Encyclopaedia Britannica: Neoplatonism
Comprehensive overview of the Neoplatonic philosophical system, its origins in Plotinus, and its influence on Christian, Islamic, and Jewish mysticism.
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Neoplatonism (Stanford Encyclopedia of Philosophy)
Stanford Encyclopedia entry on the Neoplatonic philosophical tradition from Plotinus through Proclus and its lasting influence.
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Plotinus's collected philosophical writings organized by his student Porphyry — the foundational texts of Neoplatonic philosophy.
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