Science in Christian Perspective



The Prayer Test
Department of History and Institute for Fluid Dynamics and Applied Mathematics
University of Maryland
College Park, Maryland 20742

From: JASA 28 (March 1976): 11-14.
Reprinted from
American Scientist 62, No. 5, 561-563 ( 1974) and 63, No. 1, 6-7 (1975)

The early 1870s were good years for science. Not spectacular years, like 1543 or 1905, when revolutionary theories were published, but a time when scientists could proudly observe the consolidation of major achievements of preceding decades. James Clerk Maxwell's Treatise on Electricity and Magnetism (1873) provided an impressive synthesis of the discoveries and concepts of Oersted, Ampere, Faraday, and Kelvin, capped by his own interpretation of the physical nature of light and the prediction that electromagnetic waves could exist at any frequency. The molecular-kinetic theory of matter, founded on the ideas which Clausius and Maxwell developed around 1860, was cast into powerful and useful forms in major works of Ludwig Boltzmann (1872) and Johannes Diderik van der Waals (1873). And the biological sciences had at last found a persuasive explanatory scheme: Charles Darwin's Descent of Man (1871) provided the inevitable application of his theory of evolution by natural selection to the crucial problem of bow the human body and mind have developed to their present state. Before the end of the decade Boltzmann' was to predict that the nineteenth would be known as "Darwin's Century."'

The self-confidence furnished by such triumphs prompted a few Victorian scientists to issue a bold challenge. To those religious persons who believed in the effectiveness of prayer, they proposed a crucial experiment: let us see if the prayers of an entire country, directed toward a single desired outcome, can yield a measurable effect. Thus began the "prayer-test" debate of 1872-73, a remarkable but long-forgotten skirmish in the centuries-old warfare between science and religion.2

The Debate Begins

The first shot was fired by John Tyndall, known in scientific circles for his researches on radiant heat and acoustics, and to a larger public as an exponent of "scientific materialism," the view that all natural phenomena can eventually be explained by the laws of physics and chemistry. Tyndall sent to the Contemporary Review, with his own brief note of introduction, an anonymous article later attributed to a London surgeon, Sir Henry Thompson. As Tyndall said, the ostensible purpose of the article, entitled "The 'Prayer for the Sick,' " was "to confer quantitative precision on the action of the supernatural in Nature." He made little attempt to conceal his hope that the clerics who claim "the habitual intrusion of supernatural power in answer to the petitions of men" could now be made to put up or shut up.

The author of "The 'Prayer for the Sick"' asserted that if we are "in contact with a source of power available for human ends (or affirmed to be so on high authority)" we have a duty "to estimate its value." The reader will recall that quantitative determination of the energy-value of the various forces of nature bad been a fruitful scientific activity since the experiments of James Prescott joule and others in the 1840s.

Of the several purposes for which prayer is recommended, the gentleman continued, there is one whose consequences can now be objectively evaluated-the prayer that particular persons recover from sickness. Why should we not test the efficacy of prayer in the same way we test that of any other proposed remedy for a disease: select a group of patients suffering from the disease, administer the remedy in carefully measured amounts, and observe the effects. The crucial feature of any such test is not only that we have accumulated evidence on what happens to patients who have been treated with this remedy, but that we set up a "control group" of patients suffering from the disease, this group being as similar as possible to the experimental group in all respects and subjected to exactly the same conditions for the same period of time, except that it is not given the remedy being tested.

The test, then, would be to designate a particular hospital containing patients with diseases whose mortality rates are well established by past experience and to recommend that these patients be made "the object of special prayer by the whole body of the faithful" for a period of not less than three to five years. At the end of this time, the mortality rates in this group would be compared with those in groups suffering from the same diseases in other hospitals "similarly well managed." Those who really believe that they are not wasting their time praying to God should welcome such an opportunity of "demonstrating to the faithless an imperishable record of the real power of prayer."

That was certainly not the response of the representatives of organized religion who published their comments on the proposed test in the following months.

An editorial writer for the Spectator called it "revolting to the spirit of Christian prayer" and professed to approach the subject only with "reluctance and disgust." As it turned out, he could not resist the opportunity to flail the "arrogant physicists" for their contempt of religion. The editorialist pointed out that God is hardly likely to cooperate in an experiment whose real purpose is not to heal the sick but to provide a "scientific" measure of His power. In fact the biblical admonition "Thou shall not tempt the Lord thy God" would seem to be designed specifically for this situation-Tyndall's anonymous friend being thus cast in the role of the Devil.

The Reverend Richard Frederick Littledale, in an article on "The Rationale of Prayer" published in the Contemporary Review, promised to discuss the prayertest but instead devoted most of his space to a lengthy attack on Tyndall's "crusade against prayer," conducted in earlier speeches and articles. He went on to denounce the whole tribe of physicists who "seem unable to rise out of the plane of material conceptions into broad moral and spiritual views, or even to look at phenomena belonging to other spheres of knowledge with scientific eyes." The longevity of Christianity, and the persistence of the practice of prayer, are "facts" about the world which narrow-minded physicists choose to ignore, he complained.

But Reverend Littledale at last succumbed to the idea of a "scientific test" of the value of prayer. Instead of the one proposed by Tyndall's friend, he suggested that "a tabular comparison of the results severally attained by nurses who work for God"-such as the "sisters of conventual societies, who are moved by piety in their labor of love, and sustained in it by prayer"-and "nurses who work for money" should be made. There is no indication that such a test was ever made or that theologians' belief in the power of prayer would have been affected in any way by its outcome.

Reinforcement for the physicists soon arrived from another quarter. Francis Calton, already well known as the author of Hereditary Genius and English Men of Science, revealed that he had for several years been collecting statistical data on the efficacy of prayer. Tables of the average life span of various classes of persons show that kings and queens, who are usually the object of public prayer by their subjects, die earlier than lawyers, gentry, and military officers. Members of the clergy, presumably a prayerful class of men, do not live significantly longer than lawyers and physicians. Missionaries, whose effectiveness in spreading the gospel is crucially dependent on their living as long as possible after learning the language and habits of the country to which they are sent, frequently die shortly after arrival in spite of the many prayers that accompany them. The proportion of still-births suffered by praying and non-praying classes of parents appears to be identical, though there can be no doubt that if a person ever prays at all, it will certainly be for the health of an expected child.

Tyndall came out fighting at the beginning of the next round. He recalled some of the points on which religion had previously given way to science: the existence of the antipodes, the motion of the earth, the age of the world, and the theory of evolution. Abandoning belief in the physical value of prayer might well be the next "act of purification" by which religion would free itself from dependence on superstition, now that science had developed methods for analyzing forms of energy and could thus examine the claim that prayer "produces the precise effects caused, by physical energy in the ordinary course of things."

But Tyndall did not want to be accused of flatly denying the value of prayer, though no one was in much doubt as to his opinion. Instead he insisted that he was willing to admit "the theory that the system of nature is under the control of a Being who changes phenomena in compliance with the prayers of men" as a "perfectly legitimate" theory-provided that it was to be considered subject to experimental test like any theory in science. just as Newton's theory of light was abandoned when his prediction that light travels faster in water than in air turned out to be wrong, so the theologians should be willing to agree to a crucial experiment on the value of prayer and to abandon their theory if the result is unfavorable. Yet the theologians seem to resent the suggestion of such a test, either because they enjoy the very act of praying regardless of the results or because they are still under the sway of medieval mysticism.

The Controversy Spreads

James McCosh, a Scottish theologian who had gone to America to become president of Princeton College, now entered the battle. He criticized Tyndall for confusing the methods of the physical sciences with those appropriate to religion and moral philosophy and for misconstruing the type of "answer" God may give to prayers. The notion of a "control group" of sick persons, for whom one deliberately does not pray, is so repugnant to the true Christian as to cast doubt on the sanity of the enterprise. What if a skeptical young man, instructed by his father to be virtuous in order to enjoy ultimate happiness, were to propose an experiment with the boys of a poorhouse, 11 one-half of whom are allowed every indulgence, while the other half are exposed to restraint"? Would that be considered a reasonable "test" of moral philosophy, or would the father be justified in rejecting it with the assertion "that virtue is a thing binding on us, that by its very nature . . . is fitted to lead to happiness, and by pointing to the issues of virtue and vice seen in common life"?

As for the "effectiveness" of prayer, McCosh noted that there are many cases in which, as later becomes evident, it is the wisdom of God to answer the prayer by denying what the petitioner thinks he wants in order to lead him on to a better path. There are enough of these cases to show that one cannot simply tabulate the results of prayers as "answered" or "not answered." For example, McCosh continued, when Prince Albert was sick with a raging fever a few years ago, hundreds of thousands prayed for his recovery, apparently to no avail. Shortly after his death, Queen Victoria's advisers urged her to declare war on America. The Queen refused, however, "because her departed husband was always opposed to such a fratricidal proceeding." Yet one might suppose that if the Prince had been still alive his influence would not have been strong enough to stop the war. So in refusing to follow the wishes of those who prayed for Albert's recovery, God was really acting in their best interests. In the same way, for reasons we cannot now imagine, God might refuse to give preference to the patients in the ward being prayed for.

Of course it was just this kind of haggling about

The proposal of a "scientific" experiment to determine the power of prayer kindled a raging debate between Victorian men of science and theologians.

individual cases that Galton wanted to avoid when he proposed to treat the whole question statistically. Throughout the course of the debate, which continued in the Spectator and Contemporary Review for several months, hardly anyone attempted to refute his evidence, though other examples were brought forward in which the prayers of large numbers of people over long periods of time allegedly had been effective-for example, in promoting the spread of Christianity and the longevity of the Papacy. A more effective tactic was to admit that the primary purpose of prayer is not to request specific physical actions but rather to gain spiritual strength that may be employed in ways that have little to do with the subject of the prayer. This viewpoint would make Calton's statistics irrelevant and set aside the possibility of any kind of scientific test of the efficacy of prayer. Yet the theologians of the 1870s were reluctant to stick to this line; it would have looked too much like a retreat in the eyes of congregations accustomed to being urged to pray for specific acts of divine providence.

The scientists came out of this debate with their self-confidence intact, even though they do not seem to have deprived anyone of his faith in the value of prayer. The theologians effectively pressed the argument that religious beliefs cannot be tested by scientific experiment, though at some cost to their status in a century that was according increasing prestige to the scientific worldview. At least their position was more tenable than that of the spiritualists who did perform experiments on psychic phenomena but claimed that it was in the nature of these phenomena to disappear when a skeptical observer was in the room.

Perhaps the net effect of the debate was merely to widen the chasm between the scientific and religious viewpoints. No one pointed out that the "crucial experiment" is almost as rare in science as it is in religion. For example, contrary to Tyndall's statement, physicists had already abandoned Newton's theory of light for a combination of other reasons two decades before the experiment on the speed of light in water. One does not have to accept the extreme conclusion that some observers have drawn from Thomas Kuhn's theory of scientific revolutions-that changing from one scientific paradigm to another is like a religious conversion experience-to realize that Tyndall's view of the role of experiments in theory-testing is unrealistic. A scientist always interprets experimental data within some theoretical framework and necessarily hesitates to abandon that framework without compelling reasons going beyond the mere numerical discordance of a few observations. It is amusing to speculate on what Tyndall and Galton would have done if the test had been performed and had yielded positive results.

Conversely, people do change their religious beliefs, in part because of personal experience and observation, and such behavior is not qualitatively different from that of a scientist who changes his theory as he acquires new experimental data. The theologian who fears the spread of the scientific attitude is just as foolish as the scientist who denies the existence of dogmatism in scientific thought.

1Ludwig Boltzmann, 1886. Der zweite Hauptsatz der mechanischen Wdrmetheorie. Almanach der K. Akad. Wiss., Wien 36:225-59.

2The main sources for this debate are articles published in the Contemporary Review, July, August, and October 1872 and January and March 1873; a few brief notes on the subject also appeared in the Spectator and other periodicals during this period. Many of these articles are reprinted in The Prayer-Gauge Debate, by John 0. Means, Boston: Congregational Publishing Society, 1876. [See also Frank M. Turner, "Rainfall, Plagues, and the Prince of Wales: A Chapter in the Conflict of Religion and Science," The Journal at British Studies, 13:46-65 (May 1974).]

After the publication of my article on "The Prayer Test" (Am. Sci. 62: 561-63, Sept. 1974), two readers pointed out that the test was actually performed about ten years ago. I am grateful to Dr. Michael B. Shimkin (University of California School of Medicine at San Diego) and Dean B. G. Greenberg (University of North Carolina School of Public Health at Chapel Hill) for calling to my attention of the paper "The Objective Efficacy of Prayer: A Double-Blind Clinical Trial" (J. Chron. Dis. 18: 367-77, 1965) by C. R. B. Joyce and R. M. C. Welldon.

Joyce and Welldon studied the effects of prayer on patients "suffering from chronic stationary or progressively deteriorating psychological or rheumatic disease" using the experimental method proposed by 19thcentury scientists. They selected 38 patients matched in 19 pairs "as closely as possible for sex, age, and primary clinical diagnosis" and (in more than half of the pairs) for marital status and religious faith. One patient in each pair was prayed for, the other (as a "control") was not. The physicians who treated these patients were asked to evaluate their clinical state at the beginning and end of a trial period (from 8 to 18 months), not knowing which patient was being prayed for. The patients themselves were not aware of the experiment.

The results were somewhat inconclusive. Out of 12 pairs of patients for which it was definitely established that one patient did better than the other, the prayer for patient showed greater improvement in 7 cases, the control patient in 5. By itself this result is not statistically significant. But the sequence of individual results suggested that prayer helped patients whose clinical state was evaluated after a short time, while it hindered those who for various reasons were not evaluated until several months after the end of the original trial period. Since "it was not known" whether the prayer groups continued their efforts after this period, one does not know how to interpret the fact that in each of the first six pairs for which the evaluation was completed the prayed-for patient did better, while in five of the remaining six the control patient did better.

The Joyce-Welldon experiment did not settle the question of the efficacy of prayer but should stimulate further research.