In presenting in Part I a brief survey of aesthetic theory in the 18th century in France, England and Germany, the author has made no effort to cover the entire field. Selection has been prompted by the desire to bring into relief the leading ideas of those writers who were thought to be of especial moment at the time Herder composed the forth Waldchen (1769), a procedure which was deemed necessary for a better understanding of the particular purpose of the thesis. The Fourth Waldchen has been examined in Part II with particular reference to previous theory, since it offers what amounts to documentary evidence with regard to the conscious relationship in which Herder stood with his contemporaries and predecessors in this field. The present work is the outcome of special studies prepared for the Herder Seminars..... Many of the earliest books, particularly those dating back to the 1900's and before, are now extremely scarce and increasingly expensive. We are republishing these classic w