not see. So young, he doesn't know what to do with these over-whelming emotions.