Judging from the popularity of anti-religious polemics by authors like Christopher Hitchens, Sam Harris, and Richard Dawkins, evangelical atheism is making a comeback. Books in this genre make the same argument again and again: religious beliefs are unscientific and therefore irrational, and, since irrationality is dangerous, religion should be discarded.

Though they may not state it explicitly, their arguments rely on the value science places on falsifiability, or the potential for any given hypothesis to be falsified through experimental research. According to this principle, if there’s no experiment that could conceivably confirm or falsify a given hypothesis, then that hypothesis can’t be considered scientific. Many atheists argue that non-falsifiable hypotheses aren’t simply unscientific, but also irrational. By this reasoning, since the God hypothesis is non-falsifiable it should be abandoned.

A significant problem with this argument is that falsifiability has limited jurisdiction even within the sciences. As Carleton professor of physics and religious studies Ian Barbour writes in Myths, Models, and Paradigms (1974), "Discordant data do not always falsify a theory. One can never test an individual hypothesis conclusively in a 'crucial experiment'; for if a deduction is not confirmed experimentally, one cannot be sure which one, from among the many assumptions on which the deduction was based, was in error. A network of theories and observations is always tested together. Any particular hypothesis can be maintained by rejecting or adjusting other auxiliary hypotheses. . . . In practice the scientist works within the framework of accepted assumptions, and throws all the doubt on one new hypothesis at a time; but it might be just the accepted assumptions which should be questioned."

Barbour argues that science can be divided into four levels: (1) observations, (2) theories and theoretical models, (3) research traditions embodied in key examples or "exemplars", and (4) metaphysical assumptions about the nature of entities in the world such as atomic particles. The higher up the ladder you go, the less falsification operates as a self-correcting mechanism. When you reach the level of metaphysical assumptions—that is, the level that core religious beliefs typically operate on—falsification stops dead.

The question may then be asked: if metaphysical beliefs about such things as the existence of God are non-falsifiable, then why not dispense with them altogether? Those asking this question often ignore their own metaphysical position, which is typically a form of materialism. Materialism, which holds that matter—or at least mindless substance—is the basic stuff of existence, has significant problems of its own.

When it comes to the relationship between consciousness and matter, materialism is at a loss. If matter is the fundamental reality in the universe, then what is mind, or, more to the point, what is consciousness, and how does it interact with matter? Attempts by materialists to answer these questions have been notoriously unconvincing.

Consider, for example, epiphenomenalism, which holds that consciousness is an epiphenomenon of brain functioning incapable of exerting any causal influence on the brain’s workings. This perspective implies that it would be altogether possible for at least some fully functional human beings to have no consciousness whatsoever. Although they would act just like anybody else, these philosophical zombies would have no inner worlds. They would be complicated objects without any subjectivity whatsoever—just like the cosmos in its entirety is believed by materialists to resemble an infinitely complicated machine.

Materialism is challenged on a deeper level by modern physics. As Theodore Roszak writes in The Voice of the Earth: An Exploration of Ecopsychology (1992), “All discoveries in theoretical physics since the time of Planck, Curie, Bohr, Einstein, and Heisenberg have rendered the traditional concept of ‘matter’ meaningless. . . . All attempts to find some irreducibly simple ‘thing’ that will serve as the building block of all other more complex things have failed. There are no simple things, even at the subatomic level.”

Reality seems to be structured by mathematically discernible patterns, rather than by “matter,” however matter is defined. Whatever “mind” and “matter” are, they seem to be emergent expressions of these patterns. For example, the same fractal patterns that shape Norwegian fjords also guide the distribution and firing of neurons in our brain, and, according to physicist Mark Buchanan, the same mathematical power laws appear to govern the frequency and scale of earthquakes, forest fires, mass extinctions, wars, stock market fluctuations, and scientific revolutions.

In other words, since the distinction between “matter” and “mind” has lost its meaning, it makes as much sense to say that the universe is composed of mind as it is to say it’s composed of matter. This, in essence, is what theistic metaphysics is all about. Materialist and theistic metaphysics may well be limited but complementary languages for describing the same reality. When Homer Simpson said to his son, “What is mind? No matter. What is matter? Never mind,” he was, in this as in so many things, mistaken.

If the universe is in any way mind-like, then we have to ask whether it’s possible for us to perceive or commune with this underlying cosmic mentality. While any answer to this question is necessarily speculative, there is some evidence that our brains are organized in a way as to allow for these encounters to occur.

In Why God Won't Go Away: Brain Science and Belief (2001), Andrew Newberg, Eugene D'Aquii, and Vince Rause focus on the posterior superior parietal lobe, an area they refer to as the Orientation Association Area, or OAA. This is the part of the brain that distinguishes our body from its environment and allows us to navigate through the space around us.

Based on their research with experienced meditators, these authors believe that in deep meditation or prayer either the brain's quiescent or arousal system goes into overdrive, producing a corresponding activation of its counterpart—when pushed to its limit, the arousal system triggers the quiescent and vice-verse. As this happens, the brain enters a state known as de-afferentiation, in which the levels of sensory stimuli reaching the OAA suddenly fall. When this occurs, the OAA—which continues to function quite well despite the sudden loss of sensory input—produces an experience of infinite and ineffable oneness, interpreted either as pure egolessness or as immersion in a cosmic Other. If this state is achieved using methods that empty the mind of conscious thought through such practices as Zen meditation, then the experience will likely be one of egolessness. If, on the other hand, de-afferentiation follows intense focus on an image such as a holy symbol, then the experience will probably take the form of immersion in a cosmic Other. The authors emphasize that de-afferentiation isn’t pathological: it's not a seizure and it's not a psychotic episode.

De-afferentiation is remarkable in a number of ways, but most tellingly in how it's recalled later. When we dream or hallucinate, we're convinced that what we're experiencing is "real," but when we return to normal waking consciousness we can tell that what we experienced during these altered states was somehow less real than what we experience normally. In contrast, following a de-afferentiated state normal waking consciousness seems befuddled and unreal. Again and again, mystics claim that normal consciousness is like a waking dream in comparison with the lucidity of divine consciousness.

That this experience is produced by our brains doesn’t mean that it’s an illusion. After all, our capacities for mathematics and language are also generated by our brains. If the universe can reasonably be described as mind-like, then perhaps de-afferentiation is the means by which we transcend our perceptual filters and apprehend the divine ground of our being.

Joseph Campbell said that mythology uses poetic language to direct our attention to a realm of being that simply can’t be described in literal terms. De-afferentiation may be the brain state that provides direct access to this realm, which has gone by such names as the Godhead and Nirvana. If so, then besides having ample philosophical justification, theistic metaphysics would also be an appropriate expression of a remarkable faculty of the healthy human brain.

So read the evangelical atheists sceptically. To the extent that they criticize the literal interpretation of scripture and decry the ethical abuses committed in religion’s name, their work has merit and meaning. Once they go beyond this to attack theistic metaphysics for being unscientific and irrational, however, their critique fails, and they succumb to the same dogmatic foolishness they so readily condemn in others. When atheists like Hitchens and Harris then demonize and misrepresent religions such as Islam and then use this caricature to legitimize America’s imperial wars of aggression and the use of torture, evangelical atheism reveals itself to be just as bigoted as any other form of fundamentalism.