This is a piece of early literary criticism which deals in particular with the very vexing question of whether a writer is able to learn their trade through application and hard work, or whether they have to possess an innate creativity and genius that cannot be learnt. The writer of this text argues that it is genius that makes a great writer, and he spends a lot of time arguing that a great writer who produces sublime literature knows when to let their innate creativity have free rein and also when to keep it in check. The text therefore explores the relationship between natural genius and poetic skills and techniques that can be learnt. Note how this is presented in the following quote:
Nature is the original and vital underlying principle in all cases, but system can define limits and fitting seasons, and can also contribute the safest rules for use and practice.
Longinus therefore believes that whilst "nature" or natural genius is thus vital for sublime literature to be created, at the same time, "system" or learnt skills such as rhyme and techniques are also very important to help shape and mould that genius and create sublime literature. The rest of the text explores the various characteristics of what it takes for a piece of literature to be "sublime."
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