This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Fold Root Figure m. en screenshot from of the pdf file download from archive org using maximal resolution saturation maximal contrast archive org 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 marker PDold Uploaded