Locke also never typed “space” at any point. Once the number was entered, the cursor moved on after a short amount of time.
A friend of mine had me go back and look it over. Mike puts the gun down on the makeshift raft after shooting the shark and then paddles over to Sawyer on the pontoon. So it’s certainly within Sawyer’s reach at that point. Next scene with them is as the sun is dawning and it looks like Sawyer has the gun in the back of his pants. Then they come ashore and he falls over on the sand and defintely has it there.
Personally, I don’t buy this idea of the hatch being a psychological experiment. I’ll admit, though, that the idea is certainly plausible and it wouldn’t surprise me if it turned out to be the case. But the guy in the film made three points, and the first two were correct, so why shouldn’t the third?
[ul]
[li]There’s a strange electro-magnetic force on the island that needs studying.[/li][li]Something bad happened while studying it (the mental disease)[/li][li]Therefore, entering the numbers and pressing the button is necessary.[/li][/ul]
So, assuming all this, here’s my theory: While working on testing the strange electro-magnetism field, the researchers set in motion a chain of events that cause the phenomenon to grow until, left unchecked, the field would engulf the entire world. Since the magentism seems to cause madness in those who are exposed to it, it would essentially mean the end of the world. Working quickly, the researchers find a way to neutralize it by shooting it with an electro-magnetic pulse (or some such Star Trekian concept) every so often to keep it under control. However, if not kept in check every 108 minutes, it would grow too big to be contained. The numbers entered are the frequency, signal pattern, whatever, of the pulse that is sent out. Since those working in the Swan station would be exposed to the magnetism as well, they need to take an antidote filled with material of the same frequency/signal-pattern/whatever. If you’ll notice… Jack started acting a little mad after his exposure to the magnet (i.e. when the key pulled away from his neck). So in order to keep the entire world safe, someone needs to put in those exact number every 108 minutes.
A flaw in my theory, though, is that Desmond already seems to think that the world’s ended anyway. Which implies to me he must have missed entering the numbers once. But then why didn’t he leave the hatch then? Or does he think the world ended for another reason?