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Frank Visser, graduated as a psychologist of culture and religion, founded IntegralWorld in 1997. He worked as production manager for various publishing houses and as service manager for various internet companies and lives in Amsterdam. Books: Ken Wilber: Thought as Passion (SUNY, 2003), and The Corona Conspiracy: Combatting Disinformation about the Coronavirus (Kindle, 2020).

Parapsychology and the Persistence of the Paranormal

A Critical Assessment of Its Current Scientific Status

Frank Visser / ChatGPT

Introduction: The Science That Never Quite Arrives

Parapsychology occupies an unusual position in the history of modern science. For more than a century, researchers have attempted to establish whether human beings possess capacities that transcend the familiar boundaries of perception, cognition, and physical causation. Can people acquire information through telepathy? Can someone perceive a distant location without sensory contact? Can knowledge of the future precede the events that make that knowledge possible? Can mental intentions directly influence physical objects?

These questions are not inherently unscientific. If reliable evidence demonstrated that any of these phenomena occurred, the implications would be substantial. The problem is not that parapsychology asks extraordinary questions, but that its central claims have remained controversial despite decades of investigation. The field continues to produce experimental findings, statistical analyses, academic publications, and theoretical proposals, yet it has not achieved the kind of robust, independently reproducible evidence that would establish paranormal abilities as ordinary scientific phenomena.

The resulting situation is more complicated than either enthusiasts or dismissive skeptics sometimes acknowledge. It is too simple to claim that every parapsychological experiment has failed or that every positive result must be fraudulent. Equally, it is unwarranted to treat statistically significant experimental results as proof that telepathy, clairvoyance, precognition, or psychokinesis actually exist.

The central question is whether parapsychology has produced sufficiently reliable and distinctive evidence to justify its extraordinary interpretations. Its contemporary status depends on how carefully we distinguish experimental observations from the paranormal explanations attached to them.

What Is Parapsychology Trying to Establish?

Parapsychology traditionally investigates phenomena grouped under the label psi. These include extrasensory perception, or ESP, encompassing telepathy, clairvoyance, and precognition, as well as psychokinesis, the alleged capacity of mental activity to influence physical systems without ordinary physical interaction.

Other subjects sometimes associated with parapsychology include mediumship, apparitions, out-of-body experiences, near-death experiences, and reports of reincarnation. These topics overlap with psychology, neuroscience, anthropology, and the study of religious belief, but they do not all pose the same scientific question. An unusual subjective experience is not equivalent to evidence of an objectively paranormal event.

This distinction matters because the field can appear more successful when these diverse subjects are considered collectively. People undoubtedly have experiences that they interpret as paranormal. Some dreams seem to anticipate subsequent events; some coincidences feel extraordinarily meaningful; some individuals report vivid impressions of distant people or places. Such experiences are legitimate subjects for psychological investigation.

But the existence of an experience does not establish the truth of its interpretation. A person may genuinely experience a dream as precognitive without having obtained information from the future. A medium may sincerely believe that a deceased relative is communicating through them without the information actually originating from that relative. The scientific task is to determine which explanation best accounts for the observations, not to assume that the most extraordinary interpretation is correct.

Parapsychology becomes scientifically interesting when it moves beyond anecdote and attempts controlled experimentation. It becomes scientifically persuasive only when those experiments establish effects that withstand independent replication and rigorous attempts to identify alternative explanations.

A Century of Research Without a Decisive Breakthrough

Modern psychical research developed in the nineteenth century, partly in response to spiritualism and claims of communication with the dead. Early investigators attempted to distinguish genuine anomalies from fraud, misperception, suggestion, and wishful thinking. During the twentieth century, researchers increasingly adopted laboratory methods, statistical analysis, and controlled experiments.

J. B. Rhine's experiments with ESP at Duke University helped establish a more formal research program. Later researchers investigated sensory deprivation, altered states of consciousness, random-number generators, remote viewing, and the possibility of obtaining information about randomly selected future targets.

The Cold War gave some of this research an additional practical motivation. American intelligence agencies supported remote-viewing investigations because of concerns that adversaries might be exploring comparable techniques. The existence of government-funded programs subsequently became an important element in popular arguments for the reality of psychic phenomena.

Yet government interest is not scientific confirmation. Intelligence agencies investigate uncertain possibilities for strategic reasons, and an investigation's existence tells us nothing decisive about whether its underlying hypothesis is correct. The eventual operational usefulness of remote viewing must be assessed separately from the historical fact that it received funding.

The broader historical difficulty is that parapsychology has repeatedly generated reports of promising results without producing a stable body of findings that commands broad scientific agreement. Proposed effects have often been small, sensitive to experimental procedures, or difficult to reproduce consistently.

After such a long period of investigation, the absence of a decisive breakthrough deserves explanation. It does not logically prove that paranormal phenomena are impossible, but neither should it be treated as irrelevant. The longer an extraordinary claim remains elusive under controlled investigation, the stronger the case for demanding methodological transparency, independent confirmation, and clearly specified conditions under which the claim would be rejected.

The Ganzfeld Experiments: A Persistent Statistical Controversy

One of the best-known experimental approaches in contemporary parapsychology is the Ganzfeld procedure. Participants are placed in conditions of relatively uniform sensory stimulation, often involving diffuse light and white noise, while attempting to identify a target image or video selected for another person or transmitted through an experimental arrangement.

The rationale is that reducing ordinary sensory distractions may facilitate anomalous information acquisition. Researchers have published numerous Ganzfeld experiments and meta-analyses combining their results.

A 2024 version of a registered-report meta-analysis by Patrizio Tressoldi and Lance Storm examined more than four decades of Ganzfeld research, covering studies conducted between 1974 and 2020. The authors reported a small overall effect size, approximately 0.08, and argued that their analyses did not reveal convincing evidence that the result was explained by publication bias or questionable research practices. They concluded that the accumulated evidence supported the existence of anomalous perception under the experimental conditions studied.

This is a substantive argument, not something that can simply be dismissed by saying that paranormal research is nonsense. Meta-analyses can detect patterns too subtle to be apparent in individual experiments, and a small effect can be scientifically meaningful when it is reliable and reproducible.

Nevertheless, the interpretation remains disputed. A meta-analysis does not automatically transform a collection of imperfect experiments into a decisive demonstration of a new phenomenon. Its conclusions depend on the quality of the underlying studies, the comparability of their procedures, the handling of statistical choices, and the possibility of systematic biases that are not adequately captured by publication-bias tests.

The reported effect size also requires careful interpretation. An effect size of 0.08 is small. It does not mean that eight percent of participants possess telepathy, nor does it directly tell us how frequently a person could correctly identify a target in an ordinary setting. Its meaning depends on the particular statistical measure and experimental design.

The critical question is whether the effect survives prospective, preregistered, adequately powered experiments conducted by independent research teams that do not share the same theoretical commitments. If so, researchers would have stronger grounds for investigating its mechanism. If the effect diminishes or disappears under increasingly stringent conditions, that would point toward methodological or contextual explanations.

The Ganzfeld literature therefore represents a genuine dispute about experimental evidence, but it should not be presented as a settled scientific demonstration of telepathy. A statistical anomaly, even a persistent one, is the beginning of an explanation rather than its conclusion.

Replication: The Decisive Test

Replication is especially important in parapsychology because the claims being investigated are so consequential. If telepathy or precognition exists, carefully controlled experiments should eventually establish reproducible conditions under which the phenomena can be detected.

There is no requirement that every attempt must succeed. Many genuine scientific effects are difficult to measure, and experimental results can vary with context. But a successful research program must establish more than a collection of individually intriguing findings. It must demonstrate that independent investigators can obtain comparable results using procedures specified in advance.

Parapsychology has experimented with preregistration, registered reports, improved statistical methods, and greater transparency. These developments are welcome. Preregistration can reduce the temptation to select favorable outcomes after examining the data, while registered reports allow research questions and methods to be evaluated before results are known.

However, methodological reform is not itself evidence for psi. It is a way of determining whether the claimed effects survive more demanding tests.

The same applies to statistical sophistication. Bayesian analyses, meta-regressions, and elaborate models can clarify evidence, but they cannot compensate for inadequate experimental control or turn an ambiguous result into a uniquely paranormal one. A small deviation from chance can arise for many reasons, including random variation, unrecognized information leakage, analytical flexibility, and systematic experimental bias.

The strongest test would combine preregistered hypotheses, complete data reporting, independent laboratories, suitable controls, and successful direct replication. Researchers should also agree beforehand on what magnitude of effect would count as meaningful and what outcomes would count against the hypothesis.

After decades of research, this is not an unreasonable demand. It is precisely the standard required if parapsychology wishes to move from a contested research specialty into established science.

The Problem of Multiple Explanations

Suppose an experiment produces results significantly above chance. What has been established?

At minimum, the data may indicate that the observed outcomes differ from the predictions of a particular statistical model. Whether this difference reflects a genuine and reproducible effect requires further investigation. Even if it does, the result alone does not identify its cause.

Consider a participant who appears to identify a target image without ordinary sensory access. Possible explanations include unnoticed sensory cues, flaws in randomization, information leakage, subtle procedural differences, statistical artifacts, or an effect that has not yet been adequately explained. The paranormal interpretation is one candidate among these possibilities, not an automatic consequence of the result.

This is where parapsychology frequently encounters its most difficult conceptual problem. Researchers may infer that because ordinary explanations appear insufficient, an extraordinary explanation must be correct. But eliminating some known alternatives does not establish a particular alternative unless the remaining possibilities have been adequately constrained.

There is also an important distinction between ruling out a specific conventional explanation and demonstrating a violation of established physical principles. The first is a local experimental achievement; the second is a much broader theoretical claim.

The same reasoning applies to precognition. A participant's apparently successful prediction of a future random event might motivate further research, but it does not immediately establish backward causation or access to future information. The experimental procedure must exclude ordinary information leakage, selective reporting, analytical flexibility, and other sources of apparent success before such an interpretation becomes credible.

A rigorous parapsychology would welcome this distinction. It would not regard skepticism as an obstacle to discovery but as a means of narrowing the range of plausible explanations.

Remote Viewing and the Intelligence Connection

Remote viewing is the claimed ability to describe a distant or hidden location without ordinary sensory access. It became widely known through research associated with American government and intelligence programs during the Cold War.

The historical record establishes that remote viewing was investigated and that some experiments generated results their proponents considered promising. But the existence of a government program is often given more evidential weight than it deserves.

Intelligence research does not operate under the same conditions as a well-established scientific discipline. A technique may be explored because even a small chance of usefulness could have practical value. Investigations can continue despite uncertainty, and retrospective accounts can emphasize striking successes while giving less attention to failures or operational limitations.

The relevant question is not whether some descriptions appear impressive after the target is revealed. It is whether remote viewing can provide specific, accurate, and actionable information under blinded conditions at a level that exceeds chance and competing methods.

This requires predetermined scoring rules, protection against information leakage, complete reporting of unsuccessful trials, and independent evaluation. It also requires distinguishing the accuracy of a description from the usefulness of the intelligence it provides. A description may contain some correct details without identifying a target reliably enough to guide a real decision.

Remote viewing has not established itself as a dependable, independently validated intelligence capability. Its history illustrates a recurring pattern in paranormal research: intriguing experimental or anecdotal successes coexist with unresolved questions about reproducibility, specificity, and practical performance.

The appropriate conclusion is neither that government involvement proves the paranormal nor that every remote-viewing experiment was necessarily worthless. It is that historical interest and selected positive results fall short of decisive scientific validation.

Precognition: Can the Future Influence the Present?

Precognition is arguably the most radical claim in parapsychology because it challenges ordinary assumptions about the relationship between time, knowledge, and causation. Telepathy, if demonstrated, would raise questions about how information passes between minds. Precognition appears to raise an even more difficult question: how can information about an event be available before that event has occurred?

Laboratory studies have attempted to investigate this possibility using random stimuli, guessing tasks, and experiments in which participants' responses are recorded before a computer randomly selects or displays a target. Some researchers have reported small statistical effects that they interpret as evidence of anomalous anticipation.

The difficulty is that a statistically significant result does not establish that information has traveled backward in time. It establishes, at most, that the observations depart from the model used to predict them. The departure could be real without its cause being paranormal, and the experiment could require methodological revision before any causal conclusion is justified.

Researchers have proposed connections between precognition and quantum mechanics, retrocausality, or unconventional models of time. Such proposals may be intellectually interesting, but invoking quantum physics does not supply an experimental explanation. Quantum theory contains phenomena that challenge classical intuitions, yet this does not mean that human minds can routinely access future events. A physical theory that permits unusual mathematical descriptions of temporal processes does not automatically validate a particular psychic claim.

Precognition therefore illustrates a broader weakness in paranormal theorizing: the tendency to move too quickly from an unexplained observation to an expansive account of reality. The first task is to establish the observation independently. Only then does it become reasonable to ask what theoretical implications it might have.

Psychokinesis and the Limits of Mental Causation

Psychokinesis proposes that mental intentions can directly influence physical systems without the ordinary physical interactions required to produce such effects. Experiments have investigated whether participants can influence random-number generators, electronic devices, or other systems through intention alone.

As with ESP research, some studies and meta-analyses have reported small deviations from chance. Yet the central questions remain: Are the deviations reproducible? Are the experimental procedures sufficiently protected against bias? Do the findings survive independent scrutiny?

Psychokinesis faces an additional explanatory challenge. If mental intention can affect physical systems, researchers need to establish the conditions under which this occurs, the magnitude of the effect, and the limits of the proposed influence. Can the effect be reliably increased or suppressed? Does it depend on the participant, the target, or the experimental environment? Does it operate consistently enough to distinguish it from statistical noise?

Without such findings, psychokinesis remains difficult to incorporate into a coherent scientific account of physical causation.

The difficulty is not that science must reject any possibility of mind influencing matter. Ordinary mental activity already affects the physical world through bodily movement, speech, and behavior. The distinctive claim of psychokinesis is that it operates independently of those established pathways. That additional claim requires additional evidence.

The Case for Psi: What Defenders Actually Argue

A fair assessment must take seriously the arguments of researchers who believe the cumulative evidence for psi is stronger than its critics acknowledge.

In a widely discussed 2018 review in American Psychologist, Etzel Cardeña argued that experimental research provided cumulative support for parapsychological phenomena. He examined several research traditions and maintained that the evidence could not readily be dismissed by appeals to fraud, poor methodology, publication bias, or statistical incompetence alone.

Cardeña has continued to defend the scientific relevance of this research. In a 2025 discussion of psi and the mind-brain relationship, he argued that parapsychological findings deserve greater consideration in debates about consciousness, while acknowledging that their nature remains poorly understood.

These arguments should not be caricatured. Contemporary proponents are not necessarily relying on séances, spiritualist anecdotes, or uncritical belief in psychic powers. Some use conventional experimental methods, preregistration, meta-analysis, and statistical techniques familiar from other areas of psychology. Some are explicitly concerned with improving transparency and reproducibility.

Their strongest argument is that repeated small effects across multiple experiments might constitute cumulative evidence, even if no individual study provides decisive proof. They also point out that psychological research itself contains findings that are difficult to reproduce or whose effect sizes are modest. Parapsychology should not automatically be subjected to impossible standards that are never applied elsewhere.

There is force in the last point. Scientific standards should be consistent, and a claim should not be rejected merely because it is unpopular or theoretically inconvenient.

Nevertheless, the comparison with mainstream psychology has limits. A small effect involving a familiar psychological process does not carry the same theoretical implications as a small effect interpreted as evidence of information transfer without sensory contact or influence without ordinary physical interaction. The more extraordinary the interpretation, the more important it becomes to establish that the phenomenon is robust and that conventional alternatives have been excluded.

Nor does the cumulative argument settle the matter. Multiple studies can share methodological weaknesses, assumptions, research networks, or analytical practices. Combining their results may increase statistical precision without eliminating systematic error.

The crucial issue is therefore not whether proponents can point to positive studies. They can. It is whether the positive findings are sufficiently robust, independent, and specific to warrant the paranormal interpretation. That remains the central unresolved question.

The Skeptical Case: More Than a Refusal to Believe

Skepticism toward parapsychology is often portrayed by its defenders as a form of ideological resistance. According to this interpretation, mainstream science refuses to recognize psi because it threatens materialism, conventional physics, or established academic interests.

Institutional conservatism is real in science, and researchers can be influenced by theoretical commitments. But the existence of prejudice does not establish that the marginalized claim is true. Scientific consensus can be wrong, yet minority status is not evidence of scientific validity.

The skeptical case is strongest when it focuses on experimental performance rather than the presumed psychological motives of researchers. Its questions are straightforward: Can the effect be replicated? Are the data independently available? Were the hypotheses specified before analysis? Were unsuccessful results reported? Can alternative explanations be excluded? Does the effect yield reliable predictions?

Critics such as James Alcock have argued that parapsychology suffers from deep conceptual and methodological difficulties. In a 2020 article coauthored with Arthur Reber in American Psychologist, they challenged the positive assessment of psi evidence and argued that the field's claims conflict with well-established understandings of psychological and physical processes.

Their position is not that an extraordinary phenomenon must be rejected simply because it would require revising existing theories. Rather, they question whether the evidence is strong enough to justify such a revision in the first place.

That distinction is important. Science has repeatedly revised its understanding of nature, but successful revolutions did not rest solely on anomalies. They produced increasingly compelling evidence, coherent explanatory frameworks, and new ways to organize or predict observations.

Parapsychology has not yet achieved a comparable transformation. Its defenders may reasonably argue that the evidence deserves further examination, but they cannot treat the possibility of scientific conservatism as a substitute for demonstrating their claims.

Why the Scientific Establishment Remains Unconvinced

Parapsychology continues to occupy a marginal position within mainstream scientific institutions. It has specialist organizations, journals, conferences, and researchers, but it does not possess the broad institutional integration characteristic of established experimental disciplines.

The Parapsychological Association remains active, and its recent activities demonstrate that the field has not disappeared. Its publications and conferences continue to address psi, consciousness, anomalous experiences, and the methodological problems facing parapsychological research.

At the same time, the field faces difficulties beyond the familiar opposition between believers and skeptics. In his 2025 presidential address, Everton Maraldi of the Parapsychological Association examined institutional challenges and the need for greater internal criticism and integration. His discussion recognized that the field's problems cannot all be attributed to external hostility.

This is a significant point. A research community must be able to examine its own assumptions, disagreements, institutional incentives, and failures. If every criticism is attributed to prejudice, the discipline risks insulating itself against precisely the scrutiny that could strengthen its evidence.

Parapsychology also faces a problem of theoretical underdevelopment. Its principal categories describe alleged effects, but there is no generally accepted explanatory framework that integrates them into a predictive account. Telepathy, precognition, clairvoyance, and psychokinesis may be grouped together under psi, but their proposed mechanisms would appear to raise different problems.

What common process, if any, links them? What determines when an effect occurs? Why are the results generally small and inconsistent? What distinguishes successful from unsuccessful trials? Can the proposed phenomenon be manipulated systematically?

These are not peripheral questions. A scientific discipline becomes stronger when it progresses from detecting anomalies toward explaining them. Parapsychology has made methodological advances, but it has not produced a generally accepted theoretical breakthrough that resolves its central difficulties.

Its marginal status is therefore neither proof of persecution nor proof that every claim is false. It reflects a combination of contested evidence, unresolved explanatory problems, and the absence of a widely reproducible result that would compel the broader scientific community to change its position.

Does Psi Challenge Materialism?

Parapsychology frequently attracts interest because its claims appear to challenge a physicalist account of mind. If people can acquire information without sensory contact, or if intentions can influence physical systems without ordinary causal pathways, then some assumptions about the relationship between consciousness and the physical world would require reconsideration.

However, the argument often moves too quickly from alleged paranormal effects to metaphysical conclusions.

Even if a reproducible anomaly were established, it would not automatically prove that consciousness exists independently of the brain, that the universe is fundamentally mental, or that spiritual realities exist. Different interpretations might remain possible, and further evidence would be required to distinguish them.

Conversely, the current lack of decisive evidence for psi does not establish that every philosophical form of idealism, dualism, or nonreductive philosophy of mind is false. The metaphysical debate is broader than parapsychology.

This is especially important in discussions of survival after death. Mediumship, apparitions, near-death experiences, and purported memories of previous lives are sometimes invoked as evidence that consciousness survives bodily death. But these subjects require their own careful analysis. A vivid experience, an unusual memory, or an apparently accurate statement does not by itself demonstrate the continued existence of a disembodied mind.

Parapsychology cannot serve as a shortcut to metaphysical certainty. Its experimental claims must be assessed on their own merits before they can reasonably be used to support larger theories of consciousness or existence.

Paranormal Belief as a Psychological Phenomenon

There is another dimension to the subject that is considerably less controversial: paranormal belief and experience are themselves legitimate topics for scientific research.

People frequently report coincidences that seem meaningful, dreams that appear prophetic, intuitions that prove correct, or experiences of sensing the presence of someone who is absent or deceased. Such reports can illuminate how memory, expectation, emotion, perception, and belief interact.

Human memory is reconstructive rather than a perfect recording of events. People tend to remember apparent hits more readily than misses, reinterpret ambiguous experiences in light of subsequent events, and notice patterns in circumstances where chance can produce striking coincidences. Expectations can influence perception, while emotional significance can make an experience feel unusually compelling.

None of these observations means that every paranormal report can be explained by a single cognitive bias. Nor does a psychological explanation of an experience automatically settle every question about the external event associated with it.

But these mechanisms provide well-established reasons to investigate paranormal claims carefully. They also help explain why apparently extraordinary experiences can be common even if paranormal abilities have not been demonstrated.

There is an important distinction here between explaining why people believe something and establishing whether the belief is true. Both questions are scientifically legitimate, but they require different evidence.

A comprehensive psychology of the paranormal should investigate both the experiences themselves and the cognitive processes through which people interpret them. It need not presuppose that the experiences are supernatural, and it need not dismiss their subjective significance.

What Would Convincing Evidence Look Like?

The future of parapsychology depends less on producing additional extraordinary claims than on demonstrating that its central findings can survive increasingly stringent tests.

A persuasive research program would begin with clearly defined hypotheses and preregistered experimental procedures. It would report all relevant outcomes, make data and analysis methods available where possible, and permit independent researchers to examine the results. Experiments would be sufficiently powered to distinguish meaningful effects from random variation, and the research community would agree on appropriate standards for evaluating success.

Most importantly, independent laboratories would need to reproduce the effects without relying on privileged access to particular participants, investigators, or experimental environments. If an effect depends on special conditions, those conditions should be specified clearly enough to test. If the effect cannot be reproduced, researchers should be prepared to revise their interpretation.

A robust finding would also need to demonstrate specificity. It would not be enough to show that some experimental results depart from chance. Researchers would need to establish that the departure is reliably associated with the proposed paranormal process rather than with unrecognized features of the experimental arrangement.

Finally, a successful research program should aim for explanatory progress. A reproducible anomaly would be an important discovery, but the next questions would concern its mechanism, boundaries, and implications. Theoretical proposals should generate predictions that distinguish them from rival explanations.

Such standards are not intended to make paranormal research impossible. They are intended to determine whether the phenomena under investigation are real, reproducible, and scientifically informative.

Conclusion: An Open Question Is Not a Positive Result

Parapsychology remains a contested research field rather than an established science of paranormal abilities. It has a history of laboratory investigation, a specialist research community, and a body of literature containing positive statistical findings. Some researchers argue that the cumulative evidence for psi is substantial and deserves more attention than it receives. Their claims warrant examination rather than automatic dismissal.

Yet the decisive scientific achievement remains elusive. Telepathy, clairvoyance, precognition, and psychokinesis have not been established through a body of robust, independently reproducible evidence sufficient to command broad scientific acceptance. The field's experimental results continue to raise questions about methodology, replication, alternative explanations, and the relationship between statistical anomalies and paranormal interpretations.

The correct conclusion is neither that parapsychology has conclusively disproved the conventional understanding of mind nor that every conceivable paranormal phenomenon has been demonstrated to be impossible. It is that the evidence has not yet justified the extraordinary conclusions its strongest advocates draw from it.

There is a difference between remaining open to a possibility and treating that possibility as an established fact. Scientific inquiry requires the former, but it cannot dispense with evidence in favor of the latter.

After more than a century of research, parapsychology deserves to be judged by the standards it invokes on its own behalf. If psi effects are genuine, rigorous experimentation should progressively clarify their existence, reliability, and conditions. If they fail to survive such tests, the field should be willing to reconsider its central assumptions.

The most productive future for parapsychology would therefore be neither uncritical belief nor reflexive dismissal, but a more demanding form of investigation. Its researchers should be encouraged to ask difficult questions, including whether the evidence supports their preferred interpretations, whether their findings can be independently reproduced, and what would persuade them that their hypotheses are wrong.

The ultimate test is not whether paranormal phenomena remain imaginable, fascinating, or culturally influential. It is whether they can be demonstrated reliably enough to become part of our established knowledge of the world. Until that happens, parapsychology remains an intriguing but unresolved scientific controversy, not a successful revolution in our understanding of consciousness.