Monism

==Monistic philosophers==

===Pre-Socratic===
While the lack of information makes it difficult in some cases to be sure of the details, the following [[Pre-Socratic philosophy|pre-Socratic philosophers]] thought in monistic terms:{{sfn|Abernethy|Langford|1970|pp=1–7}}
* [[Thales]]: Water
* [[Anaximander]]: ''[[Apeiron]]'' (meaning 'the undefined infinite'). Reality is some, one thing, but we cannot know what.
* [[Anaximenes of Miletus]]: Air
* [[Heraclitus]]: Change, symbolized by fire (in that everything is in constant flux).
* [[Parmenides]]: Being or Reality is an unmoving perfect sphere, unchanging, undivided.{{sfn|Abernethy|Langford|1970|pp=8–9}}

===Post-Socrates===
* Neopythagorians such as [[Apollonius of Tyana]] centered their cosmologies on the [[Monad (philosophy)|Monad]] or One.
* [[Stoics]] taught that there is only one substance, identified as God.<ref>{{Cite book|url=https://books.google.com/books?id=cbEGAAAAQAAJ&q=Stoics+taught+that+there+is+only+one+substance,+identified+as+God&pg=PA9|title=The popular Biblical educator [by J. Blackburn].|last=Blackburn|first=John|date=1854|language=en}}</ref>
* Middle Platonism under such works as those by [[Numenius of Apamea|Numenius]] taught that the Universe emanates from the Monad or One.
* [[Neoplatonism]] is monistic. [[Plotinus]] taught that there was an ineffable transcendent god, 'The One,' of which subsequent realities were emanations. From The One emanates the Divine Mind ([[Nous]]), the Cosmic Soul ([[Psyche (psychology)|Psyche]]), and the World ([[Cosmos]]).

===Modern===
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* [[Alexander Bogdanov]]
* [[F. H. Bradley]]
* [[Giordano Bruno]]<ref>''De la causa, principio e Uno, London, 1584''</ref><ref>''De monade (De monade, numero et figura liber consequens quinque de minimo magno et mensura), Frankfurt, 1591''</ref>
* [[Gilles Deleuze]]
* [[Friedrich Engels]]
* [[Johann Gottlieb Fichte]]
* [[Ernst Haeckel]]<ref>[https://archive.org/details/wonderslifeapop01haecgoog ''Wonders of Life''] by Ernst Haeckel.</ref><ref>[https://books.google.com/books?id=RdsdAAAAMAAJ The Evolution of Man: A Popular Scientific Study, Volume 2] by Ernst Heinrich Philipp August Haeckel.</ref>
* [[David Bentley Hart]]
* [[Georg Wilhelm Friedrich Hegel]]
* [[Christopher Langan]]
* [[Giacomo Leopardi]]<ref>{{Cite web|url=https://www.ft.com/content/ae962862-03fc-11e3-8aab-00144feab7de |archive-url=https://ghostarchive.org/archive/20221210/https://www.ft.com/content/ae962862-03fc-11e3-8aab-00144feab7de |archive-date=2022-12-10 |url-access=subscription |url-status=live|title=Review: Giacomo Leopardi's 'Zibaldone'|date=2013-08-16|website=Financial Times|language=en-GB|access-date=2018-05-05}}</ref>
* [[Ernst Mach]]
* [[Karl Marx]]
* [[Wilhelm Ostwald]]
* [[Charles Sanders Peirce]]
* [[Georgi Plekhanov]]
* [[Gilbert Ryle]]
* [[Jonathan Schaffer]]
* [[Friedrich Wilhelm Joseph Schelling]]
* [[Hans Jonas]]<ref name="S">Sariel, Aviram. "Jonasian Gnosticism." Harvard Theological Review 116.1 (2023): 91-122, here 99.</ref>
* [[Arthur Schopenhauer]]
* [[Rupert Sheldrake]]
* [[B.F. Skinner]]
* [[Herbert Spencer]]
* [[Baruch Spinoza]]
* [[Rudolf Steiner]]
* [[Alan Watts]]
* [[Alfred North Whitehead]]
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