You must watch the whole of Enterprise to grok the full arc of the Temporal Cold War with 13 episodes that were more temporal than others:
Old T’Pol: There’s a human expression: Follow your heart.
Young T’Pol: What if my heart doesn’t know what it wants?
Old T’Pol: It will, in time, it will.

Variants

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  1. Star Trek: Enterprise by Rick Berman and Brannon Braga (26 September 2001).
  2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . written by Rick Berman