When Scientific Method Became a Metaphysical Dogma

One of the things I have become increasingly interested in is how scientific materialism became so dominant in the twentieth century that many people eventually stopped distinguishing between science and materialism. Science is a method for investigating the natural world. Materialism, or what today is more commonly called physicalism, is a philosophical position claiming that physical reality is ultimately all there is. Those are not the same thing. Yet during much of the twentieth century they became so closely associated that questioning materialism could make someone appear to be questioning science itself. I think we need to understand the historical environment in which this happened.

Scientific materialism did not suddenly appear in the twentieth century. Its roots extend through the Enlightenment, the Scientific Revolution, nineteenth-century positivism, Darwinian evolution, and the enormous success of physics, chemistry, biology, and medicine. But ideas do not develop in a cultural vacuum. European science arose within a civilization dominated for centuries by Christianity, while Judaism and Islam were also part of the broader Abrahamic intellectual world. By the nineteenth and early twentieth centuries, science was increasingly challenging explanations of nature that had traditionally been grounded in scripture, ecclesiastical authority, miracles, divine intervention, and supernatural causation. It is therefore hardly surprising that some advocates of science defined their worldview partly in opposition to religion.

Consider Marx, Engels, and Nietzsche. Marx came from Jewish ancestry but was baptized into Lutheran Christianity as a child. Engels grew up in a strongly Protestant family. Nietzsche was the son of a Lutheran pastor. All three eventually became powerful critics of traditional religion, although their philosophies differed enormously. Marx and Engels developed a materialist interpretation of history, while Nietzsche attacked Christianity from an entirely different direction. Their rejection of religion does not demonstrate that materialism was merely psychological rebellion. Nevertheless, it reminds us that modern European materialism developed in continual conversation and conflict with Christianity.

The pattern continued into the twentieth century. Bertrand Russell became one of the most influential critics of Christianity and defenders of a scientific outlook. A. J. Ayer helped popularize logical positivism, which treated many traditional metaphysical and theological statements as meaningless because they could not be empirically verified. B. F. Skinner's behaviorism attempted to explain human behavior without requiring an immaterial soul or even the traditional conception of an interior mind. Francis Crick eventually approached consciousness as something that should be explained through the physical brain. Daniel Dennett became one of the strongest philosophical defenders of a naturalistic understanding of consciousness, while Richard Dawkins later brought a similarly naturalistic interpretation of evolution into popular culture. Several of these thinkers had been exposed to Christianity as children and subsequently rejected it.

But there was another cultural force developing alongside this rejection of traditional religion that I think deserves more attention. The late nineteenth and early twentieth centuries witnessed an extraordinary fascination with Spiritualism, séances, mediums, spirit communication, psychical phenomena, occult societies, Theosophy, and esoteric teachings. Helena Blavatsky and the Theosophical Society became enormously influential. Spiritualist mediums claimed communication with the dead. Psychical researchers investigated telepathy and survival after death. Later figures such as Aleister Crowley became associated with ceremonial magic and occult experimentation. To a scientific establishment struggling to establish rigorous standards of evidence, this environment presented a serious problem.

Some scientists did investigate these phenomena. William Crookes, Alfred Russel Wallace, Oliver Lodge and others were willing to consider evidence that consciousness might not fit comfortably within a strictly materialistic framework. The Society for Psychical Research was created precisely because serious investigators believed extraordinary claims should be studied rather than automatically accepted or dismissed. Unfortunately, the world of mediumship also contained fraud, exaggerated claims, theatrical effects and sometimes outright deception. Scientists therefore had perfectly legitimate reasons to demand rigorous evidence.

My concern is that a reasonable skepticism sometimes hardened into something more philosophical. Instead of saying, “We have insufficient evidence for this particular claim,” the intellectual culture increasingly moved toward, “These things cannot happen because reality is physical.” That is a very different statement. The first is methodological skepticism. The second is metaphysics.

This distinction between methodological naturalism and metaphysical physicalism is extremely important. Methodological naturalism simply says that science should search for natural, testable, repeatable explanations. It has been spectacularly successful. We do not need to invoke spirits to explain lightning, infection, planetary motion or thousands of other phenomena once attributed to supernatural causes. But metaphysical physicalism goes considerably further. It says that because naturalistic scientific methods work so well, ultimately nothing exists except the physical. That conclusion is philosophical rather than something demonstrated by the scientific method itself.

I suspect that some of the hardcore physicalist dogmatism we still encounter today is partly an inheritance from this historical struggle. Science had to distinguish itself from ecclesiastical authority on one side and from séances, fraudulent mediums, occultism and extravagant metaphysical claims on the other. Drawing a hard boundary around physical explanation was enormously useful. But boundaries created for methodological reasons can eventually become unquestioned metaphysical assumptions.

We can also see the effects of this boundary policing in the treatment of respected scientists and scholars who ventured too far outside the accepted materialist framework. Harvard psychiatrist John E. Mack provides a striking example. Mack was a Pulitzer Prize-winning psychiatrist and professor at Harvard Medical School who became interested in people reporting extraordinary experiences commonly described as alien abductions. He did not simply declare that extraterrestrials were visiting Earth. He took the experiences and the people reporting them seriously and became willing to consider explanations that challenged conventional assumptions about consciousness and reality. Harvard investigated his work, an extraordinary development for a tenured professor, although ultimately his academic freedom was affirmed. Whatever we think about Mack's conclusions, his case demonstrates how professionally dangerous certain questions can become.

Rupert Sheldrake provides another example. Sheldrake was trained at Cambridge and worked as a biochemist and plant physiologist before proposing his controversial theory of morphic resonance and later investigating telepathy, animal behavior and other anomalous phenomena. His ideas have been heavily criticized by mainstream scientists, and criticism is certainly appropriate when extraordinary claims are made. But Sheldrake has also frequently been treated not simply as someone whose hypotheses may be wrong, but as someone whose questions themselves lie beyond respectable scientific inquiry. That distinction matters. Science advances by testing hypotheses, not by declaring beforehand which categories of phenomena reality is permitted to contain.

There are other examples. Nobel laureate Brian Josephson has endured considerable criticism for his interest in parapsychology and consciousness. Dean Radin, trained in electrical engineering and psychology, has spent decades conducting experimental research into psi phenomena while working largely outside mainstream academic science. Psychiatrist Ian Stevenson at the University of Virginia devoted much of his career to investigating children who reported memories of previous lives. His successor, psychiatrist Jim Tucker, has continued that research. Even earlier figures such as Alfred Russel Wallace, co-discoverer with Darwin of natural selection, and physicist William Crookes risked scientific ridicule because they took Spiritualism and psychical phenomena seriously.

None of this means Mack was correct about anomalous experiences, Sheldrake has demonstrated morphic resonance, Stevenson proved reincarnation, or parapsychology has established the existence of psi. That would simply replace one dogmatism with another. My point is different. If physicalism becomes an assumption about what reality is allowed to be, evidence that does not fit the assumption can be dismissed before it receives serious consideration. There is a tremendous difference between saying, “The evidence for this phenomenon is inadequate,” and saying, “This phenomenon cannot exist because our worldview has already determined what reality consists of.”

This is where scientific skepticism can quietly become philosophical dogma. The appropriate scientific response to an extraordinary claim is neither belief nor ridicule. It is investigation. Some anomalous claims will undoubtedly collapse under careful examination, just as fraudulent mediums were exposed a century ago. Others may remain unexplained, and some may eventually require us to expand our understanding of consciousness and nature. We cannot know which is which if certain questions become professionally untouchable. The great irony would be if a scientific culture that liberated us from religious dogmatism eventually created metaphysical boundaries of its own.

This is why I find the present debate over consciousness so fascinating. We are no longer limited to choosing between biblical supernaturalism and nineteenth-century materialism. Idealism, panpsychism, neutral monism, process philosophy and other approaches are again being seriously discussed. None of this proves Theosophy, validates Crowley, establishes mediumship, or demonstrates the existence of a spiritual dimension. Those questions must stand or fall according to their own evidence and philosophical coherence. But neither should the failures of fraudulent mediums or the inadequacies of traditional religious explanations be treated as evidence that consciousness must ultimately be reducible to matter.

Perhaps materialism performed an important historical service. It forced religion, metaphysics and claims of paranormal experience to confront evidence and intellectual accountability. But successful rebellion against one worldview does not automatically make the opposing worldview ultimately true. The pendulum may simply have swung too far. What began as the entirely reasonable scientific determination not to invoke invisible causes unnecessarily sometimes hardened into the philosophical conviction that invisible or nonphysical dimensions of reality cannot exist.

That is the distinction I believe we need to recover. Science should remain skeptical, rigorous and evidence-based. But genuine skepticism must work in both directions. We should be skeptical of unsupported spiritual claims, but we should also be skeptical of the unsupported metaphysical claim that physical reality is all that exists. Once we make that distinction, the question of consciousness becomes open again—not as a retreat into superstition, but as one of the most profound unanswered questions concerning the nature of reality.