Monism

=====Levels of truth=====
Within Buddhism, a rich variety of philosophical{{sfn|Williams|1994}} and pedagogical models{{sfn|Buswell|Gimello|1994}} can be found. Various schools of Buddhism discern levels of truth:
* The [[Two truths doctrine]] of the [[Madhyamaka]]
* The [[Three natures|Three Natures]] of the [[Yogacara]]
* [[Essence-Function]], or [[Chinese Chán#Absolute-relative|Absolute-relative]] in Chinese and Korean Buddhism
* The [[Trikaya]]-formule, consisting of 
** The ''[[Dharmakāya]]'' or ''Truth body'' which embodies the very principle of [[Enlightenment in Buddhism|enlightenment]] and knows no limits or boundaries;
** The ''[[Sambhogakāya]]'' or ''body of mutual enjoyment'' which is a body of bliss or clear light manifestation;
** The ''[[Nirmāṇakāya]]'' or ''created body'' which manifests in time and space.<ref name="Welwood, John 2007">Welwood, John (2000). [http://www.purifymind.com/PlayMind.htm ''The Play of the Mind: Form, Emptiness, and Beyond''], accessed January 13, 2007</ref>

The [[Prajnaparamita|Prajnaparamita-sutras]] and [[Madhyamaka]] emphasize the non-duality of form and emptiness: "form is emptiness, emptiness is form", as the [[heart sutra]] says.{{sfn|Liang-Chieh|1986|p=9}} In Chinese Buddhism this was understood to mean that ultimate reality is not a transcendental realm, but equal to the daily world of relative reality. This idea fitted into the Chinese culture, which emphasized the mundane world and society. But this does not tell how the absolute is present in the relative world:
{{blockquote|To deny the duality of samsara and nirvana, as the Perfection of Wisdom does, or to demonstrate logically the error of dichotomizing conceptualization, as Nagarjuna does, is not to address the question of the relationship between samsara and nirvana -or, in more philosophical terms, between phenomenal and ultimate reality [...] What, then, is the relationship between these two realms?{{sfn|Liang-Chieh|1986|p=9}}}}
This question is answered in such schemata as [[Five Ranks|the Five Ranks of Tozan]],{{sfn|Kasulis|2003|p=29}} the [[Ten Bulls|Oxherding Pictures]], and [[Hakuin#Four ways of knowing|Hakuin's Four ways of knowing]].{{sfn|Low|2006}}