Christian leaders often suggest the existence of immaterial concepts is evidence that a spiritual realm exists. Is this true? Consider an economic recession.
Economic recession: negative economic growth for at least two quarters.
Is an economic recession a spiritual entity? Few think so. Why not? There are two primary reasons.
An economic recession is not causally independent of the material substrate of people exchanging goods and services. The existence of an economic recession is wholly confined to the material realm, and is dependent on a material substrate. Even though a recession is itself immaterial, its existence emerges from and is inextricably tied to our physical reality. Spiritual entities are defined as independent, to some degree, from the causal matrix of our physical reality. For example, while the demons possessing first a man, then pigs in Matthew 8:31 evidently had to occupy a physical body, they were presumably spiritual entities that could violate normal physical laws.
An economic recession belongs to a theoretically infinite class of immaterial objects. Any type of pattern within an economy can be assigned a tag such as “recession” or “depression”. And these tags can be recursive. For example, we could denote an arbitrary level between a recession and a depression a “decession”, and, provided it offers communicative utility, it could be adopted by the language community as a legitimate concept. In contrast, you can presumably not generate new spiritual entities by simply abstracting them out of perceived patterns in our physical reality. The infinite set of abstracted concepts can be easily understood when considering the theoretically infinite number of possible immaterial games humans could invent such as poker, each with a theoretically infinite number of abstracted immaterial concepts such as “straight flush”. Consider the many other terms used in poker. We have “tilt”, “bleed”, “blaze”, “cow”, “brick” and “cripple” just to name a few. Do these concepts exist objectively as ontologically real “things” in some spiritual or supernatural realm? Or are they merely subjectively introduced terms? Did these “things” exist before poker existed? How many more of these “things” might exist? Suppose I am an avid poker player, and I find some significance in the relationship between a blaze and a brick, then call this relationship a “Xemph”. Is the concept Xemph suddenly an actual new entity in the supernatural realm posited by theists? Consider how many possible concepts might we might generate in this fashion. Because concepts of this sort can be just as recursive as language, there are as many possible concepts as there are possible sentences; an infinity. So there must exist an infinity of “things” in this unsubstantiated spiritual/supernatural realm promoted by theists should such a realm exist. But this is nonsensical. There is indeed an immaterial and subjective realm of concepts, but what is subjective is not objective by definition, and there has never been demonstrated to be a subjective concept that did not necessarily have an objective correlate in the substrate of the material wiring of a brain for example. What is immaterial is not spiritual, supernatural or independent of the material. It is a category error to equates the immaterial subjective realm with the spiritual/supernatural realm in which God is said to reside.
From this we can conclude there it is improper to suggest immaterial concepts demonstrate a spiritual realm.
Some Christian leaders have countered that correlation does not equal identity. This is true. It could be that the highly correlated relationship between the purchasing of goods and the notion of an economy is missing some essential spiritual force such as demons or angels we’ve so far failed to perceive. It could be that the immaterial notion of a bee colony requires hidden spiritual entities such as disembodied spirits. It could be that the apparent causal interaction of balls on a billiards table requires angels of some sort for that interaction. And it could be that the neuronal activity cognitive scientists have concluded is the substrate of the mind requires additional spiritual dynamics to fully explain its functions. However, for all of these phenomena, positing spiritual forces on top of the well-recognized physical forces appears quite superfluous and is not a rational conclusion.
We can see that the existence of immaterial concepts is not evidence of a spiritual realm in which discrete non-abstracted spiritual entities operate outside the constraints of physical laws. There is no need to lay a superflous spiritual realm over the physical realm to explain what we see in our reality. What some call a spiritual soul is explained quite sufficiently with immaterial concepts, concepts that are inexorably constrained by physical laws.
There is a strong and growing body of evidence demonstrating that lesions within the brain correspond to the absence of specific brain functions supernaturalists would like to attribute to a soul. In an attempt to counter this growing body of evidence for the non-spiritual nature of the human mind, some Christian leaders have introduced the analogy of a man chained inside his car. If the steering wheel is broken so that it only turns to the left, we can not conclude that there is no human operator inside the car. This is true. But consider another similar analogy. Google has recently tested driverless cars. Simply because a car maneuvers effectively around town does not mean there is an invisible human at the wheel. And the incremental removal of various mechanical components to test for any reduction in function is a successful scientific method of assessing causation. So it also is for the observations of cognitive scientists of decreases in mental functions after brain lesions. There is no need to invoke a soul as a cause, and doing so violates many well-established rules of scientific methodology. The fact that we have never observed a disembodied mind is non-trivial evidence such a mind does not and can not exist.
In summary, we can rationally conclude to a high degree of certainty that the mind does not merely operate upon the physical circuitry of the brain. The mind is the brain in the same way an economy is the totality of the relations between the relevant physical constituents. Just a a bee colony is an abstraction of the relations between individual bees, so also is the mind the abstraction of the functionality emergent of the activity of interconnected neurons.
To suggest that the operations of the immaterial mind is evidence for a spiritual realm is to not understand the process of abstraction, the infinity of abstractable entities, and the superfluity of adding unevidenced spiritual dynamics to what has already been adequately explained by physical dynamics.