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Tree of knowledge system

a theoretical approach to the unification of psychology developed by Gregg Henriques, associate professor and Director of the Combined-Integrated Doctoral Program in Clinical and School Psychology at James Madison University

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Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionJul 26, 2026
Entity authorityQ7837602
Source-derived summary

The tree of knowledge (ToK) system is a new map of Big History that traces cosmic evolution across four different planes of existence, identified as Matter, Life, Mind and Culture that are mapped respectively by the physical, biological, psychological and social domains of science. The Tree of Knowledge (ToK) System was developed by Gregg Henriques, who is a professor and core faculty member in the Combined-Integrated Doctoral Program in Clinical and School Psychology at James Madison University. The ToK System is part of a larger Unified Theory of Knowledge that Henriques describes as a consilient scientific humanistic philosophy for the 21st Century.

The official Unified Theory of Knowledge website describes the ToK System as:

[A] theory of scientific knowledge that defines the human knower in relation to the known. It achieves this novel accomplishment by solving the problem of psychology and giving rise to a truly consilient view of the scientific landscape. It accomplishes this via dividing the evolution of behavioral complexity into four different planes of existence...The ToK also characterizes modern empirical natural science as a kind of justification system that functions to map complexity and change.

The outline of the ToK System was first published in 2003 in Review of General Psychology. Two special issues of the Journal of Clinical Psychology in December 2004 and January 2005 were devoted to the elaboration and evaluation of the model. In 2008, a special issue of Theory & Psychology was devoted to the ToK System. In 2011, Henriques published A New Unified Theory of Psychology.

Editorial summary

“Tree of knowledge system” enters the record as a theoretical approach to the unification of psychology developed by Gregg Henriques, associate professor and Director of the Combined-Integrated Doctoral Program in Clinical and School Psychology at James Madison University. Crown Archives preserves that source wording while asking what Tree, knowledge and system can confirm, complicate or overturn.

Editorial reviewA productive starting point for separating a subject’s documented career from later reputation and commemoration. The current lead gives the account dated anchors—2003, 2004, 2005, 2008—that can be checked directly. The selected authority fields contribute no independent date. Its strongest next move is a source search built around Tree, knowledge and system.
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“Tree of knowledge system” is worth following because a concise public description often conceals a longer documentary argument. Here, Tree, knowledge and system provides the most credible route into that argument.

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The entry’s evidential value lies in the named roles, institutions and publications that can be tested against primary documentation. The source revision retrieved here is dated Jul 26, 2026. The linked authority identifier is Q7837602. None of the 0 selected statements returned an explicit reference. The first chronological checks are 2003, 2004, 2005 and 2008.

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Public reputation and documentary evidence do not always develop together; absence from a summary is not evidence of historical absence. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

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This entry incorporates text from Tree of knowledge system” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.