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Retroactive prayer: a preposterous hypothesis?

BMJ 2003; 327 doi: (Published 18 December 2003) Cite this as: BMJ 2003;327:1465

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Responses to the Responders

Comments by Brian Olshansky and Larry Dossey
on the responses to:
Retroactive prayer: a preposterous hypothesis?

BMJ 2003;327:1465-1468

Were the control treated, as they should have been?
—J Martin Bland (19 December 2003)

Bland suggests that it was unethical in Leibovici’s study of
retroactive prayer to deny prayer to the control group following the
experiment. Some researchers in prayer experiments agree and have indeed
assigned prayer to the control group after completion of the study.
But can prayer be denied? Unlike an experiment involving the testing of a
pharmaceutical drug, it is unlikely that the control group in a prayer
study is totally denied prayer. Patients pray for themselves or their
loved ones pray for them, regardless of which group they are in. This
means that human studies test not prayer versus no prayer, but differing
degrees of prayer. This situation resembles high-dose versus low-dose drug
testing for a particular condition, which is frequently done. This
“problem of extraneous prayer” can be overcome by testing prayer not in
humans but in animals, plants, and microbes, or generators of random
numbers, all of which presumably do not pray for themselves.
Bland’s suggestion that the application of prayer to the control group
would have abolished the differences between the two groups if prayer is
effective is excellent and we support this idea in future studies. We
know of no studies that have employed this strategy.
— B. Olshansky & L. Dossey


1. Dossey L. The case for nonlocality. In: Reinventing Medicine.
San Francisco, Calif: HarperSanFrancisco; 1999: 37-84.

Does this mean that the holocaust never happened?
— Richard G Fiddian-Green (20 December 2003)

Fiddian-Green suggests that if prayer could retroactively influence
the hospital course of patients, the Holocaust and other events should be
equally amenable to being changed or rendered nonexistent. This assumes
that all events should demonstrate equal susceptibility to retroactive
influence. It is not obvious to us that this should be so. We do not
expect any antibiotic to be universally effective; penicillin is effective
against some microbes but not others.
The Holocaust is one of the most frequent examples cited by critics of
prayer. For all we know, without prayer the Holocaust might have been
exponentially more disastrous. One (fortunately) cannot perform controlled
trials of holocausts or natural disasters in order to put prayer to the
test. We believe that controlled clinical trials of intentionality and
prayer are more reliable guides to prayer’s effectiveness or lack of it
than examples such as the Holocaust.
— B. Olshansky & L. Dossey

Did anyone cite Pascal?
— Nicholas D Moore (20 December 2003)

Professor Moore states that one would expect, by chance, one in
twenty studies of prayer to be statistically positive. In fact, five of
nine controlled clinical trials of prayer have proved to be statistically
positive to date, far more than the one in twenty expected by chance.
References for most of these studies were cited in our paper.
Professor Moore sees connections between the justifications people make
for both homeopathy and prayer. We take no position on homeopathy and
leave it to others to decide if homeopathy and prayer are analogous.
Moore’s comments on the dangers of prayer are facetious, yet they should
be seriously considered. One of us (LD) has reviewed the negative aspects
or side-effects of distant intentions and prayer, for which there is
considerable evidence. For example, intentions have been employed
remotely to increase and decrease the kinetic rates of biochemical
reactions, microbial growth rates in test tubes, and the growth of tumors
in animals. These findings suggest paradoxically that so-called negative
prayers and intentions may have a benevolent aspect. For example, for
someone afflicted with tuberculosis or cancer, it would be quite wonderful
if prayers or intentions could demolish mycobacteria or cancer cells. The
capacity for negative prayers and intentions therefore constitutes
survival value for the organism possessing it, and is a rationale for the
development of such a trait from the perspective of evolutionary biology.
In view of the possibility that prayer might cause harm, informed consent
for prayer should be considered in medical settings. Not everyone wants
to be prayed for; some see prayer as an invasion of privacy and an attempt
to usurp personal control. There are situations, however, where informed
consent is impossible, as when the patient is an infant or is unconscious
and unaccompanied by next-of-kin.
— B. Olshanksy & L. Dossey


1. Dossey L. Be Careful What You Pray For. San Francisco, Calif:
HarperSanFrancisco; 1997

A preposterous hypothesis: retroactive prayer.
— Keith G Davies (20 December 2003)

We agree that a repeat of Leibovici’s study is warranted, including
prayer for the control group to see if the effect disappears.
— B. Olshanksy & L. Dossey

The power of thought in joules.
— Richard G Fiddian-Green (21 December 2003)

There are several reasons, as we stated in our paper, why energetic
concepts such as joules, drawn from classical physics, are inadequate in
understanding remote healing intentions and prayer. Nearly all the
evidence from experiments in distant intentionality and prayer suggest
that these phenomena are nonlocal — i.e., they do not decay with distance,
the distant correlations are immediate, they are unmediated by any
demonstrable physical or energetic intermediary signal, and the influence
cannot be shielded. Joule-related events do not behave like this.

It is unclear to most physicians how prayer could work if one
excludes exchanges of known forms of energy from its mechanism. This is
the essence of nonlocal events that have been documented in a variety of
studies within quantum physics over the past two decades. Several
hypotheses that make use of these findings have been advanced to explain
consciousness-related events that appear to be nonlocal. There is no
solid evidence so far, however, linking quantum physics and the operations
of consciousness. Whether quantum physics and nonlocality will eventually
prove fruitful in deciphering prayer and distant intentions remains to be
— B. Olshansky & L. Dossey


1. Clarke CJS. The nonlocality of mind. Journal of Consciousness
Studies. 1995; 2(3):231-40.

Theory of everything and multiple worlds: preposterous hypotheses?
— Richard G Fiddian-Green (22 December 2003)

Fiddian-Green’s suggestion that Leibovici’s findings are consistent
with the multiple-worlds hypothesis of Everett, Wheeler, and Graham
(sometimes called many-worlds or parallel-universe theory) is intriguing,
and we know of no way to disprove this possibility.
Although the multiple-worlds hypothesis is said to be mathematically
consistent, many physicists and cosmologists disdain it for the same
reason some individuals reject retroactive prayer: its seems inherently
implausible and therefore distasteful. Everyone to her own taste, we say.
We know of no explanation for retroactive prayer — or proactive prayer,
for that matter — that goes down sweetly.
— B. Olshansky & L. Dossey

If retroactive prayer changes outcome what of negative thoughts?
— Richard G Fiddian-Green (24 December 2003)

As mentioned above, considerable evidence suggests that intentions
can function remotely to bring about negative biological effects. Please
see our response to Nicholas D Moore, 20 December 2003.

Fiddian-Green asks whether it might be necessary to have
investigators with opposing beliefs perform randomized studies to
eliminate the possibility of biasing the randomization one way or the
other. This type of experiment has been performed by parapsychology
researchers Marilyn Schlitz and Richard Wiseman. Schlitz, who is cordial
to the possibility that conscious intentions can act remotely, was able to
effect statistically significant results in a laboratory experiment
involving the detection of being stared at, the details of which cannot be
described here. Wiseman, a widely known skeptic of these phenomena, was
unable to achieve significant results in the same experimental set-up.
The experiment was replicated by the same investigators.

Fiddian-Green also raises the question of whether hypnosis may help
explain some of the effects of acupuncture and whether the intentions of
the acupuncturist are involved by placing the needles “with conviction.”
We take this possibility seriously. Remote hypnotic suggestion was
attempted by many investigators with promising findings, before such a
phenomenon in the twentieth century came to be considered too implausible
to warrant further study.


1. Wiseman R, Schlitz M. Experimenter effects and the remote
detection of staring. Journal of Parapsychology. 1997;61:197-208.
2. Wiseman R, Schlitz M. Experimenter effects and the remote detection of
staring: an attempted replication. Proceedings of Presented Papers:
Parapsychological Association 42nd Annual Convention. 1999;471-479.
3. Dossey L. Hypnosis: a window into the soul of healing. Alt Ther
Health Med. 2000:6(2):12-17, 102-111.

Re: Re: retroactive prayer.
— Sandra Lobo (30 December 2003)

Lobo suggests that Leibovici’s study is “junk pseudoscience.” We are
well aware of the capacity of prayer research to evince passionate
responses. We believe, however, that the denunciation of prayer can be
justified only through further empirical studies and through an
examination of the already substantial data suggesting that consciousness
can act remotely in the world. As we stated in our paper, many phenomena
that were originally considered preposterous (the telegraph,
atherosclerosis as a cause of heart disease, and so on) are now accepted
in science. Several hundred additional examples could be cited. They
suggest caution in prematurely condemning phenomena that violate intuition
and shock common sense, however difficult this may be to achieve.


1. Cerf C, Navasky V. The Experts Speak: The Definitive
Compendium of Authoritative Misinformation. New York, NY: Villard; 1998.

Retroactive prayer: an important omission from the data?
— Norman Guthkeich (31 December 2003)

Guthkeich suggests that Leibovici’s subjects were not adequately
randomized. We also raised this possibility in our paper, and suggested
that the source of the inadequate randomization could have been
Leibovici’s own intentions. He may have unconsciously “randomized” the
long-stay cases into the control group, biasing the results toward his
preexisting intention. This possibility, we pointed out, is consistent
with studies suggesting that human intention can interfere with processes
believed to be inherently random.

Guthkeich states that the degree of energy required to accomplish
retroactive prayer is the equivalent of energetic output of all the stars
in our galaxy, an event that would surely have been noticed in a hospital.
But we do not know how prayer works. We have suggested above that it does
not involve energetic exchanges of the sort Guthkeich proposes, but is is
a genuinely nonlocal phenomenon — unmediated, unmitigated, and immediate.


1. Dossey L. How healing happens: exploring the nonlocal gap. Alt
Ther Health Med. 2002;8(2): 12-16, 103-110.

2. Dossey L. Energy talk. The Network. The Scientific and
Medical Network Review [UK]. April 1997; 63: 3-7.

3.Dossey L. The forces of healing: reflections on energy,
consciousness, and the beef Stroganoff principle. Alt Ther Health Med.

Re: Re: Re: Retroactive prayer
— L S Lewis (31 December 2003)

Dr Lewis’s recognition of the articles of faith that underlie his
assumptions is admirable. However, we are not as certain as he that the
past is off limits to the effects of human intention. As we stated in our
paper, the work of Schmidt and the review by Braud suggest that both
biological and non-biological systems can be affected by human intentions,
although the events in question appear to lie in the past.
These events are as mind-boggling to us as they are to Drs Lewis, Lobo,
and others who have joined this discussion. We find consolation in the
fact that they are also mind-bending to the physicists and researchers
involved. We are soothed by the observation of Sir Arthur Eddington about
the Uncertainty Principle in modern physics: “Something unknown is doing
we don’t know what.”


1. Eddington AS. Quoted in: Wilber K. Quantum Questions:
Mystical Writings of the World’s Great Physicists. Boston, Mass:
Shambhala Publications; 1984: back cover quotation.

Is Robert Hooke the real hero?
— Richard G Fiddian-Green (31 December 2003)
Who will rid me of this meddlesome priest? — Richard G Fiddian Green (3
January 2004)

We are dazzled by Fiddian-Green’s virtuoso command of English
history, of which we Americans are famously ignorant. To avoid displaying
this shortcoming, we thank him for his comments and reserve comment on the
intriguing connections he draws.

Retroactive prayer, etc.
—Norman Guthkeich (4 January 2004)

Guthkeich states, “The more fundamental problem is whether
petitionary prayer can ever be effective, since it must be addressed to A
Being….” We regard the mechanism — if that is the proper term — of
petitionary prayer as trans-empirical, beyond the reach of science as
presently constituted. We cannot imagine an experiment that could
decipher whether or not the Absolute, however termed, is involved in the
“prayer loop.”
This does not mean, however, that prayer is scientifically out of bounds.
Throughout history, people who believe in prayer have made the empirical
assertion that prayer is correlated with effects in the physical world.
Whenever empirical assertions are made, the attentions of science cannot
be ruled out. Science can tell us that something happened, even though
it may not tell us how.

Not all religions and cultures would agree with Guthkeich that
petitionary prayer necessarily involves a Supreme Being. For example,
some forms of Buddhism are not theistic, yet prayer is precious to such
Buddhists. They do not offer prayers to a god but to the universe at
large. In several of the clinical studies involving the remote effects of
prayer and intentionality, it does not appear to matter which religion the
intercessor is affiliated with or whether s/he is affiliated with a
religion at all.

These observations can be inflammatory to religious fundamentalists
who are convinced that their one true god would answer no prayers but
their own. Yet studies in intercessory prayer say otherwise. This is one
reason why these studies affirm religious tolerance, from which our world
could currently benefit.


1. Dossey L. The return of prayer. Alt Ther Health Med.
1997;3(6):10-17, 113-120.

Personal note

We are grateful for the thoughtful comments of the many responders to
our paper and the time they took to craft them.
— Brian Olshansky, MD
— Larry Dossey, MD
Response to responses, BMJ

Competing interests:
We are the authros of the manuscript responding to some of the comments

Competing interests: No competing interests

20 January 2004
Brian Olshansky
Professor of Medicine
Larry Dossey
University of Iowa, Iowa City IA 52242