The Varieties of Scientific Experience: A Personal View of the Search for God

by Carl Sagan

  Well, my only response is that this is a claim that, from my point of view, remains to be proved. I would have to ask, "What is the evidence that we are more than material beings?" I don't think anyone would doubt that matter is a part of our makeup. And the question is, what is the compelling evidence that it is not all?

  Questioner: Sir, I have a feeling that we have a lot of growing to do. The scientist doesn't perhaps know yet how to bring a greater being into the picture, and suddenly there are psychic things that are spiritual. You're taking the wrong set of faculties to disprove the psychic element. You must use the similar faculty. So it will be hundreds of years before scientists can ever prove the psychic part of life.

  CS: Would you grant the possibility that there is no psychic part of life?

  Questioner: No.

  CS: Not a possibility? Not a smidgen of doubt in your mind?

  Questioner: I'm one of those who lives with one foot on each side of life. One foot on the psychic and a very practical other foot, as a businesswoman, on the world. I've proved it.

  CS: What in general should we do in a dialogue like this? Here I am. I say that my mind is open. I am happy to see the evidence, and the response I sometimes get is, "I've had this experience. It's compelling to me. But I can't give it over to you." Now, doesn't that prevent any dialogue whatever? How are we to communicate?

  Questioner: Well, you see, I think you're stopping with the mental faculties you have and saying, "This is me. This is wrong." Now, there are faculties that one could certainly not create, because they're already in the mind, spiritual faculties.

  CS: Well, you see, I say they're not-that's not demonstrated- that there's no evidence that they exist. First you have to show that they exist before you can have a major program to encourage them.

  Questioner: I don't know that you have to play the piano to know that you can.

  CS: No. But I can require, at least, before I start practicing the piano that I see that a piano exists, that I see someone sit down at the piano, move his or her fingers, and produce music. That then convinces me that there is such a thing as a piano, there is such a thing as music, and it is not hopelessly beyond the ability of humans to produce music from a piano. But when I ask for something comparable in the psychic world, I am never shown it. I never have someone come up and produce an-I don't know-a twenty-foot-high psychic dragon. Or have someone come and write down on the blackboard the demonstration of Fermat's last theorem. There simply is never anything that you can get your teeth into. You understand why I feel a little frustrated about this?

  Questioner: I do. Yes. But then you possess faculties that can open that door to you.

  CS: You're relying on me to find the psychic world? No.

  Questioner: I'm hoping every individual can find it for themselves. It's a question of education within oneself.

  CS: I believe that before we do the education, we have to first demonstrate that there is something to be educated on. I don't for a moment maintain that there isn't an enormous amount we have yet to learn. I believe that we have in fact discovered the tiniest fraction of the wonders of nature that are out there. But I just think until those who believe in the spiritual or psychic or whatever-you-want-to-call-it world can actually demonstrate in any way its existence, that it is not likely that scientists will be devoting a great deal of their time to adumbrating this possibility.

  Questioner: How dependable an evidence would you say is the electroencephalograph readings that have been taken in certain experiments on those who practice different types of meditation, perhaps from the Eastern teachings, and have been able to record more central brain-wave patterns during a time when the physical senses have been shut off and the mind has gone deep into the conscious, subconscious, unconsciousness if you like? That was done at Berkeley University [the University of California, Berkeley] with a good friend of mine, where she was put into a simulated environment to create these circumstances.

  CS: Well, I certainly agree that there is such a thing as the unconscious mind. There is all sorts of evidence for it in our everyday lives, and Freud provided a compelling argument that it exists. And I think it is essential that we understand it, and I believe that it plays a powerful, maybe even dominant, role in international relations, and that's therefore a very practical reason for understanding it.

  I also believe that there are altered states of consciousness that can be brought about by some-it's related to what I said before-by sensory deprivation and by certain molecular assists. But I don't know of any evidence that it isn't a different mode of interaction of the molecules in our brain, a different sequence of flashing connections of neurons; that is, that there are other ways in which the brain works is guaranteed. That we don't fully understand those ways is also guaranteed. But that this is something other than matter-not a smidgen of evidence for that. Is that responsive?

  Questioner: Yes it is.

  CS: Thank you.

  Questioner: Professor Sagan, this is a question on the God hypothesis. Don't you think that science, out of habitually having to find the answers for material things and having to be seen to attempt to find the answers, subject to public pressure and admiration, has ventured on this occasion into religious territory on which it should perhaps make a more cautious approach, in relation to your own admitted lack of scrupulous proof and unsubstantial faith? To my mind I thought science was a servant of mankind and not mankind a servant of science.

  CS: I certainly agree with the last sentence, but I don't see how that is connected with the rest of what you said. My personal sense is that there are limitations, of course, to science, and I just indicated what a tiny fraction of the world I think we understand. But it is the only method that has been demonstrated to work. And if we bear in mind how liable we are to be deceived, to deceive ourselves-that was the point of some of the UFO discussions we had-then it is clear that what we need is a very hard-nosed and skeptical approach to contentions that are made in this area. And that hard-nosed and skeptical approach has been tested and honed, and it is called science.

  "Science" is only a Latin word for "knowledge." And it's hard for me to believe that anyone is opposed to knowledge. I think that science works by a careful balance of two apparently contradictory impulses. One, a synthetic, holistic, hypothesis-spinning capability, which some people believe is localized in the right hemisphere of the cerebral cortex, and an analytic, skeptical, scrutinizing capability, which some people believe is localized in the left hemisphere of the cerebral cortex. And it is only the mix of these two, the generating of creative hypotheses and the scrupulous rejection of those that do not correspond to the facts, that permits science or any other human activity, I believe, to make progress.

  As far as me bringing a scientific approach to the matters of religion, I think that is implicit in inviting a scientist to give the Gifford Lectures. I could hardly have left my science outside the door as I walked in. I would have appeared before you naked.

  Questioner: Just at the end of your lecture, you referred to Bertrand Russell saying that you should not believe a proposition that you do not have good grounds for believing to be true.

  Now, surely that in itself is a proposition. What grounds would you have for believing that proposition?

  CS: Yes. That's a very good question that leads to an infinite regress. And notice that Russell said he would merely propose for our consideration this proposition. Russell was, in his mathematician incarnation, the author of precisely such logical paradoxes as the one you just suggested. So if you wish to have the statement justified in internal logic-that is, a self-consistent closed system-obviously it cannot, because it leads to an infinite regress. But as I was saying, it seems to me that the approach of skeptical scrutiny commends itself to our attention because it has worked so well in the past. So many findings-I tried to give some simple physical and astronomical ones in the earlier lectures-were made possible by science not accepting the conventional wisdom, not taking o
n blind faith what was taught in the religious and secular schools, that everybody knew-the teachings of Aristotle on physics and astronomy, for example-but instead by asking, "Is there really evidence for it?" It is the method of science. And at every step along the way, it has produced some agonizing reappraisals and some powerful emotions that don't like it. And I understand that very well. But it seems to me that if we are not dedicated to the truth in this sense of truth, then we are in very bad shape.

  CHAPTER EIGHT

  Questioner: How serious do you think the problem is with the creationists that are in the States?

  CS: Well, different people will have a different answer. Some fundamentalist Christians believe that it is without any doubt that the world will end shortly, that the signs, especially the formation in 1948 of the state of Israel, are clear; that is, there are many fundamentalist Christians, at least in the United States-I don't know about elsewhere in the world-who deeply believe that this is true. And there will be a tribulation and a rapture, and there's an entire mythology about the events that will happen. We are even told by the Reverend Mr. Falwell that believing Christians, when the trumpet is sounded, will be taken bodily to heaven. And if they are driving a car or flying an airplane at that moment, then the car and airplane containing its nonbelieving passengers are in some difficulty. The conclusion of which would seem to be that there has to be a test of faith before issuing a license.

  Questioner: You seem to think that in the event of a nuclear war, all human beings may become extinct. I put the question on the grounds of two things that you didn't bring up at all in your talk: One, nuclear power stations will be damaged in a nuclear war, and that will leak radiation that will be dangerous for thousands of years, and two, we don't know the effects of ultraviolet light that may come through to Earth after a nuclear war.

  CS: Right. So the questioner says, is it clear that other forms of life would survive bearing in mind the enhanced ultraviolet flux from the destruction of the ozone layer and the radioactive fallout, especially if nuclear power plants are targeted. I chose grasses and cockroaches because of their high radiation resistance. And if you check it out, you find that they are several orders of magnitude more resistant than humans are. A typical dose of radiation to kill a human being is a few hundred rads. There are organisms that are not killed until a few million rads. Also, the sulfur-eating marine worms that I mentioned, they were not selected randomly either. They live entirely at the ocean bottom where no ultraviolet light can get and where they are quite well insulated against radioactivity in the environment. So for those reasons I still say that many forms of life would survive, and its clear from past mass extinctions like the Cretaceous-Tertiary event that many forms of life have survived in the past what were probably more serious events than a nuclear war, although it's quite true that the radioactivity was not a component of such events in the past.

  Questioner: As a scientist, would you deny the possibility of water having been changed into wine in the Bible?

  CS: Deny the possibility? Certainly not. I would not deny any such possibility. But I would, of course, not spend a moment on it unless there was some evidence for it.

  CHAPTER NINE

  CS: There was one question that was sent to me in a letter to my hotel, which was signed, "God Almighty." Probably just to attract my attention. It said that the writer's definition of a miracle would be if I would answer the letter. So to show that miracles can happen, I thought I would answer the question. The question was a straightforward and important one, often asked: "If the universe is expanding, what's it expanding into? Something that isn't the universe?"

  Well, the way to think of this is to remember that we are trapped in three dimensions, which constrains our perspective (although there's not much we can do about being trapped in three dimensions). But let us imagine that we were two-dimensional beings. Absolutely flat. So we know about left/ right and we know about forward/back, but we've never heard of up/down. It is an absolutely incoherent idea. Just nonsense syllables. And now imagine that we live on the surface of a sphere, a balloon, let's say. But of course we don't know about that curvature through that third dimension, because that third dimension is inaccessible to us, and we cannot even picture it. And now let's imagine that the sphere is expanding, the balloon is being blown up. And there is a set of spots on the balloon, each of which represents, let us say, a galaxy. And you can see that from the standpoint of every galaxy all the other galaxies are running away. Now, where is the center of the expansion?

  On the surface of the balloon, the only part of it that the flat creatures can have access to, where is the center of the expansion? Well, it isn't on that surface. It's at the center of the balloon in that inaccessible third dimension. And, in the same way, into what is the balloon expanding? It is expanding in that perpendicular direction, that up/down direction, that inaccessible direction, and so you cannot, on the surface of the balloon, point to the place into which it is expanding, because that place is in that other dimension.

  Now up everything one dimension and you have some sense of what people are talking about when they say that the universe is expanding. I hope that that was helpful, but considering the auspices of the writer, you should have known it anyway.

  Questioner: A program from the Reagan administration was over the television last week. Mr. Paul Warnke stated that Star Wars [the Strategic Defense Initiative, or SDI] would fail.

  CS: Well, maybe I should just say a few words about Star Wars. Star Wars is the idea that it's dreadful to be threatened with mass annihilation, especially at the hands of some people you've never met, and wouldn't it be much better to have an impermeable shield that protects you against nuclear weapons, to simply shoot down the Soviet warheads when they're on their way here? And as an idea it's an okay idea. The question is, can it be done? And let me not quote the legion of technical experts who believe that it is nonsense. Let me instead quote its most fervent advocates in the American administration, in the Department of Defense. They say that after some decades and the expenditure of something like one tr-Well, they don't actually say the expense, but it's an expenditure of something like one trillion dollars, that the United States might be able to shoot down between 50 and 80 percent of the Soviet warheads.

  Let us imagine that the Soviet Union does nothing in the next few decades to improve its offensive capability; it leaves everything (a very unlikely possibility) at its present offensive force- that's ten thousand weapons. Ten thousand nuclear warheads. Let us give the benefit of the doubt to the exponents of Star Wars and imagine that instead of 50 to 80 percent they can shoot down 90 percent of the warheads. That leaves 10 percent that they cannot shoot down.

  Ten percent of ten thousand warheads is (an arithmetical exercise accessible to everyone) one thousand warheads. One thousand warheads is enough to utterly demolish the United States. So what are we talking about?

  The advocates say it can't protect the United States. And there are many other things that could be said about it, but I think that is a key point. Its advocates think it won't work. And it will cost a trillion dollars. Should we go ahead?

  Questioner: Do you think that your people will go ahead?

  CS: Why do something so foolish? A very good question. And here we are getting into murky issues of politics and psychology and so on, but I don't believe in ducking questions-I'll tell you what I think. I think that the alternative is abhorrent to the powers that be. The alternative is that you negotiate massive, verifiable, bilateral reductions in nuclear weapons, which would be an admission that the entire nuclear arms race has been foolish beyond belief, and that all of those leaders-American and Russian and British and French-for the last forty years, who bought this bill of goods put their nations at peril. It is such an uncomfortable admission that it takes great character strength to admit to it. So I think that rather than admit to it we are looking at a desperate attempt to have still more technology to get us out of the problem that the techn
ology got us into in the first place. The ultimate technological fix. Or, as it is sometimes called, "the fallacy of the last move." Just one more ratchet up the arms race, please let us have it, and then everything will be fine forever. And if there's anything that's clear from the history of the nuclear arms race, it's that this isn't the case. Each side, generally the Americans, invents a new weapons system, and then the other side, generally the Soviets, invents it back. And then both nations are less secure than they were in the first place, but they've spent a charming amount of money and everybody's happy. Now, there's no question that if you wave a trillion dollars at the world aerospace community, you will have organizations, corporations, military officers, and so on interested in it, whether or not it will work.

  And I'm sure that this is a part of it. But it's not the main part. The main part is a tragic reluctance to come to grips with the bankruptcy of the nuclear arms race. In the United States, it's eight consecutive presidents, something like that, of both political parties, that have bought it. Most of the people who run the country are advocates of the nuclear arms race, or have been in the past. It's very hard to say, "Sorry, we made a mistake," on an issue of this size. That's my guess.

  Questioner: I think for the first time yesterday President Reagan offered to share the technology of SDI with the Russians.

  CS: It's not the first time. He's been saying that all along.

  Questioner: Yeah, but isn't it perhaps preferable that the joint efforts of the great powers be extended for perhaps defensive matters rather than the offensive weapons that have occupied them for so long?

  CS: No, I don't agree. We're talking about a shield. Let's imagine another kind of shield, the contraceptive shield. Let's suppose that the contraceptive shield lets only 10 percent of the spermatozoa through. Is that better than nothing, or isn't it? I maintain that that's worse than nothing-among other things, for giving a false sense of security. But on the idea of sharing the technology, this is an administration that will not give an IBM personal computer to the Soviets. And we are asked to believe that the United States will hand over the eleventh-generation battle-management computer, which is decades off, and which will be so complicated that its program cannot be written by a human being or any collection of human beings. It can be written only by another computer. It cannot be debugged by any human being. It can be debugged only by another computer. And it can never be tested except in a nuclear war itself. And this we will hand over to the Russians? In either case, if we believed it would work or if we didn't believe it would work, I can't imagine the Russians saying, "Thank you very much. We will now have this as the principal mainstay of the security of the Soviet Union, this program that the Americans have very kindly just given over to us."