Fear and DNA

I

It is the great glory as it is also the great threat of science that everything which is in principle possible can be done if the intention to do it is sufficiently resolute. Scientists may exult in the glory, but in the middle of the twentieth century the reaction of ordinary people is more often to cower at the threat.

Everybody will doubtless be dismayed to learn that it is possible in principle—and technically not even very difficult—to transform human beings into two sub-peoples: the one moiety brainy and comparatively beautiful—like the Eloi of H.G. Wells’s famous journey into far future time—and the other moiety comparatively stupid but fitted by their docility and physical strength to do the dirty work and serve the others: Wells’s Morlocks or Wagner’s Nibelungen.

Why does not the mere possibility of this ultimate political prostration of mankind fill us with dismay? The reason is that the program I have just envisaged could have been embarked upon at any time in the past thousand years, merely by applying the most powerful of all forms of biological engineering—Darwinian selection—to a population—mankind—known by its open breeding system, lack of specialization, and rich resources of inborn diversity to be perfectly well able to respond to the empirical arts of the stockbreeder. The answer, in the form of a counter question, does something to explain why most biologists and laymen look rather coolly upon such attempts to curdie our blood: if these enormities have not been perpetrated or even seriously attempted hitherto by the comparatively straightforward and empirically well understood methods available for their execution, why should we now begin to fear that enormities as great or even greater will be executed by the much more costly and technically more difficult procedures of genetic engineering—by procedures which are conceptually well understood, to be sure, but are not yet anywhere near the level of proficiency in actual execution which the stockbreeder can command?

Nothing since the early days of atomic weaponry has caused so much dismay as the real or imagined threats associated with the development of genetical engineering and recombinant DNA research, the subjects of the books and papers under review.

At the root of all genetical engineering lies that which I described without qualification as the greatest scientific discovery of the twentieth century: that the chemical makeup of the compound deoxyribonucleic acid (DNA)—and in particular the order in which the four different nucleotides out of which it is assembled lie along the backbone of the molecule—encodes genetic information and is the material vehicle of the instructions by which one generation of organisms governs the development of the next. If the DNA message is altered, the effects of doing so are, in their context and of their kind, as far-reaching as the effects would be of altering the wording of congressional or parliamentary legislation or the wording of telegrams conveying diplomatic exchanges between nations. It is just such a process as this which in recent years has become possible by direct intervention—and to some degree at the experimenter’s will—a situation quite different from the action of natural or artificial selection upon naturally occurring differences in the DNA messages characteristic of different organisms. The first process changes the genetic makeup of an organism, the second, acting upon naturally occurring genetic differences between organisms, changes the makeup of a population of organisms.

Introducing what has become the most talked about version of the first process—“recombinant DNA”—June Goodfield comments, “Very simply, it is the new technology that enables a scientist to take DNA from one organism and splice it onto DNA from another to create something absolutely new: new living molecules, new genes, and therefore new life.”

The term “biological engineering” need not of course be confined to that part of it which takes the form of an attempted manipulation of DNA. “Engineering” embraces all that accompanies and makes possible the translation of thought into action, and even if “thought” is too far-fetched a description of the acts of mind that underlie some of its manifestations, “biological engineering” can certainly be extended to include suspension of life in the deep-freeze, the attempt to rear babies to term outside the body, and other enterprises upon which the Medawars¹ have not thought “idiotic” too harsh a judgment.

Francis Bacon described the goal of the New Science of the seventeenth century as “the effecting of all things possible.” The agents of this tremendous ambition were to be wise men and philosophers; he did not think there would ever come a time when people would do things merely because they were possible, yet that is exactly the mischief which the biochemist Erwin Chargaff, whom June Goodfield quotes, describes as the devil’s doctrine: what can be done, must be done. It must have been some recognition of this source of temptation in themselves or in their weaker brethren that led to the remarkable resolutions of the Asilomar Conference of February 1975 in California at which scientists themselves proposed that certain types of experimentation with DNA should be abstained from. No literary folk have ever done as much. On the contrary: any suggestion that an author should not write exactly as he pleases no matter what offense he causes or what damage he does is greeted by cries of dismay and warnings that any such action would inflict irreparable damage on the human spirit and stifle forevermore the creative afflatus. Let us count it a mercy that we don’t have to put up with this kind of talk from scientists; I mean, put up with the argument that the discovery of the truth is a complete justification for anything they may choose to do.

Although it was historically the most important, the Asilomar Conference of 1975 is not the only evidence of an awareness of possible evils acute enough to prompt scientists to accept guidance or impose upon themselves a censorship restricting their freedom to do exactly what they please. The National Institutes of Health have issued guidelines on the prosecution of recombinant DNA research and the British Medical Research Council has issued a cautionary document on genetic manipulation guided largely by the report of Lord Ashby’s Working Party on this subject.² The Federation of American Scientists has issued a thoughtful and gravely worded public interest report³ on the subject and the New York Academy of Sciences has devoted a symposium volume to a conference on the ethical and scientific problems raised by the human uses of molecular genetics.⁴ At this conference Daniel Callahan asked, “How, then, are we to possess power without being possessed by it?” adding that this was the fundamental question underlying the problem of ethical responsibility in science. Lord Acton and others have pointed out that the same is true of political action. Callahan is not one to blame the weapon for the crime and he says that “if the quest for scientific knowledge is to be condemned because some of that knowledge may be misused, then so must the quest for all knowledge.” Again, “there is no special responsibility applying to scientists that does not apply to others.”

There was this difference though: scientists were now more fully cognizant than ever before of the way in which innocent-seeming and intrinsically inoffensive experimentation may lead to disastrous consequences. It was therefore, Callahan said, a special obligation upon a scientist to envisage what consequences of his work were conceivable and to share these misgivings with his colleagues. I believe that it is just this attitude which underlies the present unease of biologists about what the consequences of molecular genetic engineering may be.

In his book Biohazard, Michael Rogers does not plunge us right into the middle of things but explains carefully and intelligibly the classical researches that provided the conceptual foundations of modern genetic engineering, making special mention of Archibald Garrod, who first identified the so-called “inborn errors of metabolism” that occur because the body has a missing or defective gene, and of the classical experimental researches of Beadle and Tatum on the bread mold Neurospora crassa showing the connection between the action of genes and that of enzymes. Garrod’s work and the Neurospora work represent some of the finest science of the twentieth century. From there he proceeds, justly and inevitably, to the dramatic and often recounted work on pneumonia bacteria by O.T. Avery and his colleagues in the Rockefeller Institute. These brilliant experiments first revealed that the genelike agent responsible for transforming certain bacteria from being non-lethal to lethal was none other than deoxyribonucleic acid—DNA for short—an abbreviation Rogers is sanguine enough to believe has now entered the vernacular. It is especially pleasing to see the prominence given to the name of a man, O.T. Avery, who deserves type as big and lights as bright as those of anyone who helped to tell the great story of DNA. Rogers, Wade, and Goodfield tell the same story of course: it is a good story and all three tell it well and in much the same way, though Goodfield’s aperçus are the most personal.

It will now be helpful to take evidence from a variety of different well-informed sources.

Nature, the world’s foremost scientific newspaper, has not stood aloof from the controversy. On the contrary, looking back over the “Recombinant DNA Debate Three Years On,”⁵ an editorial declares that:

…information generated during the past three years indicates that the potential hazards associated with gene-splicing experiments may be more remote than once believed. For example, a special meeting of scientists and health experts, convened by NIH earlier this month, concluded that there is virtually no chance that recombinant DNA experiments could touch off an uncontrollable epidemic.

Nature goes on to cite Dr. Roy Curtiss, a respected microbiologist from the University of Alabama, as having written after much experimentation with the laboratory strains of the bacillus E. Coli that are being used in genetic research:

I have gradually come to the realization that the introduction of foreign DNA into EK1 and EK2 host-vectors offers no danger whatsoever to any human being.

A more serious danger, maybe, is that the allegedly hazardous nature of the work may induce grant-giving agencies to impede the development of molecular biology or, more likely, to give molecular biologists seemingly valid reasons why their patrons should pull the purse strings together just when authentic supplicants are peering eagerly inside. A statesmanlike frown is accordingly directed by Nature at Senator Edward Kennedy’s health subcommittee which is engaged in devising restrictive legislation that could possibly impede worthwhile research.

The Federation of American Scientists has a long record of service to the community, and the article “Splitting Atoms and Transplanting Genes,” in its recent Public Interest Report, very properly reminds us of its stalwart services to the nation in making sure that the hazards of atomic energy became widely known. It now sees it as part of its function to do as much for recombinant DNA research, but far from holding up the profession to public obloquy, the FAS writes of it rather handsomely:

The researchers have behaved with unprecedented restraint and caution. Raising the issue themselves; bringing it to public attention; urging the voluntary deferral of various experiments; and debating the hazards in full public view, represents four quite different and thoroughly commendable steps. In addition, most have, quite surprisingly, been able to come to agreement on a set of guidelines that have grown steadily more stringent—even while many of the researchers have grown more sanguine about the dangers. This is a tribute to the statesmanship of their leaders. It is no surprise that now they want to go ahead with research which all observers agree is filled with promise, and which promises tremendous assistance in understanding biology. They only ask a “yellow” light—the right to proceed with caution.

Among the hazards the FAS calls attention to is the accidental escape of potentially dangerous organisms as yet unknown in nature. The FAS seems to fear that the body’s immunological system would be confounded by such unknown organisms. This fear of the unknown because it is unknown is not really justified. Human beings for example are perfectly capable of mounting immunological reactions against organisms new to them or even against chemical compounds which they have never met before—which, indeed, have not yet been invented. It is a misunderstanding of physiology to suppose that immunological-like neurological reactions depend at least in part on prior experience: there is after all always a first time we are confronted with any disease-causing organism but we do not necessarily succumb to it. The FAS goes on to say:

The basic current hazard is the introduction into bacteria of genes which make the bacteria more dangerous. In the simplest case, such genetic changes might give one strain of bacteria the resistance to antibiotics that exists in other strains; thus some such antibiotic as penicillin might suddenly find that strains of bacteria that cause pneumonia had become resistant to its application.

It is notorious, though, that this process has been going on since penicillin was first introduced into medical practice and used more frequently and in larger doses than immediate needs called for. The appearance of antibiotic resistant strains of formerly susceptible bacteria is a typical evolutionary process. Although the existence of penicillin-resistant strains of bacteria is a major nuisance, it does not portend widespread disaster: rather it puts biologists on their mettle to find ways around the problem.

The FAS draws special attention to and endorses the main conclusions of the Working Party under Lord Ashby of the benefits and possible risks of genetic engineering. The Working Party’s conclusions are worth setting out anew:

We now have to declare our assessment of the potential benefits and practical hazards of using the techniques we have described. We reiterate our unanimous view that the potential benefits are likely to be great. The most substantial (though unpredictable) benefit to be expected from the techniques is that they may lead to a rapid advance in our detailed understanding of gene action. This in turn might add substantially to our understanding of immunology, resistance to antibiotics, cancer, and other medically important subjects.

Furthermore, application of the techniques might enable agricultural scientists to extend the climatic range of crops and to equip plants to secure their nitrogen supply from the air. Another possible application is that segments of DNA, selected because they are templates for valuable products such as hormones, antigens or antibodies, might be produced in bulk by multiplying them in culture of E. coli: this would be of great benefit to medicine. And it is not inconceivable that the technique might ultimately lead to ways to cure some human diseases known to be due to genetic deficiency.

In discussing the hazards of these techniques we have to distinguish between the risk to workers in the laboratory and the risk to the public. Many scientists are engaged on potentially hazardous research (using radioactive materials, or unstable chemicals, or pathogens). They and those who work with them are trained to take precautions; accidents are rare and they do not spread. But if the danger is one which might not be contained within the laboratory, the need for precaution is much greater and the public have a right to seek assurances that they are not at risk.

Fortunately there are precedents for making such assurances. In the production of some vaccines, in public health and hospital laboratories, in research institutes for the study of infectious disease, it is essential to handle pathogenic organisms, some of them extremely dangerous. Accordingly, there is a well developed strategy of containment for these hazardous operations…. The dramatic response to any failure in containment illustrates how rare such failures are. A recent example of this is the enquiry which followed an outbreak of smallpox in London in 1973.

In short, the potential benefits of recombinant DNA research are great and the precautions the experiments call for must be commensurate with the magnitude of the risks involved.

I once had the pleasure of a lengthy formal discussion with the late Jacques Monod, at that time the Director of the Institut Pasteur, about a number of biological problems having to do with the threat and promise of genetical engineering—a subject upon which he was as well qualified as anybody in the world to express an authoritative opinion. We agreed that both the threats and the promises were greatly exaggerated and that the realization of both good and bad dreams was a very much more difficult exercise than it was commonly assumed to be, but at the same time Monod made an exception of cloning—the production of an indefinitely large number of replicas of some chosen human type.

Cloning was a definite possibility, he believed, as many others do too. The procedure has nothing to do with the recombinant DNA, however; it is biological engineering in the wider sense discussed above. To get it into perspective I should like to run over the procedure that would have to be adopted if cloning were to succeed. The first step would be to wash out from the fallopian tube a fertilized and therefore activated human egg—an egg developmentally ready to go. The egg would be stored in a cool, sterile nutrient medium outside the body and then manipulation could begin. If toads and newts are anything to go by, the egg’s own nucleus could be replaced by a nucleus from an ordinary body cell (a lymphocyte nucleus, mayhap) from the tissues of the individual chosen for indefinite replication. The egg would then be maintained under conditions which allowed it to undergo a number of successive cell divisions—a process almost exactly analogous to twinning as it may sometimes occur in vivo.

That would only be the beginning of it, however, because for each such daughter egg to develop into a human being it would be necessary to find a woman whose uterus had been prepared by hormones in such a way that the daughter egg transplanted into it would continue with cell division and eventually attach itself to the uterine wall—“implantation” is the technical word. The embryo might or might not go to term; if it did, it would necessarily have the same genetic makeup as the individual whose cell nucleus substituted for the nucleus of the original egg.

Anybody with any experience of experimental pathology—and the rival attraction of less exacting pursuits means that their number is getting less and less—knows that to carry through this program and to overcome all the misadventures that could so easily befall it would require a degree of organization that would make the mobilization and deployment of an army seem like running a Sunday school picnic. Even supposing a grant-giving agency composed mainly of wealthy simpletons could be found to support such a foolish enterprise, the very many misadventures known by all experimentalists to beset such a scheme would almost certainly prevent its being realized. We need not worry then about the difficulty of finding any one human being whose indefinite replication could be thought of with equanimity, for considered as a whole the enterprise is simply not on.

No appraisal of genetic engineering would be fair unless Erwin Chargaff were called upon. Chargaff was one of those who played a leading part in the discoveries that led to our modern understanding of DNA, and his part too, like Avery’s, is not as well known as it ought to be. In writing “On the Dangers of Genetic Meddling”⁶ Chargaff is very skeptical about the overflowing cornucopia of advances in medicine and human welfare which, it has been alleged, can grow out of the use of genesplicing techniques—benefactions thought to include the repair of human genetic defects (a procedure very far beyond our present competence). Of this project I have said:

It is mentioned in the same spirit as that in which a young biologist seeking funds to study the growth of sea cucumbers in a pleasant seaside resort urges his patrons to believe that such an investigation will throw a flood of light on the transformation from the normal to the malignant cell: it is a harmless form of window dressing that all grant-giving bodies understand and allow for.⁷

Chargaff declares that the genetic engineers are not nearly so proficient as they are given the credit for being about the splicing of eukaryotic DNA into DNA of microorganisms. (Eukaryotic DNA is the DNA of organisms, such as animals and higher plants, in which genetic material is marshaled and structurally organized in the form of chromosomes, the nucleic acid being combined with a basic protein to form a salt-like compound):

Most of the experimental results published so far in this field are actually quite unconvincing…. It appears that the recombination experiments in which a piece of animal DNA is incorporated into the DNA of a microbial plasmid are being performed without a full appreciation of what is going on.

Chargaff is skeptical of the long-term efficacy of orthodox containment procedures for the possible escape of pathogens, and he asks why molecular geneticists have chosen as the subject of their experiments an organism Escherichia coli, the colon bacillus, which has for so many millennia been living in a state of symbiosis with man. “The answer is that we know so much more about E. Coli than about anything else, including ourselves.” He is right: so much knowledge and know-how is vested in E. coli that there is little likelihood of its being supplanted as a subject of experiment. In any event, so the patrons of E. coli argue, the laboratory organism has now been so modified in the course of prolonged culture outside the body that it no longer qualifies to be considered a regular member of the flora in our gut.

Clifford Grobstein,⁸ well known for his sensible and temperate views, deplores the polarization of the recombinant DNA debate into an antithesis between “best-case” and “worst-case scenarios.” The worst-case scenario he envisages comprises: worldwide epidemics caused by newly created pathogens; the triggering of catastrophic ecological imbalances; the power to dominate and control the human spirit.

The last of these imagined dangers rather surprised me, for it seemed to me to be on all fours with H.G. Wells’s Eloi/Morlock bad dream referred to earlier. Certainly nothing much more horrible can be envisaged than a procedure which not only fills the mind of man with untruth and misconception but leads to an active resistance to new learning and to anything that might conduce to improvement. Yet here again the technology that puts these grim possibilities within our power has also been known for five thousand years or more: it is known as “education,” and it too has its brighter side, for whatever procedures may persuade us to approve evil can in principle also be used to make us reprobate evil and rejoice in and embrace the good.

Writing of the disquiet of the laity Grobstein makes it clear, though, that “the fear is not so much of any clear and present danger as it is of imagined future hazards.” Grobstein fears that physical containment and the associated safety precautions reveal something of a Maginot Line mentality, for what is needed is research that will evaluate these hazards precisely, so that we know where we stand and shall not find ourselves standing still.

James D. Watson is well known to have a somewhat messianic conception of his role in the great revolution of molecular genetics, and it was hardly to be expected that he would remain silent amid the clamor of discussion on recombinant DNA. He says that the Asilomar Conference made him uneasy, and he now declares:

I did not then, nor do I now, believe that all recombinant DNA research is necessarily totally safe. The future automatically entails risks and uncertainty, and no sane person rushes in directions where he anticipates harm to himself or others. Instead, we try to adjust our actions to the magnitude of risk. When no measurement is possible because we have never faced a particular situation before, we must not assume the worst. If we did, we would do nothing at all.⁹

I do not think Watson is being unduly sanguine and I specially applaud his choice of the word “sane.”

II

Having now taken evidence from various quarters we may turn to the three works specifically under review. Nowadays laymen need not be told that “Cry havoc!” attracts more attention than the nightwatchman’s reassuring “All’s well, all’s well.” Happily none of these three books is disfigured by sensationalism; however there is something a little breathy about them all. None of them is definitive or pretends to be: these are interim reports: a definitive treatise could only be written from a height which none of the three authors can command.

Goodfield, though, turns her lack of inside knowledge to advantage by describing how she apprenticed herself to a laboratory in which recombination experiments were taking place. I liked specially her delighted description of the winding out of the exquisitely beautiful DNA fibers on a glass rod after they had been precipitated from solution by the addition of alcohol. It is not an essential part of her narrative, of course, but I sympathize entirely with her wanting to bring it in because when I myself prepared DNA for immunological purposes I can remember cruelly boring my colleagues by calling upon them to witness the very process June Goodfield describes.

Nicholas Wade might say that this episode illustrates his contention that “gene splicing is so simple a technique that for most present purposes it requires only a few dollars worth of special materials, all commercially available, and access to a standard biological laboratory.” I think this is a misjudgment that reminds me of a prominent sociologist’s published contention (I shall not say where) that the manufacture of atomic bombs now lies within the abilities of a high-school student. It could equally well be said that appendectomy is a remarkably simple operation requiring no more facilities than are available in a quite ordinary hospital. But its execution requires a knowledge and know-how—the biological or surgical equivalent of worldly wisdom—which puts it for all practical purposes far beyond the reach of any ordinary villain or casual mischief-maker—a villain who collected appendixes as others collect stamps.

June Goodfield’s account has the merit of making it clear by implication why the conferment of antibiotic resistance is such a favorite exercise with genetical engineers. The reason is that it is not much good doing an experiment or modifying its procedure unless one knows whether the experiments work, or work better than before. When the conferment of antibiotic resistance is the transformation attempted, the organisms in which the transformation has been successful can be isolated very easily from a population that may be as diverse as the population of Times Square on a Saturday night (Goodfield’s image).

Each of these three books is good and since there is general agreement in the nature of the promises and the threats it would be idle to single out any one of them; for each has special merits. They agree, too, on the history of discoveries bearing on DNA, though Rogers goes back as far as Miescher in the 1870s—the man who first extracted the stuff long called nuclein from pus (one good mark, if we were having a competition). This historical excursion will certainly earn him the contempt of those semi-literates who regard any work done earlier than in the past year or two as of merely antiquarian interest.

Writing of safety precautions in laboratories handling potentially dangerous materials such as tumor viruses Wade quotes W. Emmett Barkley, the biological safety expert at the National Cancer Institute, in these terms:

“In the majority of labs we visit we see things that ought to be corrected. The greatest offenders are university labs, not industrial labs. Most people working with tumor viruses have been exposed to some extent.”

Barkley’s is the cry of safety officers throughout the world—in factories no less than in laboratories. I offer it gratis to some graduate actuary or sociologist on the lookout for a PhD degree that he should study the life expectancy of safety officers in factories and laboratories. I suspect they die prematurely of diseases of stress.

Incorrigible though their clients seem to be, however, we must keep it firmly in mind that for every steel worker who falls into the blast furnace, and every cider maker who dissolves, boots and all, in raw apple juice (rich in frighteningly powerful enzymes), hundreds and hundreds do not. The parallel is not facetious, because no one is more gravely and immediately at risk of the hazards to which they are believed to be about to expose the public than the people who actually carry out supposedly hazardous experiments. I don’t think the general public need take grave alarm until the inmates of institutions of genetic engineering themselves begin to fall by the way.

A further consideration that will influence the worldly wise is this: genetic engineers would very much like to confer upon microorganisms the ability to manufacture, in copious amounts, human insulin and the anti-viral agent called interferon, now being used in the treatment of some cancers.

When the engineers have demonstrated to everybody’s satisfaction that they can do on purpose what they very much want to do, then will be the time to reappraise very critically the dangers consequent upon their inadvertently doing what they do not want to do anyway.

The large-scale manufacture of either human insulin or interferon would be a very great benefaction to mankind, for the trouble with interferon at the moment—so often judged therapeutically disappointing—is that there isn’t enough to give it in dosages large enough for a clinical trial of adequate scale. Even penicillin did not finally triumph until it became possible to administer it in doses of the order of megaunits.

In Wade I came across for the first time the idea that nitrifying enzymes might conceivably be incorporated into plants that normally lack them, thus making it possible for them to capture from the atmosphere the nitrogen necessary for their growth and making them independent of added fertilizers (which are essentially compounds of nitrogen). The notion is not impossibly far fetched because some plants can be raised into whole organisms from single isolated cells. But here too I do very deeply sympathize with laymen and legislators who are trying to make sense of this whole strange farrago of pipe dreams and nightmares.

For their excess of fearfulness, laymen have only themselves to blame and their nightmares are a judgment upon them for a deep-seated scientific illiteracy which manifests itself in two ways.

In the first place the public deserve nothing but contempt for allowing themselves to be dupes of that form of science fiction which is our modern equivalent of the Gothic romances of Mary Shelley and Mrs. Ann Radcliffe; for being taken in, that is to say, by that trusty serio-comic character, the mad scientist, who to the accompaniment of peals of maniacal laughter cries out with a strong Central European accent, “Soon ze whole vorld vill be in my power.”

The second reason for their excess of fearfulness is this: that because imaginative writing is the only form of creative activity most people know, even educated laymen have no idea of the width of the gap between conception and execution in science. A writer who hits on a good idea—or even a composer who thinks of or, like Sullivan, overhears a good tune—can take up pencil and paper and write it down; he does not have to sue for bench space in a laboratory or send in five copies of an application explaining what his poem is going to be about, how many sheets of paper it will occupy, what imagery it is going to be clothed in, or how mankind will benefit by its completion. But when a scientist has an idea he has merely reached the beginning of a long haul which will certainly involve an appeal for funds which he may easily not get. He cannot simply walk into his laboratory with a purposeful and dedicated look on his face and execute the idea he has in mind.

The existence of this large gap means in effect that the execution of recombinant DNA research depends very largely upon political decisions. I do not use the word “political” in the sense that it would depend upon congressional or parliamentary legislation but simply in the sense that the project and the means of executing it depend on decisions that are not the scientist’s alone: they will depend at least in part upon peer judgment and on the policy decisions of an independent grant-giving body. But, it will be objected, many of those responsible for the decisions are themselves scientists; all right, but if one mad scientist is rare, a committee of scientists, all mad, is very much more improbable still. The existence of this very wide gap between conception and execution is that which allows the interposition of wiser counsels and restraining hands between the scientist’s idea whether bright or foolish and the possibility of its being put into effect.

So much then for the etiology and cultural history of the forebodings that cause so much disquiet among laymen. To the professional scientist these suspicions of his competence and probity are most disquieting. In one of a number of wise discourses on civilization Sir Kenneth Clark remarked that all great advances in civilization are based upon confidence. Although I have tried to explain it, I find it difficult to excuse the lack of confidence that otherwise quite sensible people have in the scientific profession, among whom sanity is much more widely diffused than seems to be generally realized. Scientists want to do good—and very often do. Short of abolishing the profession altogether no legislation can ever effectively be enforced that will seriously impede the scientists’ determination to come to a deeper understanding of the material world.