Because forgetting that he had killed Jimmy was essential to his plan to kill Teddy, the man who had been exploiting Leonard for his own personal gain.
You may be sure he killed the original John G., but I am not. I think we can be pretty sure he killed at least one other person before Jimmy, hence the Polaroid of blood, happy Leonard, but we only have Teddy’s word that it was the real John G. Even if you trust that Teddy is being honest in that scene (which I don’t), you can’t be sure he’s correct about John G.'s identity.
It’s also entirely possible that Teddy interfered with Leonard’s attempts to record the success of the first killing. After all, Teddy was the one with the tell-tale Polaroid, and he was the one who hoped to profit from Leonard’s killing of Jimmy. Was the Polaroid a morbid souvenier, or did Teddy take it from Leonard so Leonard would not realize that he’d already killed someone?
I was under the impression Teddy/John G kept Leonard killing in the search for Leonard’s revenge (long after he obtained it and forgot) for his own personal gain (ie: bumping off drug rivals). I don’t think Leonard knew he was a killing machine until the end of the film (beginning of the story) when Teddy told him he was. Leonard then got pissed and promptly set a ‘trap’ to trick himself into thinking Teddy was the John G he was looking for, thereby getting his revenge…even if he won’t remember it.
All that said, I truly think a lot of things are left ambigious on purpose to cause these sort of discussions among people. It’s very much like the contents of the suitcase in Pulp Fiction, the FedEx package contents in Cast Away, or the “did he / didn’t he” argument that breaks out after anyone sees ‘American Psycho’. It’s all movie making intended to have a reaction with people again and again. I love movies like this!
I think the very fact that Leonard sets himself up to kill Teddy indicates his repugnance at the idea of being a serial killer; otherwise, why would he be pissed? If he really felt that killing was the only thing giving his life meaning, he’d have no (logical) reason to be mad at someone who helped feed that urge. Also, as someone else pointed out, we have no evidence of him ever purposely destroying any other photos to continue his search. Thus, I don’t think he’s psychotic; just vengeful.
He might have been angered at Teddy shattering the delusion that Lenny had set up for himself. Leonard isn’t conscious of the fact that he keeps killing and killing, but it might be somewhere in his subconscious. I’m pretty sure my reasoning for that came out of Lenny’s whole “remember Sammy Jenkis” story, but it’s been a while since I’ve seen the movie, I’m going to have to watch it again.
Haha, the complications of this film can be so annoying to explain - I was just thinking that we don’t even know that there really IS a John G. What’s Teddy say to Leonard in the ‘first’ scene? He says something about Leonard’s wife being killed by some kids on drugs, and that he felt sorry for Leonard, so he helped him find someone to kill (he says for pity, it’s quite likely he had a selfish reason as well). But of course, Leonard couldn’t remember what happened just because he wanted to, so…
I said there was no logical reason, shy guy, remember?
Does “Hey! You demolished my fantasy world, now I’m going to kill you!” sound logical?
Still, just because it’s not logical doesn’t mean it’s not a possibility. However, if this were the reason he decided to kill Teddy, and not that he was repulsed by the fact that he’d been used as a killing robot, I believe it would follow that Leonard was psychotic, and while that’s also a possibility, it’s not one I would particularly entertain. Given the circumstances, it seemed like a rational enough choice…but that’s only because I assume it’s based on a rational motivation, so perhaps it’s something of a circular argument.
I’m with nevermore there. It’s not indicative of good mental health for Leonard by any stretch - I’d say it means he’s come unhinged. But that’s how I think a lot of people react if their worlds crumble like Leonard’s does. He’s told his life is a lie, that the purpose he’s given himself is a failure, and that he’s been thoroughly used as a serial killer. That’d probably push a lot of people over the edge.
Ah, very true, Marley23. His choice can still be regarded as rational, even if the driving force was irrational, because at this point it would be completely rational to be irrational, which I guess was sort of my point earlier. In such a situation, insanity would be sane…thus he could not be considered insane for his actions.
See, if I said stuff like this at home, I’d be smacked with a pillow and called a dork.
THIS is why I love the Straight Dope.
Well there’s already been enough help understanding wtf was going on in the movie, so I’ll use this as an opportunity to hijack say I loved that movie (and not just because Guy Pearce looked hot). One of my favorite parts is when Leoanrd is waking up with bottle in hand and says, “I don’t feel drunk.” Heh, gets funnier the second time.
Another fav is when the little guy (I forget the character’s name) exclaims “You tell everybody about Sammy Jenkis!!!” ::slaps knee:: That’s particularly funny since at another part in the film, Leonard demands proof that little guy isn’t a stranger and actually knows him. His proof is that he knows about Sammy Jenkis. Ha! But he tells everybody about Sammy Jenkis! Lucky thing that’s Leo’s memory ain’t so good.
