Sources and licences
Overviews: Wikipedia
Overviews of ideas and philosophers are adapted from Wikipedia and are available under the Creative Commons Attribution-ShareAlike 4.0 licence. Every page links its source article, where the list of authors is in the page history. Our adaptations are shared under the same licence.
Books: Project Gutenberg
Book texts come from Project Gutenberg. They are in the public domain in the United States. Copyright terms differ between countries; if you are outside the United States, check the rules where you live before reusing a text. Each book page links to its Project Gutenberg page.
Pictures: Wikimedia Commons
We show a picture only when its licence allows it (public domain, CC0 or Creative Commons with credit), and we show the creator, the licence and a link to the original beside it. Pictures generated by software are never used as portraits of real people.
Passage links
Which passage belongs to which idea is our own work, made by search and checks; it is not part of the books or of Wikipedia.
Correcting or removing something
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