Editing Upanishads (section)

===Chronology===
Scholars are uncertain about when the Upanishads were composed.{{sfn|Olivelle|1998|pp=12-13}} The chronology of the early Upanishads is difficult to resolve, states philosopher and [[Sanskritist]] Stephen Phillips,<ref name="stephenphillips">Stephen Phillips (2009), ''Yoga, Karma, and Rebirth: A Brief History and Philosophy'', Columbia University Press, {{ISBN|978-0231144858}}, pp. 25-29 and Chapter 1.</ref> because all opinions rest on scanty evidence and analysis of archaism, style and repetitions across texts, and are driven by assumptions about likely evolution of ideas, and presumptions about which philosophy might have influenced which other Indian philosophies. Indologist [[Patrick Olivelle]] says that "in spite of claims made by some, in reality, any dating of these documents [early Upanishads] that attempts a precision closer than a few centuries is as stable as a house of cards".<ref name="olivelleintro">Patrick Olivelle (2014), ''The Early Upanishads,'' Oxford University Press, {{ISBN|978-0195124354}}, pages 12-14.</ref>

Some scholars have tried to analyse similarities between Hindu Upanishads and Buddhist literature to establish chronology for the Upanishads.{{sfn|King|1995|p=52}} Precise dates are impossible, and most scholars give only broad ranges encompassing various centuries. [[Gavin Flood]] states that "the Upanisads are not a homogeneous group of texts. Even the older texts were composed over a wide expanse of time from about 600 to 300 BCE."<ref>Flood, Gavin D. (2018). ''An Introduction to Hinduism'', p. 40, Cambridge University Press.</ref> Stephen Phillips places the early or "principal" Upanishads in the 800 to 300 BCE range.<ref name="stephenphillips" />

[[Patrick Olivelle]], a Sanskrit [[Philology|Philologist]] and [[Indology|Indologist]], gives the following chronology for the early Upanishads, also called the [[Principal Upanishads]]:{{sfn|Olivelle|1998|pp=12-13}}<ref name="olivelleintro" />
* The [[Brhadaranyaka Upanishad|''Brhadaranyaka'']] and the [[Chandogya Upanishad|''Chandogya'']] are the two earliest Upanishads. They are edited texts, some of whose sources are much older than others. The two texts are pre-Buddhist; they may be placed in the 7th to 6th centuries BCE, give or take a century or so.{{sfn|Olivelle|p=xxxvi|1998}}{{sfn|King|1995|p=52}}
* The three other early prose Upanishads—''Taittiriya, Aitareya'', and ''Kausitaki'' come next; all are probably pre-Buddhist and can be assigned to the 6th to 5th centuries BCE.<ref>Patrick Olivelle (2014), ''The Early Upanishads,'' Oxford University Press, {{ISBN|978-0195124354}}, pp. 12-13.</ref>
* The Kena is the oldest of the verse Upanishads followed by probably the Katha, Isa, [[Shvetashvatara Upanishad|Svetasvatara]], and Mundaka. All these Upanishads were composed probably in the last few centuries BCE.<ref>{{Cite web|url=https://www.britannica.com/topic/Upanishad|title=Upanishad &#124; Hindu religious text &#124; Britannica|website=www.britannica.com|date=23 May 2023 }}</ref> According to Olivelle, "All exhibit strong [[Theism|theistic]] tendencies and are probably the earliest literary products of the theistic tradition, whose later literature includes the Bhagavad Gita and the Puranas."<ref>Patrick Olivelle (2014), ''The Early Upanishads,'' Oxford University Press, {{ISBN|978-0195124354}}, p. 13.</ref> 
* The two late prose Upanishads, the Prasna and the Mandukya, cannot be much older than the beginning of the common era.{{sfn|Olivelle|1998|pp=12-13}}<ref name="olivelleintro" />
Meanwhile, the Indologist [[Johannes Bronkhorst]] argues for a later date for the Upanishads than has generally been accepted. Bronkhorst places even the oldest of the Upanishads, such as the ''Brhadaranyaka'' as possibly still being composed at "a date close to [[Kātyāyana|Katyayana]] and [[Mahābhāṣya|Patañjali]] [the grammarian]" (i.e., {{circa}} 2nd century BCE).<ref name="Bronkhorst" />

The later Upanishads, numbering about 95, also called minor Upanishads, are dated from the late 1st-millennium BCE to mid 2nd-millennium CE.{{sfn|Olivelle|1992|pp= 5, 8–9}} [[Gavin Flood]] dates many of the twenty [[Yoga]] Upanishads to be probably from the 100 BCE to 300 CE period.{{Sfn|Flood|1996|p=96}} [[Patrick Olivelle]] and other scholars date seven of the twenty [[Sannyasa#Sannyasa Upanishads|Sannyasa Upanishads]] to likely have been complete sometime between the last centuries of the 1st-millennium BCE to 300 CE.{{sfn|Olivelle|1992|pp= 5, 8–9}} About half of the Sannyasa Upanishads were likely composed in 14th- to 15th-century CE.{{sfn|Olivelle|1992|pp= 5, 8–9}}