Traveling Through Time

    The gift of time travel also brings responsibility. The rules of time are fluid and complicated. Actions have consequences, and not all time is in flux - some tragedies cannot be reversed.
   The Doctor has prevented catastrophe from rewriting the future from Earth many times. He sees his relationship with humans as a strength, but his enemies regard it as a weakness that is easy to exploit.
   Some moments are temporal tipping points, where decisive action could create a new timeline. When the future pivots around human-Silurian negotiations for a cohabitation deal, the Doctor is hopeful for a new era on Earth.
   Some events are fixed and cannot be changed. The Doctor can only mourn and carry on. On Bowie Base One, the Doctor refuses to follow the rules of time and rescues the crew.

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