FOUR VOLUME SET. All volumes contain a b&w woodcut with depictions of ancient Greek philosophers as frontispiece. [ALL VOLUMES]: 140x90mm. [CXXXVI+227] + [347] + [364] + [365] pages. Original green leather Hardcover with gilt spine and framing. Cover and spine rubbed. Cover corners and edges bumped and peeling/worn. Spine edges peeling. Inner cover age-stained. Pages yellowing, age-stained and wavy. [VOL.I]: Front cover almost detached. Pencil inscriptions on front whitepage. Second front whitepage upper edge edge slightly missing and torn. [VOLS.I&II]: Spine bottom half missing. [VOL.II]: Binding visible between frontispiece, title-page and page 1. [VOL.III]: Binding coming slightly visible on front inner cover. [VOL.IV]: Rear cover coming loose. Spine hinges cracked. Binding visible between frontispiece and title-page. [SUMMARY]: All volumes are otherwise in good reading condition.