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The Enlightenment Gap and Psychology's Metaphysical Problem

The Enlightenment gap and fixing the problem with psychology's metaphysics.

Thanks for clicking on the title of such an abstract-sounding blog! I hope that you will find what follows to be a clear articulation of important pieces of psychology’s history and that it explains some of the key reasons psychology has had some difficulty getting its concepts right and how we can fix the problem going forward.

Let me start by explaining the word “metaphysical”, because that word sounds academic and highbrow. “Metaphysics” is a formal branch of philosophy, and you don’t hear this word used in everyday conversation all that much. But it really should not be a scary word. In fact, I think it is a word that everyone who thinks about stuff—even in a fairly straightforward commonsense way—should be familiar with. Why? Because metaphysics refers to your understanding of reality. Consider the following questions: What do you think the world is made of? Why is the world the way it is? What is our (human) place in the world? If you think about these kinds of questions at all, you are (at least) a novice “metaphysician” and you have a “metaphysical” view of the world. (Note that “world” here refers to everything that exists).

What about the Enlightenment Gap? What is that? Before I define that, let’s start with the Enlightenment. The Enlightenment is the age that valued the power of reason (and for some, the power of reason over faith). It was an age in which leading intellectuals argued that we could understand the natural world using logic, math, and the scientific method. Although the Enlightenment is often formally dated to begin 1715, the roots of it date back further. Certainly the work of early scientists/natural philosophers like Galileo (1564-1642) and Descartes (1569-1650) laid key parts of the foundation.

Some argue that the Enlightenment should be dated to the publication of Isaac Newton’s (1642-1726) “Principia” (Mathematical Principles of Natural Philosophy) in 1687, which is the single most important scientific publication in history. What did Isaac Newton do in Principia? He developed a mathematical framework that described matter in motion (this is sometimes called "classical mechanics"). He did this so well and so completely that he basically offered a mathematical theory of matter that was the foundation of our understanding that lasted almost 225 years, until the development of modern physics (which involved the development of general relativity and quantum mechanics and took place between 1900-1930).

So the Enlightenment is the Age of Reason and is the beginning of the modern age, when folks started to see the full power and possibility of a scientific understanding of the world. What, then, is the Enlightenment Gap?

The Enlightenment Gap is what I use to refers to “space in between” the tensions and contradictions between the worldviews of Christianity on the one hand, and the picture of matter in motion that emerged via Newton’s physics on the other. Let’s tie this back to the term metaphysics. The Christian perspective had one metaphysical worldview and the new physical science perspective had another. Let’s spell them out in terms of: 1) What they say the world is made of; 2) Why the world is the way it is; 3) What is the place of the human in the world. (I am indebted to Peter Van Inwagen’s Metaphysics for this framing of the issues).

The 19th Century Christian Metaphysical Worldview

1. The World consists of God and all that He made. Everything exists because of God and exists because God chose it to exist. God created both the material world of things and the spiritual world of the soul.

2. God has always existed and He has to exist because the world exists and the logic of the world exists because of God. In this sense, God exists in much the same way that 2 + 2 = 4 exists; it is a logical consequence of the world. Although God has to exist, all other things could have not existed if God chosen not to create them.

3. Human Beings were created by God to love and serve him forever. He infused in them the power of the spirit, which allows them to be connected to God, if they choose to embrace this calling. In the same way that the heart is designed to pump blood, human beings are meant to serve God and their lives are a testament to the extent to which they do so. The course of human history is nothing less than a record of the extent to which humans have chosen to do what they were made to do.

The Metaphysical Worldview of 19th Century Physics (What I call below an Atheistic Physicalism, see here for a modern version)

1. The World consists of matter in motion, and there is nothing but matter. Matter obeys strict laws and everything is determined by these laws.

2. Matter has always existed and can never be created or destroyed. Because matter has always existed, there is no reason for the World to be. It just is and always has been and always will be.

3. Human beings are complex arrangements of matter, and they exist because they just happen to be how matter is organized right now. Also, because all material things obey strict laws, there is no such thing as free will or the freedom to choose. Human lives have no meaning other than what they construct for themselves, and when they die they simply become different (inanimate) arrangements of matter.

Notice the huge differences between these worldviews. It is worth noting that people like Rene Descartes and Isaac Newton basically held both worldviews. They did so by believing in dualism, which is the idea that there are two fundamental domains in the world, that of matter and that of mind/spirit (see the first point of the Christian worldview). In this way both Descartes and Newton (who was a very religious man) believed more in the first metaphysical worldview than in the second, at least in so far as generating a complete description of the world and our place in it. However, by the time the Enlightenment was in full swing, a number of increasingly skeptical scholars emerged (e.g., David Hume, 1711-1776), and more and more intellectuals began to adopt the second worldview.

The Enlightenment intellectual Pierre-Simon Laplace (1749-1827) is a great example of an advocate of the physicalist worldview. He believed everything was completely determined by the laws of matter in motion. There is a famous (but apocryphal) incident in which Napoleon, upon hearing of Laplace’s strict determinism about how the world works, asked about the place and power of the Creator in determining events. Laplace famously answered that he “had no need for that hypothesis”.

Pierre-Simon Laplace
Source: wikicommons

Psychology’s Metaphysical Problem

Hopefully now you can see the deep and profound tensions between Christian metaphysics and atheistic physicalism. Think of the space between them as a gap. What does this have to do with psychology?

These were the two dominant worldviews that were operating when the science of psychology emerged. Thus, psychology gets started as a discipline when its founders must choose either the first or second worldview. Because it is defined as a science and the science of the time was the lawful determination of matter in motion, most (but not all) psychological scientists of the day adopted the second worldview, that of an atheistic physicalism. For example, Sigmund Freud’s psychoanalysis and John Watson’s behaviorism were both atheistic physicalist worldviews. Both assumed a classical, deterministic, matter-in-motion view of the universe, and believed that, at bottom, people were just complicated arrangements of matter.

So what is the problem? The problem is that NEITHER of these two worldviews is adequate for modern psychology. The reason the first is inadequate is the same reason that has been given since the Enlightenment. Science was founded on the assumption that the world is a natural and closed system and that is the only way scientific justifications systems can work. In other words, positing a theistic God that makes things happen violates the “language game” of natural science, and that is why God continues to be absent in science classes.

There are several reasons that the second worldview is now considered wrong, but I will list three major ones. First, energy now shares with matter “foundational status” in the sense that both energy and matter are fundamental in physics. Indeed, most physicists now would likely view energy as the more fundamental, if they had to choose. This changes the fundamental essence of the universe from an “object view” to a “process view” (see here for an elaboration of what this means).

Second, the developments in quantum mechanics in the early portion of the 20th Century blew up the strict deterministic picture that people like Laplace had of the universe. It is now largely understood that the fundamental character of the most basic elements of the universe (i.e., particles) has a random (or stochastic) character. That is, there are unknowable random variations that play a role in what happens in the future, which means that the kind of determinism that Laplace argued for is impossible.

Third, the rise of information science has provided a whole new perspective on causation. Rather than causation being purely mechanistic in terms of exchange of forces, there are many systems whose causal properties are described in terms of inputs, computational processes, and outputs. Cells, brains, human language, computers and so forth must be understood in the language of information processing, which is not reducible to the language of matter in motion.

Okay, let’s pause and review. The field of psychology emerged at a time in the mid to late 19th Century when there were two dominant worldviews. Because it strongly identified as a science, it largely adopted the second, atheistic physicalist worldview of the day. But developments in science and philosophy have changed our picture of the world.

This offers an explanation of why psychology has struggled so. There was no metaphysical worldview that was up to the task for providing psychologists with a conceptual definitional system that allowed them to clearly define and talk about their subject matter. And because of that, many different psychology’s with many different subject matters emerged, and the field has been confused at its core ever since.

Enter the Tree of Knowledge System

The above analysis suggests that what is needed is a new metaphysics for psychology. This is what I offer with the Tree of Knowledge System. The ToK System provides a new way to “carve nature at its joints”. Unlike the traditional matter in motion view, this view is consistent with modern science and it provides a way to think about mental and cultural phenomena in a way that is neither physically reductionistic nor does it require a supernatural spiritual dimension. In this way, it is quite different than both worldviews.

Source: Gregg Henriques

Here are the answers that the ToK System has for the key metaphysical questions of: 1) What is the world is made of?; 2) Why the world is the way it is?; 3) What is the place of the human in the world?

1. The universe is an unfolding wave of Energy-Information that can be described in behavioral terms of objects, fields and change and exists in four different dimensions of complexity, Matter, Life, Mind and Culture. These are separable dimensions of complexity because the behaviors that take place at the levels above Matter are mediated by systems of information processing, specifically, genetic (Life), neuronal (Mind) and linguistic (Culture).

2. The universe came into being 13.7 billion years ago. There was a “moment of creation” in which a chain reaction in the singularity that created a massive inflation and gave rise to the four fundamental forces (electromagnetic, strong, weak and gravity) and the elementary particles (bosons, quarks, leptons; see below). These forces and particles formed into atoms and galaxies. Because of differential concentrations of energy and matter, there has been a flow of energy across various sections of the universe and this has resulted in the emergence of different forms of complexity. Energy flow on the surface of planet earth resulted in the emergence of self-organizing, self-replicating systems that we call life.

Gregg Henriques
Source: Gregg Henriques

3. Human beings are a unique pattern of Energy-Information flow. First, they are a kind of animal, and in the animal kingdom there arose self-organizing process mediated by the nervous system, which gave rise to experiential consciousness. Humans then developed full, open language capacities, which resulted in them exhibiting unique behavior patterns and having unique capacities for self-reflective knowledge and for generating knowledge about the world (such as the metaphysical picture of the world offered by the ToK!).

How the ToK Solves the Metaphysical Problem of Psychology

When psychology emerged on the scene, the early psychologists did not have a metaphysical framework for talking clearly about what it was that they were studying. The absence of the necessary metaphysical frame gave rise to profound questions pertaining to whether psychology was about humans or animals, behavior or “the mind”, unconscious processes or self-conscious reflection, as well as thorny issues pertaining to free will and determinism. All of these problems arise out of a faulty and incomplete metaphysical picture of the world.

The ToK System offers psychologists a new metaphysical system from which to operate. In doing so, it solves the problem of how to define the science of psychology. For example, it states very clearly that the base of psychology corresponds to the Mind dimension of complexity. That means that psychology’s basic subject matter is the behavior of the animal as a whole, mediated by the nervous system.

Because there is a break between Mind and Culture, that means that humans, which connect to the Cultural dimension through language, operate on a different dimension of complexity. Thus, human psychology should be a separate sub-discipline from basic psychology.

For more on “the problem of psychology” and how the ToK System solves it, see here, here, here, here, and here. Here is a visual for the argument.

Gregg Henriques
Source: Gregg Henriques
Gregg Henriques
A ToK Taxonomy
Source: Gregg Henriques


Metaphysics is a highbrow term, but really it just refers to one’s version of reality. The version of reality that intellectuals had during the Enlightenment consisted of two very different pictures: one of a Christian worldview, and the other of an atheistic physicalism. Neither was up to the task of effectively providing psychologists with a definitional system for their objects of study. Because of this Enlightenment Gap, psychology never got off on the right footing conceptually and it has been fragmented ever since. The ToK System offers a totally new metaphysical system for understanding the world and our place in it. It can solve the problem of psychology and assimilate and integrate the key insights from various perspectives to offer a coherent picture of the whole.

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