Originally Posted by Grand Dizzy:
“People’s personality can change drastically at any age.”
Yes. But Liz's didn't. After 10 years she always ended up in the same place, making the same choice: to condemn the whale and save her people.
Originally Posted by TimCypher:
“In another response in this thread, someone directed me to a film (ironically called 'Cypher') which they said would help explain why Liz 10, now, was a genuinely different person.”
For it's worth, the episode actually took the opposite view. Amy was to be dumped despite her not remembering what she did wrong. That means she was still the same person. The situation with Liz (and everyone else) was analogous. That's why the Doctor got angry at the whole human race: their forgetting did not get them off the hook. This wasn't spelt out for Liz, but what happened with Amy was a microcosm of what happened with Liz and that ought to have been enough.
The reason the Doctor didn't punish Liz is that she'd helped to save her people, a choice the Doctor understood and validated. She had no choice. His own solution wasn't much different (and would have led to the Doctor hating himself, to the point where he changed his name).
Quote:
“What we need to understand 'Doctor Who' should be *IN* 'Doctor Who'. It should have been in there, explored and explained.”
Not all the time. Sometimes it's OK to raise intriguing questions and leave them for the audience to think about. Especially if there are clues in the episode.