2 questions: 1 about 2 episodes ago and 1 about last week's.

2 episodes ago: So, Alpert visited Locke because of Locke's time travel interaction with Alpert telling Alpert to go check him out when he's born? Or, Alpert found out about Locke anyway? If it's the first, then it's all just a circular thing then kind of like a time loop or whatever.

Last week's: Why were people questioning the fact that Danielle never recognized Jin? She never met Jin yet. It's like Alpert not recognizing Locke or any of the Losties. They didn't meet yet.