CS: Sure. Why not? Well, there's no question that the discovery of something very different will worry people precisely because it's different. Look at the degree of xenophobia in human cultures in which it is other humans, trivially different from us, who are the object of great fear and concern and violence and aggression and murder and terrible crimes. So there's no question that were we to receive a signal, much less come face-to-face, or whatever the appropriate bodily part is, with another intelligent being, there would be a sense of fear, horror, loathing, avoidance, and so on.
But the receipt of a message is a very different story. You are not even obligated to decode. If you find it offensive, you can ignore it. And there is a kind of providential quarantine between the stars, with very long transit times even at the speed of light, that I think obviates, if not altogether eliminates, this difficulty.
CS: The questioner asks that is not one central goal of religions the idea of a personal god, of a purpose for individuals and for the species as a whole, and is that not one of the reasons for the success on an emotional level (I'm paraphrasing) of many religions? And he then goes on to say that he, himself, does not see much evidence in the astronomical universe for a purpose.
I tend very much to agree with you, but I would say that purpose is not imposed from the outside; it is generated from the inside. We make our purpose. And there is a kind of dereliction of duty of us humans when we say that the purpose is to be imposed on the outside or found in some book written thousands of years ago. We live in a very different world than we lived in thousands of years ago. There is no question that we have many obligations to guarantee our purposes, one of which is to survive. And that we have to work out for ourselves.
CHAPTER TWO
Questioner: What is your opinion on the nature of the origins of intelligent life in the universe? CS: I'm for it!
CHAPTER FOUR
Questioner: I'm a wee bit skeptical at Drake's equation. It doesn't really indicate how much extraterrestrial life there is. All it indicates is whether the user of it is a pessimist or an optimist. And given this, why do you bother to use it at all?
CS: That's a perfectly good question. And it has a perfectly good answer. And that is, it might have turned out before you went through this exercise that even in the optimistic case the number of civilizations was so low that it didn't make sense to search. But it doesn't turn out that way. There's a sequence of perfectly plausible numbers that lead to a large number of civilizations. It doesn't say it's guaranteed, but it survives the initial test. That's the only function that this has, apart from the very nice fact that there is a single equation that connects stellar astrophysics, solar-system cosmogony, ecology, biochemistry, anthropology, archaeology, history, politics, and abnormal psychology.
Questioner: Oh, this scares the hell out of me. But there's one fact that I think Professor Sagan hasn't brought into account in Drake's formulation. The point is that he's only taken this galaxy into account and not all the other-I don't know- thousands or millions of other galaxies, way back to the big bang 15,000 million years ago. So, I mean, if you're going to take that particular formula, why don't you multiply it by that particular factor?
CS: Again, a good question, and I was merely talking about the justification for the search for signals from advanced civilizations in our galaxy. Clearly you can imagine them in some other galaxy. For their signals to reach us here, they have to have a technology far in advance of ours, but that's perfectly possible. And in fact Frank Drake and I have made a search of just a few nearby galaxies with exactly that idea in mind. We found nothing at the few frequencies we looked at. But, you see, once you start imagining signals coming from another galaxy, then you are into significant power levels and therefore significant dedication by some other civilization to try to make contact with what for them would be a distant galaxy. If you imagine civilizations in our own galaxy, you can at least contemplate that they know that this solar system is a plausible abode for life, even if they haven't visited here to check it out, that there's some way that they could target our particular region of the galaxy for a specific message. There's no way that this could be the case from a distant galaxy, as far as I can see.
This does remind me, though, that I forgot to say something. Very nearby civilizations can detect our presence, and that is because television gets out. Not just television but radar. Radar and television get out. Most of AM radio, for example, doesn't. So let's just look at the television for a moment. Large-scale commercial television broadcasting on Earth begins when? In the late 1940s, mainly in the United States.
So forty years ago there's a spherical wave of radio signals that spreads out at the speed of light, getting bigger and bigger as time goes on. Every year later it's an additional light-year away from the Earth. Now, let's say it's forty years later, so that expanding spherical wave front is forty light-years from the Earth, containing the harbingers of a civilization newly arrived in the galaxy. And I don't know if you know about 1940s television in the United States, but it would contain Howdy Doody and Milton Berle and the Army-McCarthy Hearings and other signs of high intelligence on the planet Earth. So I'm sometimes asked, if there are so many intelligent beings in space, why haven't they come here? Now you know. It's a sign of their intelligence that they haven't come. (I'm just joking.) But it's a sobering fact that our mainly mindless television transmissions are our principal emissaries to the stars. There is an aspect of self-knowledge that this implies that I think would be very good for us to come to grips with.
CHAPTER FIVE
Questioner: How do you recognize the truth when it is upon us?
CS: A simple question: How can we recognize the truth? It is, of course, difficult. But there are a few simple rules. The truth ought to be logically consistent. It should not contradict itself; that is, there are some logical criteria. It ought to be consistent with what else we know. That is an additional way in which miracles run into trouble. We know a great many things-a tiny fraction, to be sure, of the universe, a pitifully tiny fraction. But nevertheless some things we know with quite high reliability. So where we are asking about the truth, we ought to be sure that it's not inconsistent with what else we know. We should also pay attention to how badly we want to believe a given contention. The more badly we want to believe it, the more skeptical we have to be. It involves a kind of courageous self-discipline. Nobody says it's easy. I think those three principles at least will winnow out a fair amount of chaff. It doesn't guarantee that what remains will be true, but at least it will significantly diminish the field of discourse.
Questioner: Have you any comments to make on the Shroud of Turin?
CS: The Shroud of Turin is almost certainly a pious hoax; that is, not a contemporary hoax but a hoax from the fourteenth century, when there was significant traffic in pious hoaxes. And my technical knowledge of the Shroud of Turin comes from Dr. [Walter] McCrone of Chicago, who has worked on it for some years. He found the "blood" to be iron oxide pigments, and there is nothing that cannot be explained by the technology available in the fourteenth century. By the way, there is no provenance of the Shroud of Turin earlier than the fourteenth century [8] So I'm sorry that my knowledge is secondhand on this issue, and I know that there are people who believe, for reasons that are apparent. No, I'm sorry. I haven't said that fairly. There are people who believe that it is the authentic death shroud of Jesus on the cross. But the evidence is very meager.