Combining Estimated Risks When Using The Doomsday Argument

The estimated total risk of Doom Soon cannot possibly exceed 100 per cent, no matter how greatly it is magnified by doomsdayargument considerations. It is therefore very wrong to apply these considerations to risks taken individually. We need to consider the entire packet. Suppose, for example, that we started by thinking that the risk associated with high-energy experiments stood at 1 per cent, the only other cloud on the horizon being a 9 per cent risk associated with pollution. The doomsday...

War Pollution Disease

In this chapter and the next, so many risks are listed that it could seem surprising that the human race has survived so long. Now, it might indeed be surprising (although of course if the race hadn't survived, then we'd not be here to observe and discuss the matter). On the other hand, it may well be that the risk of extinction has so far been fairly low. What then needs to be feared is a sudden increase in various dangers. The chapter expands points made in the Introduction about well-known...

Could Schopenhauers gloom have been right

Suppose some political leader becomes able to create planet-wide nuclear explosions just by pulling a lever. Given sufficiently many explosions in a sufficiently short period, nobody would suffer pain or disappointment. Living normally at one moment, we should all be gas and ashes at the next. What could be unfortunate here Schopenhauer argued that every human life is inevitably miserable on the whole. Humans, he wrote, concentrate not on such things as the general health of their bodies, but...

Some Further Examples Of Attempted Refutations

The doomsday argument itself is reasonably straightforward. ('We should tend to distrust any theory which made us into very exceptionally early humans.' This is hardly a very difficult thought, is it ) What can make the argument seem highly complicated is the need to guard it against a hundred criticisms. Because of the intricacies in which we are then entangled, a thorough discussion of the area will be deferred until Chapters 5 and 6. Still, many people might like to learn straight away how...

Genetic Engineering

Quite apart from its possible contributions to biological warfare (see Chapter 1), genetic engineering might be considered extremely dangerous. The fact is that the complexity of the field makes its risks very hard to evaluate. At least in public, most experts say they are no great cause for concern, as shown both by calm scientific reasoning and by the absence of any disaster so far see, for example, chapter 3, 'The fear and trembling', of B.K. Zimmerman's Biofuture, with its talk of 'poor...

General Problems Of Risk Analysis

Analysing risks is a discipline with a large literature, including the journal Risk Analysis for a quick introduction see M.G.Morgan's 'Risk analysis and management'.1 So far, though, the field's complexities have made it only rather poorly developed. The fact that smoking puts you in grave danger of cancer and other diseases was doubted for quite some time by statisticians, yet the latest findings from a forty-year study of British doctors indicate that one smoker in two will die from the...

The Doomsday Argument Recapitulation And Then New Comments

As this chapter,1 like the others, is intended to be readable in isolation, it starts with a brief recapitulation. The doomsday argument, originated by B.Carter and then published and defended by J.Leslie, with variants by J.R.Gott and H.B.Nielsen, points out that you and I would be fairly unremarkable among human observers if the human race were to end shortly roughly 10 per cent of all humans born up to today are because of the recent population explosion living at this very instant. If, in...

Additional Note For Physicists

A variant on the doomsday argument appears to destroy manyworlds quantum theory.11 Or at least, it would seem to destroy those variants of many-worlds quantum theory in which, as was fairly plainly intended by the theory's first inventor, H.Everett, every observer splits at each successive moment into vastly more 'versions' of himself or herself one version for each possible set of observations which the laws of quantum physics allow to flow from the situation at the previous moment.12 If they...

The case corresponding to an indeterministic world

How can our thought experiments be made to mirror an indeterministic world The solution is simple enough. We can vary them by placing God's throw of the dice at a time later than the creation of the small-room people. Once again you find yourself in the small room. Can you conclude anything about the fall of the dice Let's specify, just as before, that God's dice are radically indeterministic. How they would fall couldn't have been settled by the situation at any earlier time. Let's say you...

The case where the total number to be created was settled in advance

Suppose you further know (1) that the dice behaved in a radically indeterministic manner, so that there had been no possibility of being sure in advance how they would fall (2) that you've strong initial reasons to suspect the dice were loaded (which nicely reflects our frequent sense of insecurity when estimating probabilities) (3) that the large room was to be filled unless the throw was a double-six and (4) that the throw was made before God created any people at all, while immediately after...

Just Who Should Count As Being Human

Now, what about the doomsday argument's 'reference class' Who ought to be considered 'humans' for its purposes Looking towards the past, at what date shall we say that humans first diverged from the manlike apes Imagining the future, should we still call a race 'human' when it had undergone great evolutionary changes With respect to the past, an initial reaction might be that it would scarcely matter where we drew the line between humans and non-humans. The numbers involved would be much the...

Carters doomsday argument

After what has just been said, it should come as no surprise that some centrally important principles of risk analysis have only lately been noticed and are sometimes violently resisted. Brandon Carter's doomsday argument is a prime example. As will be examined at greater length in Chapter 5, the argument exploits the fact that we ought to prefer (other things being equal) those theories whose truth would have made us more likely to find whatever we have in fact found. While this might seem...

The greenhouse effect

Greenhouse gases let thr ough sunlight but tend to stop energy escaping into space when it has been changed to lower-frequency heat radiation. While water vapour is the main such gas, there are growing contributions from over thirty others, especially CO (carbon dioxide), nitrogen oxides, methane, fluorocarbons (CFCs, HCFCs and HFCs), and lower-atmosphere ozone. Humans produce over thirty billion tons of CO annually, two-thirds of it by burning fossil fuels at a rate which has increased...

Not Striking Second The Rights And Wrongs Of Nuclear Revenge

When a nation has carried out a nuclear first strike with thousands of bombs, what could be the point of retaliating As a utilitarian I see moral point in actions only when they stand a chance of doing some good. Those who follow Kant might well have little difficulty in viewing nuclear revenge as 'avenging justice'. Kant speaks of the need to execute murderers even though the heavens fall. But I don't admire Kant's approach. How could you have a duty to do something which would harm some...

Threats To The Survival Of The Human Race

Estimating the probability that the human race will soon become extinct has become quite a popular activity. Many writers have considered such things as the dangers of nuclear war or of pollution. This book will make few claims to expertise about the details of such highly complex matters. What it will claim instead is that even non-experts can see that the risks aren't negligible. In view of how much is at stake, we have no right to disregard them.2 Besides, even if the 'total risk' (obtained...

The population crisis

Malthus, writing in 1825, when Earth's population had just risen rapidly to nearly one billion, predicted that it would very soon reach the limit which the planet could support, after which it would fall sharply because of famines, epidemics and wars. In fact it proceeded to double in a century, doubling yet again in the subsequent halfcentury. It is now about twenty-five times greater than at the time of Christ, and growing at a quarter of a million people per day. The doubling time is down to...

Naturally Occurring Diseases

Infectious diseases cause roughly half of all deaths today. The organisms producing them fall into four main groups bacteria, viruses, the rickettsiae, which lie between bacteria and viruses in complexity, and parasites such as the protozoa of malaria and the tiny worms of schistosomiasis. Malaria and tuberculosis are the biggest killers at present, the second slightly in the lead with its roughly three million fatalities per year. However, the 'Spanish influenza' virus of the 1918-19 pandemic...

Determinism Indeterminism And The Doomsday Argument

Although Carter's argument gives grounds for re-evaluating the danger of imminent human extinction, these grounds would (as the Introduction noted) necessarily be weakened in an indeterministic world. Indeterminism would mean that there wasn't yet any suitable 'firm fact of the matter', in theory available to anybody who knew the present situation and the laws of physics in sufficient detail, concerning how many humans remained to be born before humankind became extinct compare the fact that...

Group II

These objections concern the fact that you and I can be sure that we (and maybe also all others like us) are in existence now, regardless of what will come later. (Ila) The far future cannot kill us. That's an obvious truth. Unfortunately (for it would be a great relief to find that the doomsday argument didn't work) this truth could undermine the Carter-Leslie position only if it were assumed, ridiculously, that present-day evidence for future events must be evidence caused by those events....

Creating Quark Matter

We now come to two possible sources of risk which I take much less seriously, although it might be wrong to disregard them entirely. When physicists considered performing experiments at very high energies, fears of vacuum metastability were by no means the first to be voiced. As R.Ruthen writes,110 'Since the beginning of the nuclear age, researchers have met many times to discuss whether there was any chance that a proposed experiment might initiate a catastrophe.' Probably the earliest such...

Exhaustion of foodproducing land and water

Using heavy irrigation and fertilization, modern agriculture sows the same crop again and again land is seldom left to recover ('lie fallow') or planted with nitrogen-fixing clovers. If the soil gives signs of exhaustion, more and more fertilizer is applied until not even this can help. Constant watering leads to salt accumulation, but that too is disregarded until crops fail. Because of enthusiastic pesticiding of the weeds which would hold it together and reduce evaporation, topsoil is more...

Bayesian reasoning

It says that the probability, in view of evidence e, that hypothesis h is correct, grows or shrinks in proportion to any extra or lesser likelihood that you'd have got such evidence if the hypothesis were indeed correct. This is common sense, very widely applicable. The evidence can be that you have won a lottery or have been hit by an arrow or bitten by a dog, or that an observed car is red, or evidence in virtually any other field. The hypothesis, too, can...

Computercaused Disasters And Computer Replacements For Humans

While placing nuclear missiles under computer control could quickly prove disastrous, it is just one example of how catastrophe could come from the computer revolution. Here are some other possibilities (a) As well as being open to sabotage, for instance by a terrorist's bomb whose electromagnetic pulse fries computer circuits throughout a city, complex electrical or electronic networks are subject to largely unpredictable collapse. In 1965 failure of a relay device in an electricity generating...

Is The Doomsday Argument Easily Refuted

Already embattled on other fronts, Carter has presented the doomsday argument only in lectures and seminars, never in print. However, I published it on p. 214 of Universes in a long foot-note. Since then I have investigated it in several articles. The argument is certainly controversial. So far, however, I have managed to find only one good ground for doubting it. Suppose that the cosmos is radically indeterministic, perhaps for reasons of quantum physics. Suppose also that the indeterminism is...

Doomsday And The Anthropic Principle

Carter is particularly well known for his 'anthropic principle'. The principle reminds us that observers, for instance humans, can find themselves only at places and times where intelligent life is possible. Observers couldn't be at the center of the sun, presumably, or in the earliest few seconds of an immensely hot Big Bang. They might even be very unlikely to live before the universe had lasted for many billion years. Many billion years of evolution could be needed before intelligent life...

Bibliography

Adamson, D. 1990 Defending the World, London Tauris. Albert, D.Z. 1994 'Bohm's alternative to quantum mechanics', Scientific American, May, 58-67. Alper, J. 1994 'Earth's near-death experience', Earth, January, 42-51. Alvarez, L.W., Alvarez, W., Asaro, F. and Michel, H. 1980 'Extraterrestrial cause for the Cretaceous-Tertiary extinction', Science, June 6, 1095-1108. Alvarez, W. and Asaro, F. 1992 'The extinction of the dinosaurs', pp. 2856 of J.Bourriau ed. Understanding Catastrophe, Cambridge...

Some opponents of utilitarianism

As indicated, I defend 'utilitarianism' in a fairly strong sense. I accept a fairly firm link between the praiseworthiness of any action and the goodness of its probable results, although bearing in mind such things as a that even a minor risk of producing a very unfortunate result, for instance the extinction of the human race, could justify very major sacrifices, and b that an agent may simultaneously deserve a pat on the back for following the guidance of conscience, and a kick in the pants...

Pollution by chemicals or nuclear radiation

Air, water and soil are threatened by pollution. For a start, there is domestic sewage and garbage. In many places raw sewage enters river, lake or sea. In industrialized countries, people each produce about half a ton of garbage annually. It accumulates in landfill sites which poison groundwaters, or it is burned in ways adding pollutants to the air and concentrating others in the ash. Many elements of the garbage count as hazardous waste, yet much more of this is produced by industry. In the...

Disaster Caused By Nanotechnology

'Nanotechnology' means the use of complex machines whose components are of about a nanometer, a millionth of a millimeter. Building them involves manipulating individual atoms and molecules with great precision. The science involved can be a mixture of chemistry, liquid physics and engineering. In 'There's plenty of room at the bottom',63 R.P.Feynman suggested using machines to construct tinier machines, which would then make yet tinier ones, and so on. Another approach is that of the...

Chemical And Biological Warfare

In the First World War, above a million soldiers were casualties of chlorine, phosgene and mustard gas, over ninety thousand dying. The nerve gases tabun, sarin and soman, discovered but not used during the Second World War, were deadly in far smaller quantities, while the yet more effective VX the United States had four thousand tons of it in 1967 killed when just a few milligrams reached one's skin. Still, an amount sufficient to destroy all the people in China, supposing that they lined up...

Comet Or Asteroid Strike

The human race might be exterminated by a large comet or an asteroid. In 1994 there was heavy media coverage when Jupiter was struck by some twenty kilometer-sized fragments of comet Shoemaker-Levy 9, moving at about sixty kilometers a second. One fragment exploded with an energy of at least six million megatons TNT-equivalent . Less well known is that Howard-Koomen-Michels 1979XI, a comet whose head was larger than the Earth, hit the sun in 1979,1 while in late 2126 the comet Swift-Tuttle, a...