Did they really see it?

[PlaneJane22]

Reading the posts on the Jack/Ethan fight made me wonder about other things that characters have seen/heard that may not really be there.

So far:

-The Fight
-Jack's Dad
-Claire's Attacker
-The Moth
-Sayid's Voices
-Whatever Locke saw that time in the jungle

Anything else? Is the island inducing hallucinations or are they really seeing some or all of these things.

[Shadow1138]

Didn't Michael get "chased" by the "monster" at one point and ran into the asian woman bathing?

[sawyerhasbestlines]

Not that she saw her husband per se, but Rose seemed convinced her husband is alive - maybe she saw him the way Jack saw his dad.

[Hawkmistress]

It has also been speculated on this board that Danielle may have been a figment of Sayid's imagination.

Could be that the metal hull or trapdoor or whatever that Locke and Boone found is also something they are imagining or that is being put into their heads.