Romanticism was an intellectual movement that arose in the late eighteenth century and continued through the nineteenth century. The movement had roots in the arts, literature, and science. Largely conceived as a reaction towards the extreme rationalism of the Enlightenment, it championed expressing emotions through aesthetic and emphasizing the transcendent allure of the natural world.
There has been significant work done by historians about how romanticism played a significant role in the development of modern theories of evolution. Most notable is the work done by Robert J. Richards, a professor at the University of Chicago. Richards, and others, have contributed significantly to the conversation about how Romanticism plays a significant role in evolution theory, especially regarding German Romanticism.
Alexander von Humboldt
Romantic contributions to Darwin's theory of evolution
Charles Darwin became acquainted with Humboldt's exploration and science during while studying at Cambridge. Here, Darwin was taken under the direction of John Stevens Henslow (1796–1861), Professor of Botany, who strongly encouraged Darwin to travel and study nature. Henslow also encouraged Darwin to read Alexander von Humboldt's manuscripts on exploring nature, and it was, at least in part, Humboldt's work that inspired Darwin's romantic notion of travel and discovery.
Prior to Darwin's departure on the H.M.S. Beagle, Henslow bestowed to Darwin the English translation of Humboldt's Relation historique du voyage aux regions equinoxiales du nouveau continent, which the translator (Helen Maria Williams) called Personal Narrative of Travels to the Equinoctial Regions of America. Darwin read Humboldt's Personal Narrative thoroughly while on his own journey of scientific exploration on board the Beagle.
Interactions through letters
Darwin and Humboldt spent their later years exchanging letters and manuscripts. After reading Darwin's writings from the Beagle, Humboldt wrote to Darwin: “You told me in your kind letter that, when you were young, the manner in which I studied and depicted nature in the torrid zones contributed toward exciting in you the ardor and desire to travel in distant lands. Considering the importance of your work, Sir, this may be the greatest success that my humble work could bring. Works are of value only if they give rise to better ones.
The two men finally met in person in 1842. Humboldt died in 1859, sixth months before the first edition of On the Origin of Species was published. In letters to his close friend Joseph Dalton Hooker, Darwin reflected that his "whole course of life" was due to having read Humboldt's Personal Narrative and conclusively praised Humboldt as the "Greatest scientific traveller who ever lived."
Romantic style in evolution theory
Historians have noted that Humboldt's vision of aesthetic appraisal and science was incredibly comprehensive and modern for his time: consequently, his work contributed to advancing observation in geography, geophysics, and natural history. It has also been noted that Darwin's aesthetic approach to the natural world through his explorations and consequent observations was influenced by Humboldt's excursions and literature.
Johann Wolfgang von Goethe
Johann Wolfgang von Goethe (28 August 1749 – 22 March 1832) was a German Romantic poet, playwright, novelist, scientist, artist, and statesman whose works contributed significantly to natural history.
Romantic contributions to evolutionary science
Morphology
In 1790, Goethe wrote Versuch die Metamorphose der Pflanzen zu erklären (Metamorphosis of Plants) and Zur Morphologie, creating the scientific field of morphology, the branch of study in biology that deals with the structural forms of organisms. In his texts, Goethe used morphology to describe homology between parts of different organisms (for example, comparing the arm of a human to the fin of a whale). Goethe further suggested that adaptive modifications in an organism's parts were all relative to a Bauplan, an idealized, common archetype. Robert J. Richards suggests that Versuch die Metamorphose der Pflanzen zu erklären transformed biological sciences during this time period. Historian Joan Steigerwald suggests that Goethe's morphology was inherently Romantic, as they were idealistic. She also argues that Goethe's experiences with nature and aesthetics were the driving factors in his postulation of an "ideal" form (the Bauplan).