Ayn Rand held the 'romantic principle' as she called it very early in life, she grasped it first hand. Gradually as she read french novels she began to recognize the principe in the romantic movement in fiction. In addition, when she read Aristotle's poetics she saw it stated, "what could be and should be."
I can't tell you what is romantic in painting, or music, or sculpture. But fiction I am more familiar with. In fiction the clearest statement would be Victor Hugo's work and particularly his preface to his play Cromwell. Romanticism was something new in rebellion of Classicism. Some say that Goethe's The Sorrow of Young Werther (which I haven't read) is the first romantic work. But recently an Objectivist identified that Schiller's The Robbers is really the first romantic work in fiction.
There are two distinctive characteristics: The man is in control of his destiny and that he has free will over his values. I am not too familiar with specimens of Classicism, but I am familiar with Romanticism contrasted to Naturalism (which was a reaction to Romanticism). Naturalism clearly does not project the metaphysical view about man's destiny and free will. But Classicists were known to follow rigid rules allegedly borrowed from Aristotle that was detrimental to the originality of the work.
Is man pulled forward by his own values, or pushed forward by some deterministic power (outside or inside himself)? If you took a look at the works then known as Romantic from Hugo, Dumas, Schiller, and Rostand, you would see this principle at work.
A fiction work could advocate altruism as a moral ideal and condemn Capitalism and still be romantic and romantic-realist. It is the metaphysical view that is the key.
Ayn Rand is a Romantic because of this metaphysical principle found in her work. I would say she is a Realist because she is studying men according to the correct epistemology and therefore drawing men by essentials as she sees them in today's world, on this earth. Naturalists wanted to write about their time, to define it, and paint it as a scientific record. There is something important about writing for their time. Ayn Rand says that only Victor Hugo achieved it in the closest way to her with Les Miserables. Ayn Rand and Victor Hugo in this context are doing what the Naturalists or Realists are doing but their method is more accessible to all men.
As for the poets, I haven't studied them enough. Do they project free will? I do know that many of the Romantics are doing something different and new with their poetry. To what extent do their poetry allow for a metaphysical view? Perhaps it is in their style mainly.
Ayn Rand's stories clearly project values, the characters do exert their free will.
I wrote something sometime ago trying to define Romantic Realism:Thread on Romantic Realism
Edited by AMERICONORMAN, 25 October 2009 - 09:29 AM.
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