The presocratics were early Greek philosophers active during or before the time of Socrates.
The following are some sources of information on presocratic philosophy.
- Wikipedia contributors. (2019, July 11). Pre-Socratic philosophy. In Wikipedia, The Free Encyclopedia. Retrieved 01:31, July 21, 2019, from https://en.wikipedia.org/w/index.php?title=Pre-Socratic_philosophy&oldid=905749452
- Curd, Patricia, "Presocratic Philosophy", The Stanford Encyclopedia of Philosophy (Summer 2019 Edition), Edward N. Zalta (ed.), URL = https://plato.stanford.edu/archives/sum2019/entries/presocratics/.
- Graham, Jacob, "Presocratics", Internet Encyclopedia of Philosophy, https://www.iep.utm.edu/presocra/
- Internet Archive. https://archive.org/search.php?query=Presocratics
