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outside the uterus at 28 weeks. Some do not make a very good job of it at 34, 35 weeks, and some do at 24, 25.

To my knowledge, the earliest reasonably substantiated case of extrauterine survival was in a child just under 23 weeks. But obviously, this in turn is very much predicated by the life-support system available to that baby as soon as it is born.

Dr. LEJEUNE. Mr. Chairman, I am not a specialist on fetus, but I would like to stress a very simply analogy. A fetus inside this ambiotic thing is very comparative to a cosmonaut in a space capsule. Now, you send a cosmonaut to the moon and he has his catheter and he has a whole supply to survive. Now, if you opened this catheter, the cosmonaut on the moon would not live. But nobody would believe that this cosmonaut is not viable. It just means that he can live on the moon if you respect his space suit.

It is exactly the same thing with the human fetus. No matter how big it is, it will survive if you do not break his survival system. That he is viable from the very beginning under the normal conditions. Senator BAYH. Dr. Liley, you are with the support system.

Do you anticipate perfection in that support system that will move that age down from 34 weeks, where you say it has a pretty good chance, to 32, where there have been examples, on down to an earlier age, 22?

Dr. LILEY. I would be completely confident, Mr. Chairman. Just because we happen to be at the forefront of medical science in this field, we are certainly not arrogant enough to assume we are at the pinnacle of it.

Senator BAYH. Any question, gentlemen?

Thank you, gentlemen. I appreciate your being with us.

Our next panel will be comprised of Dr. Gerald M. Edelman, professor at Rockefeller University in New York; Dr. Norton Zinder, professor of genetics, Rockefeller University in New York; and Dr. John D. Biggers, professor of physiology, laboratory of human reproduction and reproductive biology, Harvard University School of Medicine in Boston.

May I inquire for the record, is it Dr. Biggers, Dr. Zinder, Dr. Edelman?

Gentlemen, I hate to say this, but we have just been alerted that there is a vote going on. Rather than get started and have to interrupt in about 5 minutes, I think it would be better for you and for us if we ask you to forgive us. We will be back as quickly as we can. [A brief recess was taken.]

Senator BAYH. May we reconvene our hearings, please?

Professor Edelman, I understand that you are going to be the leadoff witness.

STATEMENT OF GERALD M. EDELMAN, M.D., PH. D., PROFESSOR, ROCKEFELLER UNIVERSITY

I am

Dr. EDELMAN. Mr. Chairman and members of the subcommittee, pleased to have this opportunity to testify in these hearings. Perhaps I should begin by identifying my fields of expertise and by briefly discussing my background. Although I am a professor at the Rockefeller University in New York, I do not represent that institu

tion here.

Rather, I speak as a scientist with some experience in cell biology and in molecular biology, and also as a concerned citizen. My main fields of scientific inquiry are immunology—or how the body distinguishes self from not-self-and various areas of cell biology, particularly cell growth and division, and the analysis of the structure of spermatozoa, including those from human beings.

I was first educated as a physician and after a year of medical training at the Massachusetts General Hospital, spent 2 years in general practice, including obstetrics, as a Captain in the United States Army. Subsequent to that, I obtained a doctoral degree in protein physical chemistry. For the last 14 years, I have spent most of my time doing medical research. In 1972, I was the recipient of the Nobel Prize in Physiology or Medicine for work on the chemical structure of antibodies.

As I understand it, one of the main questions before this committee is whether we can tell when life, particularly human life, begins. I hope to show that, from the scientific point of view, this question is unanswerable, because it is not formulated in terms that can be dealt with operationally. It is important, I believe, to make this remark before getting to any substantive matters, in order to avoid large amounts of useless rhetoric. I should add that it is equally useless to comment on tautologies represented by statements that, for example, "the union of the sperm and the egg represents the first occasion in which the full genetic potential exists for the growth of an animal", a statement which is undeniable by logic alone.

The detailed comments I shall make about the role of science in such matters may sound negative to this subcommittee, but I believe that there are many questions that cannot be answered by scientific experimentation that are nonetheless important and obviously need to be answered. It seems to me that this in no way restricts the value of expert testimony by scientists. Indeed, one of the tasks before this committee is to determine whether the main question can be answered by scientists. I believe it cannot, but also believe that my obligation is to explain why it cannot. If you know what you cannot do, you are way ahead, even in fields outside of the law.

It may seem to this committee, which has heard the strong statements of previous testimony, that this is a weaker position. But I believe that the statements made in that testimony represent a straw man, consisting of a mixture of scientific fact, philosophic conjecture and personal opinion, all represented as scientific.

In rebuttal to this position, I can only say that I know of no scientific paper in any reputable journal that has proven when life indeed begins. If such a paper exists, I would certainly be glad to know of it and to know whether its claims have been verified.

The great advances in modern biology at the level of both living cells and the molecules of which they are made reveal that there is no scientifically sound way of distinguishing the living from the nonliving. For example, viruses have all the properties of living cells except the capacity for independent existence: they contain genetic information and they evolve, they reproduce themselves and they grow. Yet, they have a completely definable molecular structure and they crystallize just as molecules crystallize and may therefore seem

to be dead. At a higher level, it is clear that there is a continuum of properties possessed by cells, tissues, organs and individuals.

If one asserts that a fertilized egg contains a full complement of genes from the father and the mother, and is therefore privileged as "more alive", then counter examples can easily be brought to mind. Biologists have produced complete frogs from eggs alone without sperm and have even produced frogs from the nuclei of skin cells, which contain just as much genetic information as a fertilized egg. Such complete genetic information is, in fact, in every cell of the body except sperm and eggs, yet no one raises issues about the loss of skin cells or even brain cells for that matter. Losing a sperm, or millions of them, or losing an egg each month would on this basis be a horrendous loss, for they too are "alive", yet it occurs normally to everyone.

Senator BAYH. Excuse me, Dr. Edelman.

Has that type of reproduction that you alluded to, as far as the frog is concerned, ever been done in a human being?

Dr. EDELMAN. No, sir. But a frog, as far as we know, reproduces by the same processes in the fundamental sense as a human being, and that experiment has definitely been carried out. The nucleus of a frog's skin cell has been placed inside the cytoplasm of an egg, and a complete frog has been produced. That is because that skin cell, like every cell in your body, carries a complete complement of genes from both the mother and the father.

Senator BAYH. When did this experiment take place?

Dr. EDELMAN. That experiment was done by Gurdon in Oxford, England in 1971. I am not exactly sure of the earliest paper.

Senator BAYH. Is there something unique about the cell of a frog as distinguished from the cell of a human being that would allow these developments 2 or 3 years ago as far as frogs are concerned, and the same formula not apply to the reproduction of a human?

Dr. EDELMAN. As far as I know, this experiment has not been extensively tried in all of its details, until say 10 years ago, and it is a relatively new technique which is just being explored. The experiment at the level of amphibians is a success, and the information involved in that experiment and the conclusions to be drawn are these: that the genetic information is contained in every cell of the body sufficient to create an individual frog.

Senator BAYH. Excuse me for interrupting.

Dr. EDELMAN. Well, from this point of view, I believe that a zygote needs no more protection from the law than an egg.

If one somehow attempts to glorify a fertilized egg or even an early embryo, one must confront questions that are not capable of scientific answers. At what step of development does a living, individual human being appear? This is essentially a religious and moral question and is therefore open to sectarian interpretations and prejudices.

Science, can assert that people are not cells or just collections of cells. It is the set of capacities of a whole person, for example, the capacity to be conscious, self-aware, develop and absorb culture that defines an individual. Although a fetus may have the potential for these, it has no more than any other collection of cells and certainly has not these capacities.

57-676 76 - 17

Incidentally, equal difficulties attend the definition of death, which also requires the interaction and evaluation of nonscientific agencies such as the law and various religious groups.

An even more difficult question relates to the issue of the appearance of consciousness and individuality in terms of information and self-awareness. There is no generally accepted scientific proof that a fetus has consciousness in the sense of self-awareness.

If that is what is presumed to be there a priori according to some nonscientific belief, then of course we can extrapolate to value judg ments as we wish, and say that in an abortion something dies that we think is human. But that would be no more scientifically valid than the assertion that a fertilized egg is the first occasion that all the requisite information for a human being is brought together and is therefore on that basis somehow sacred. In any case, even nonscientists differ in their views on these questions depending on their prior beliefs. The fact is that people had a full spectrum of such beliefs even before scientists found out the structural details of DNA. spermatozoa, eggs, fetuses, and human development. It is likely that this spectrum of beliefs will exist even after much more is known scientifically about these things.

It is debatable that abortions will play a role in whether the human race survives or not. Whatever one's position in this debate, it is a scientifically inaccurate position to contend that a fertilized egg represents a unique privileged biological state or that there is a uniquely definable moment of conception. No amount of personal scientific credentials can justify this assertion as scientific in the face of so many factual counterexamples of the kind that I have mentioned, and in the face of questions of value with which science cannot deal.

Having said this much, and particularly because I have taken this position, I must express my opinion as an individual citizen. I believe that it is an infringement upon the rights of a woman to tell her what to do with her eggs, fertilized or not. I believe that the development of a humane and lawful position and example on this matter in every nation is a good thing and a hope for less privileged

nations.

Finally, I believe that the dignity and freedom and individuality of persons does not rest on arbitrary pseudoscientific definitions but on the consideration of all facts and values in a pluralistic manner. This evaluation involves legal precedent and religious beliefs, and it must be settled by law, for it cannot be settled by scientific experiment. The role of scientists in such an issue is to tell people what scientists know, what science can do and what science cannot do. The decision must then be made on larger grounds, not by some simple appeal to scientific technology nor according to the dogmas of any single group, however sincere its beliefs.

I hope you find these remarks of some use. Thank you.
Senator BAYH. Thank you, professor.

STATEMENT OF GERALD M. EDELMAN, M.D., PH.D.

Mr. Chairman, and members of the subcommittee: I am pleased to have this opportunity to testify in these hearings. Perhaps I should begin by identify ing my fields of expertise and by briefly discussing my background. Although I am a Professor at the Rockefeller University in New York, I do not repre

sent that institution here. Rather, I speak as a scientist with some experience in cell biology and in molecular biology, and also as a concerned citizen. My main fields of scientific inquiry are immunology (or how the body distinguishes self from not-self) and areas of cell biology, particularly cell growth and division, and analysis of the structure of spermatozoa, including those from human beings.

I was first educated as a physician and after a year of medical training at the Massachusetts General Hospital, spent two years in general practice, including obstetrics, as a Captain in the United States Army. Subsequent to that, I obtained a doctoral degree in protein physical chemistry. For the last fourteen years., I have spent most of my time doing medical research. In 1972, I was the recipient of the Nobel Prize in Physiology or Medicine for work on the chemical structure of antibodies.

As I understand it, one of the main questions before this committee is whether we can tell when life, particularly human life, begins. I hope to show that, from the scientific point of view, this question is unanswerable, because it is not formulated in terms that can be dealt with operationally. It is important, I believe, to make this remark before getting to any substantive matters, in order to avoid large amounts of useless rhetoric. I should add that it is equally useless to comment on tautologies represented by statements that "the union of the sperm and the egg represents the first occasion in which the full genetic potential exists for the growth of an animal," a statement which is undeniable by logic alone.

The detailed comments I shall make about the role of science in such matters may sound negative to this subcommittee, but I believe that there are many questions that cannot be answered by scientific experimentation that are nonetheless important and need to be answered. It seems to me that this in no way restricts the value of expert testimony by scientists. Indeed, one of the tasks before this committee is to determine whether the main question can be answered by scientists. I believe it cannot, but also believe that my obligation is to explain why it cannot. If you know what you cannot do, you are way ahead, even in fields outside of the law.

It may seem to this committee, which has heard the strong statements of previous testimony, that this is a weaker position. But I believe that the statements made in that testimony represent a straw man, consisting of a mixture of scientific fact, philosophic conjecture and personal opinion, all represented as scientific. In rebuttal to this position, I can only say that I know of no scientific paper in any reputable journal that has proven when life indeed begins. If such a paper exists, I would certainly be glad to know of it and to know whether its claims have been verified.

The great advances in modern biology at the level of both living cells and the molecules of which they are made reveal that there is no scientifically sound way of distinguishing the living from the non-living. For example, viruses have all the properties of living cells except the capacity for independent existence: they contain genetic information and they evolve, reproduce themselves and grow. Yet, they have a completely definable molecular structure and they crystallize just as molecules crystallize and may therefore seem to be "dead." At a higher level, it is clear that there is a continuum of properties possessed by cells, tissues, organs and individuals. If one asserts that a fertilized egg contains a full complement of genes from the father (sperm) and the mother (unfertilized egg), and is therefore somehow privileged as "more alive," counter examples can easily be brought to mind. Biologists have produced complete frogs from eggs alone without sperm and have even produced frogs from the nuclei of skin cells which contain just as much genetic information as a fertilized egg. Such complete genetic information is, in fact, in every cell of the body except sperm and eggs, yet no one raises issues about the loss of skin cells or even brain cells for that matter. Losing a sperm (or millions of them) or losing an egg each month would on this basis be a horrendous loss, for they too are "alive" yet it occurs normally to everyone. From this point of view, a zygote needs no more protection from the law than an

egg.

If one somehow attempts to glorify a fertilized egg or even an early embryo, one must confront questions that are not capable of scientific answers. At what step of development does a living, individual human being appear? This is essentially a religious and moral question and is therefore open to sectarian interpretations and prejudices. Science, of course, can assert that people are not cells or just collections of cells. It is the set of capacities of a whole per

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