Beware of attempting anything (in literary composition) for which nature has not gifted you—i.e., against the grain.
Notes from Wikiquote
Nihil decet invita, ut aiunt, Minerva, id est, adversante et repugnante natura. Cicero, de Officiis 1, 31, 110—Nothing that we write in the teeth of Minerva, as they say, i.e., against our natural capacities, will do us credit. Boileau, in imitation, begins his L’Art Poétique with
C’est en vain qu’ au Parnasse un téméraire auteur
Pense de l’art des vers attaindre la hauteur.
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Si son astre en naissant ne l’a formé poéte. | Excision