Keywords: 4Fold Root Figure 2m.gif en screenshot from p 102 of the pdf file download from archive org using maximal resolution 0 saturation maximal b/w contrast 1903 http //www archive org/details/onthefourfoldroo00schouoft Djvu file of Arthur Schopenhauer's essay On the Fourfold Root of the Principle of Sufficient Reason at archive org Arthur Schopenhauer other versions Custom license marker 2015 05 30 PD-old-100 Scans by User Jochen Burghardt On the Fourfold Root of the Principle of Sufficient Reason Uploaded with UploadWizard Optics diagrams of the human eye |