Sayid kills Dogen & Lennon clearing the way for Smokey

At the temple, many of the others are scrambling to gather their belongings to join Locke before sundown. Lennon tries to tell them that they're all safe as long as they stay at the temple, but even Cindy is not buying it.

Sayid goes inside to the spring, where Dogen is sitting on the steps holding the baseball. Sayid sits the dagger on the ground and Dogen says that Sayid let Locke talk to him (so, it would have actually worked if Locke hadn't spoken before being stabbed?).

Dogen tells Sayid that he was once a successful  business man in Osaka but after drinking to much at a celebration for a promotion, got into a wreck after picking his 12-year-old son up from baseball practice (that was likely his son we saw in the flash-sideways in "Lighthouse"). His son was badly hurt or possibly dead when Jacob approached him at the hospital and offered to heal his son, but in return, Dogen would have to come to the island and never see his son again (sounds a little like Juliet's story, minus the personal contact with Jacob).

Dogen then asks Sayid if he will stay or go and after Sayid seemingly sincerely says that he'll stay, he grabs Dogen and drowns him in the spring. Dogen releases the baseball in the water as he dies. Lennon then comes running in, berating Sayid for what he'd done. Lennon says that Dogen was the only thing keeping "him" (Locke) out. When Lennon is distracted by the warning sound of the smoke monster, Sayid slits his throat with the dagger and his body falls in the spring. Sayid has clearly gone dark.

So how exactly was Dogen the only thing keeping Locke out of the temple? Is he somehow responsible for the ash? If Locke's team really is the evil side, Sayid has very clearly joined it in a very dark way. He seems a bit like Michael in season 2. Sayid is willing to do anything, even murder, to get Nadia back.

Dogen doesn't kill Sayid, his baseball drops to floor

Sayid marches into Dogen's office at the temple and demands answers. He asks about the tests they performed on him and Dogen says that their is a scale of good to evil and the test showed that Sayid's scale was tipping towards evil. Dogen says it would be best if Sayid was dead.

Dogen then attacks Sayid and lengthy fight unfolds, culminating in Dogen holding a knife to Sayid's neck. Dogen's baseball falls to the floor though, which seems to cause Dogen's demeanor to suddenly change. He tells Sayid to leave to the temple and never come back. He lets Sayid go and picks up the baseball.

Dogen spins a baseball + Jack takes poison pill

Back in Dogen's office, he is spinning a baseball and concentrating on it. It seems likely that he is using it to think about thinks, much like Sawyer says he reads books to do the same in season 5. On the table, there are some written pages and the top one is slightly visible, but at a bad angle. If anyone can translate the Japanese, leave a comment.

Jack comes in and says that Dogen speaks good English for someone who needs and translator. Dogen tells him that he doesn't need one and he does it to remain separate from the people he's in charge of because it makes it easier when they don't like the decisions he makes for them.

Dogen tells Jack that he was brought to the island like everyone else. When Jack questions what that means, Dogen says that Jack knows exactly what he means. This seems to spook Jack.

Jack once again questions what is in the pill and Dogen says that he can't explain. Dogen says that Jack needs to trust him and Jack says that he doesn't trust himself. Jack then tries to swallow the pill and Dogen quickly springs into action, hitting Jack in the chest and performing the heimlich maneuver until the pills comes out. Dogen then admits that it's poison.

So why exactly do they want to poison Sayid? What exactly did their previous "test" tell them?