An edited transcript of lectures recorded by the BBC in 1966—67, this book is editor Hardy’s (one of Isaiah Berlin’s literary trustees) commendable effort to preserve the legacy of one of the most prominent thinkers of the 20th century. Berlin searches for the sources of Romanticism primarily in Germany, focusing on Hamann, Kant, Herder, Fichte, Schiller, Schlegel, and others who contributed to the rise of the movement at the end of the 18th century. This break in European consciousness led to the replacement of Enlightenment-era objective criteria in the evaluation of human reason and beauty with individualistic, relativist, and mystical Romantic views. Proponents of Romanticism advocated the rejection of aesthetic rules, believed in emotionalism and the liberating function of art, and craved the infinite as embodied in myths. For them, the creative process entailed delving into the artist’s unconscious, and they espoused the idea that will, not reason, dominates life. Berlin points out the complexity of Romanticism, which embraces an infinite array of potentially conflicting aspects. He considers the obvious paradox between the valorization of the noble savage on the one hand, and the whimsical Gothic taste for extravagance and mysticism on the other. Both tendencies, however, reflected the Romantic urge to transgress the boundaries of dull, everyday existence by pointing to some unattainable, exotic reality. Among the offshoots of the Romantic worldview, Berlin mentions two powerful 20th-century phenomena: existentialism and fascism. Existentialism was rooted in the extreme Romantic view of the universe as void, while fascism can be traced back to Fichte’s patriotic diatribe calling upon the “younger, vigorous” German nation to conquer weaker, “decadent people.” Besides occasional plot summaries of prose works, Berlin does not illustrate his views with actual Romantic texts. His survey of Romanticism remains a fairly dry but exacting account of the ideas underlying the movement’s aesthetic sensibilities. Complicated by uneven syntax and repetitiousness betraying the genre of oral presentation, the book is a challenge even to the dedicated reader.