Taer'thaiemenh was a work of literature by the Romulan author V. Raiuhes Ahaefvthe. Book 18, paragraph 886 of the text read in the original Romulan:

Daisemi'in rhhaensuriuu
Rh'e Mnhei'sahe yie ahr'en:
Mnahe afw'ein qiuu;
Rh'e hweithnaef
Mrht Heis'he ehl'ein qiuu.

This was translated by Janíce Kerasus as "Of the chief Parts of the Ruling Passion, only this can be truly said: Hate has a reason for everything. But love is unreasonable." (TOS novel: My Enemy, My Ally)

My Enemy, My Ally uses the above line as an epigraph at the start of the novel.