Sunt etiam in Musis furiae. Thomas More's Latin was beyond my powers, but I thought this expression was worth sharing. Here's the Yale Edition's translation of More's poem, itself a translation from the Greek:
Even among the Muses there are Furies,
and it is they who make you the poet you are
and inspire you to write many poems without thought.
Come now, I entreat you, write ever so many poems,
for I find no greater fury to entreat for you than that.
103 "In Poetam Fvriosvm" E Graeco
Sunt etiam in Musis furiae, quibus ipse poeta
Fis, per quas temere carmina multa facis.
Ergo age plurima scribe precor, tibi nempe furorem
Non ego maiorem quem precer inuenio.