Global population will likely start reducing by 2070

July 19, 2017

The alarmist meme of a global population explosion leading to catastrophic depletion of resources and mass famines was already obsolete 20 years ago. The alarmism reached its peak in the 1970s and 1980s  (peak oil, peak food, peak water, peak resources ….). At least the panicky stridency of the alarmism about a population explosion has long gone (though it has now shifted to become panicky stridency about catastrophic global warming).

The 2017 Revision of the UN World Population Prospects is now available.

  • the world’s population reached nearly 7.6 billion in mid-2017. The world has added one billion people since 2005 and two billion since 1993. In 2017, an estimated 50.4 per cent of the world’s population was male and 49.6 per cent female.
  • the global population is expected to reach 8.6 billion in 2030, 9.8 billion in 2050 and 11.2 billion in 2100, according to the medium-variant projection

However the projections are very sensitive to fertility rates and their development – especially in Africa. Actual fertility rates have always tended to be below UN projections of fertility.

In the 2017 review, the sensitivity to fertility rate is highlighted;

  • Future population growth is highly dependent on the path that future fertility will take, as relatively small changes in the frequency of childbearing, when projected over several decades, can generate large differences in total population.
  • In the medium-variant projection, it is assumed that the global fertility level will decline from 2.5 births per woman in 2010-2015 to 2.2 in 2045-2050, and then fall to 2.0 by 2095-2100.
  • fertility levels consistently half a child below the assumption used for the medium variant would lead to a global population of 8.8 billion at mid-century, declining to 7.3 billion in 2100.
  • fertility has declined in virtually all regions of the world. In Africa, where fertility levels are the highest of any region, total fertility has fallen from 5.1 births per woman in 2000-2005 to 4.7 in 2010-2015. Over the same period, fertility levels also fell in Asia (from 2.4 to 2.2), Latin America and the Caribbean (from 2.5 to 2.1), and Northern America (from 2.0 to 1.85). Europe has been an exception to this trend in recent years, with total fertility increasing from 1.4 births per woman in 2000-2005 to 1.6 in 2010-2015. Total fertility in Oceania has changed little since 2000, at roughly 2.4 births per woman in both 2000-2005 and 2010-2015.

As with Asia, I expect that the decline of fertility in Africa will accelerate with development and GDP growth. If global fertility turns out to be as much as 0.5 children/woman less than the medium assumption, global population will start declining already by 2050. It may not happen quite that fast but it is now very likely that the decline will have begun by 2070. By the end of this century global population may not be much more than it is today.

It is only a matter of time before the alarmists start getting panicky and strident about the impending population implosion.


The edge of the universe is to humans as the surface of the water is to fish

July 18, 2017

Things become weird and wonderful when physicists or cosmologists or astronomers talk about the “edge of the universe” or the “finitely bounded but infinite universe” or the “expanding universe” which does not expand into anything but creates space as it expands (the balloon analogy). I read that the Big Bang occurred 13.8 billion years ago but the size of the universe is said to be a diameter of (around) 93 billion light-years. Some photons, they say, have traveled 46-47 billion light-years since the Big Bang. Now how did they do that in just 13.8 billion years? The answer, say the physicist-philosophers, is that things aren’t moving away from each other so much as that the space between them is expanding. Really!

How can the universe be 93 billion light-years across if it is only 13.8 billion years old? Light hasn’t had enough time to travel that far…? Ultimately, understanding this facet of physics is the key to understanding what lies beyond the edge of the observable universe and whether we could ever get there. 

To break this down, according to special relativity, objects that are close together cannot move faster than the speed of light with respect to one another; however, there is no such law for objects that are extremely distant from one another when the space between them is, itself, expanding. In short, it’s not that objects are traveling faster than the speed of light, but that the space between objects is expanding, causing them to fly away from each other at amazing speeds.

Ultimately, this means that we could only reach the edge of the observable universe if we develop a method of transport that allows us to either 1) Travel faster than the speed of light (something which most physicists think is impossible) 2) Transcend spacetime (by using wormholes or warp drive, which most physicists also think is impossible).

The reality, I think, is that human cognition is limited. I reject the converse, that human cognition is unlimited, because, if it was, we would not have imponderable questions. Stephen Hawking has often said that “outside the universe” makes no sense, because if the universe came from nothing and brought everything into existence, then asking what lies beyond the universe is an invalid question. When physicists invoke dark energy and dark matter and, in the same breath, point out that they are unknown and undetectable, then it follows that human understanding is incomplete because of the limits to human cognition.

If human cognition is limited, whether at the level we have reached or ten times that level, our understanding of the universe around us is, and will be – and must be – also limited. We will always have a “conceptual edge” to the universe around us corresponding to our cognitive limits. Beyod this edge lies what is “unknowable”. The edge of the real universe lies at at the furthest reaches of our cognitive abilities.

As most fish (with exceptions for flying fish and lung fish) cannot conceive of the world beyond the surface of the water, so can humans not conceive a universe beyond the “conceptual edge” defined by their cognitive ability.

We can never observe what is beyond the “observable universe” because light will never get there. But it isn’t just light that doesn’t get there. Our minds don’t reach there either. There may be a multiverse out there – or maybe not. There may be just the ultimate void being converted into space-time as our universe eats into it. Or maybe there is The Restaurant at the End of the Universe awaiting the intrepid few who get there. Or maybe there is a Thing with a long white beard observing us to see if any human-fish manage to leap through the “edge of the universe”.


Humanity’s existential threats (sans alarmism)

July 13, 2017

Many so-called “scientists” indulge in phony-science which is entirely geared to winning funding. Alarmism is often misused. Such “scientists” and insurance companies cannot be trusted with risk assessments. They have a vested interest in exaggerating the risk, either to get more funding or to increase the sale of highly profitable insurance products.

(Insurance companies are expert at assessing risk. However their business is built on perceived risk being higher than actual risk. Their profits provide the evidence for how well they have succeeded both in raising perceptions of risk and in accurately predicting actual risk. “Scientific” papers authored or sponsored by insurance companies and their reports must always be taken with a large bushel of salt. Their publications are all about building up risk perceptions. They are probably very good at assessing the real risk, but that material will never get published. The risk of alarmism is multiplied when scientists are sponsored by insurance companies).

Politicians like exaggerated risk assessments where the causes of the risk are outside their control. This provides a bottomless pit of “allowable taxes”, ostensibly to “fight” against causes which are not understood and outside their control, but  provide for increased budget revenues.

Scientists, politicians and insurance companies inevitably try to arouse emotions and “fear level” to their own purposes.

The actual existential risks for humanity are a long way below what the alarmists would have us believe and need to be considered unemotionally. Risk assessment is an exercise which primarily needs common sense and which must not get mired in  “political correctness”.

The most serious existential threats facing humanity in the next 1,000 years come from the almost inevitable eruption of a super-volcano (which is overdue) and the continuing decline in global fertility which could give serious depopulation by 2100.

(I am quite happy to offer odds of 10 million to one to anybody who wishes to place money on a large asteroid impacting earth – say – within the next 5 years. The risk that the punter and I will both survive such an event. such that I have to pay out, is as close to zero as you can get).



The Ship of Theseus paradox is no paradox

July 12, 2017

A dictionary definition would define identity as the characteristics uniquely determining what makes a thing, whether living or inanimate. Consider what is necessary and sufficient to define an identity.

Inanimate things can have identity. The Great Pyramid, or the Empire State building or even that particular, nondescript boulder just there, has an identity. That particular boulder, with that volume and that physical composition and which now is located in my garden in Sweden, may have been formed when it was ejected after a volcanic eruption on Gondwanaland some 500 million years ago. Or it may have been formed 100 years ago when rocks in this region were blasted to build a road. The key point here is that this particular thing had a beginning on the time line of the universe. This beginning, this begin-time, is inextricably tied to the identity of this boulder. This identifiable boulder may have lost some mass by erosion over the years or it may have (though much less likely) grown in mass by accretion. Its mass may have changed over time and its shape and volume may have changed. Even its composition may have changed somewhat as chemical reactions with the surrounding atmosphere slowly occurred. At any given time however, the thing having identity uniquely occupies a physical space.

The Ship of Theseus (see Theseus paradox) had an identity.

The ship of Theseus, also known as Theseus’s paradox, is a thought experiment that raises the question of whether an object that has had all of its components replaced remains fundamentally the same object. The paradox is most notably recorded by Plutarch in Life of Theseus from the late first century. Plutarch asked whether a ship that had been restored by replacing every single wooden part remained the same ship.

I now borrow the concept of a control surface from fluid dynamics

In an inertial frame of reference, a control volume is a volume fixed in space or moving with constant velocity, through which the fluid (gas, or liquid) flows. The surface enclosing the control volume is referred to as the control surface.

Analogous to a control surface, I define an identity control surface. It is abstract (no mass, no thickness, no volume, no energy) but it is definable in 3-dimensional physical space at any instant of time. Unlike in fluid dynamics, this control surface does not enclose a fixed control volume, but physically encloses that which has identity. Whenever that boulder was formed, it was physically enclosed within an elastic identity control surface. The identity control surface is dynamic, elastic and permeable. It is not however fixed in space along the time axis. Its permeability allows the flow of material in both directions, but the integrity of the identity within is not compromised as long as the flow is small relative to the material enclosed. The elastic identity control surface maintains the identity enclosed as it accommodates gradual growth or a shrinkage of the enclosed physical material. The dynamic ability of the identity control surface maintains the continuity over time of the identity enclosed. An identity control surface may be embedded within another identity control surface as would happen if our boulder was used in a building which had its own identity.

This now gives me the two characteristics necessary to define identity. A thing has an identity if it has:

  1. an identity control surface which is physically definable at any instant of time, and
  2. a discrete beginning for that identity control surface on the time line of the universe (a history)

Both are necessary and are together sufficient to define the identity of an inanimate thing. The Great Pyramid and the Empire State Building comply. Their identities will end when the identity control surface is breached sufficiently to create a death on the time line of the universe.

With an identifiable identity control surface and an identified begin-time, Theseus’s ship no longer presents a paradox. As long as the replacements to the ship are small relative to the whole, its identity continues. Even if 100% of the original ship’s timbers are eventually replaced it retains its identity. However another ship gradually built up from the original (discarded) timbers would have a new beginning and a new identity surface and a new identity. Note that each timber as it was discarded would no longer be a part of identity that was Theseus’s Ship. The rebuilt ship would be a reconstruction, albeit with the original materials, of Theseus’s ship but it could never have the identity of Theseus’s ship. There is no ambiguity about identity.

It seems to me that these two characteristics would also be necessary and sufficient to define the identity not only of inanimate things but also of all living things including humans.

For all living things the identity control surface would come into being when the unique genetic make up of that entity was established. For a tree it would enclose the seed or enclose the fertilised egg for a chicken or for a human. For humans, conception or the point at which a fertilised egg embeds itself in the uterus, would seem to be appropriate as the begin-time of that identity. Initially the newly created fetus identity would be enclosed within the identity control surface of the mother and would separate at birth. As humans grow, the elastic identity control surface expands to accommodate that growth. At any time this control surface can be physically defined. The identity within remains continuous, from its begin-time till that identity control surface ceases to exist (and of course that could be some little time after death). Suppose bodies could be put into cryo-storage. Mr. X’s frozen corpse would retains its identity (as Mr. X’s body), even if Mr. X was long since dead, until decomposition destroyed the identity control surface. There is no contradiction here. The fact of being alive or not is then merely a characteristic of the identity.

The brain is not then necessary for an identity to exist. After a brain transplant – if such was possible – the identity continuing would that of the person receiving the brain. Neither is a soul a necessary condition for an identity though that does not say anything about whether a soul exists or not. The identity of each living thing, and that includes the 7 billion humans on the planet, is each uniquely characterised by its identity control surface and its begin-time. This does not address what makes a living thing human, and that would surely involve the brain and whatever one may define as being soul.

There have been suggestions that identity is virtual and based on information (Budimir Zdravkovic in The Oxford Philosopher):

….. when an entire individual is cloned; not just their DNA but their memories and experiences, too. If we assume that a person’s memory and experience is just information stored in the human brain (and the rest of the human nervous system) then in theory it should be possible to completely clone an individual with all his or her experiences, habits and memories included, providing we can reconstruct their body and nervous system.

The concept of complete human cloning is very much in line with the idea that biological identity consists in virtual information as opposed to material constitution. Since information is virtual, a person can be reconstructed eons after his death and still continue to live his life. The person’s identity becomes a function of all the information stored in his DNA, brain, and the rest of the body. After we have sufficient knowledge of the entire human brain and nervous system, in principle we ought to be able to achieve immortality via this complete human cloning.

But this is about creating replicas and not really about identity. You may be able to create an identical, cloned human, but the clone would have a different begin-time and a different identity control surface. A clone might be identical to an original but would have a completely different identity. The clone and the original would have both different begin-times and different identity control surfaces. As identical twins also have completely different identities. Even if their begin-times are identical, they occupy separated physical spaces and different identity control surfaces.

So, the reconstruction of Theseus’s ship would give rise to a new identity with a different identity control surface and a different begin-time.



Logic is discovered, language is invented

July 9, 2017

Logic is inherent in the universe. It is not a creation of man and is not dependent on observation or what kind of brain perceives the universe.

The laws of logic are taken to be unchanging over space and time. Logic now, is as logic was, and as logic will always be. Logic here, is as logic is there and everywhere.

Language, however, is invented. All languages (including mathematics or chemical notation or Boolean algebra or …..) must have a structure which is compliant with the logic of the universe it is used to describe. We perceive a logic in the universe and express it through the inbuilt logic of our language(s). We use the one to describe the other and they are both the same.

How not?


Nuclear weapons are necessary to avoid another Hitler

July 8, 2017

Yesterday the UN again demonstrated its uselessness. More, it demonstrated, again that majorities are very often wrong and can be just plain stupid.

Countries without nuclear weapons voted among themselves that countries with nuclear weapons should not have them. The stupid voting among themselves that the more intelligent should not be so intelligent.

The UN adopted a global treaty banning nuclear weapons. Only 124 nations of 193 participated. The treaty was adopted by a vote of 122 countries in favor with one NATO member, the Netherlands, voting against and with Singapore abstaining.

The stupidity of the resolution and the vote lies in that neither those who have nuclear weapons, nor those who have experienced a nuclear strike, even participated.


  1. None of the nine countries that possess nuclear weapons — the United States, Russia, UK, China, France, India, Pakistan, North Korea and Israel — took part in the negotiations or the vote.
  2.  Even Japan — the only country to have suffered atomic attacks, in 1945 — boycotted the talks and the vote.
  3. The only NATO country to participate, the Netherlands, voted against.
  4. The other NATO countries not participating were Belgium, Bulgaria, Canada, Czech Republic, Denmark, Estonia, France, Germany, Greece, Hungary, Iceland, Italy, Latvia, Lithuania, Luxembourg, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Turkey, United Kingdom, United States.

The UN is good at sanctimonious, feel-good resolutions which are “full of sound and fury” but “signifying nothing”. It is, in fact, the presence of nuclear weapons which has put a cap on the number of deaths by war.


During the 31 years leading up to the first atomic bomb, the world without nuclear weapons engaged in two global wars resulting in the deaths of an estimated 78 million to 95 million people, uniformed and civilian. The world wars were the hideous expression of what happens when the human tendency toward conflict hooks up with the violent possibilities of the industrial age. The version of this story we are most familiar with is the Nazi death machinery, and we are often tempted to think that if Hitler had not happened, we would never have encountered assembly-line murder.

…… As bad as they are, nukes have been instrumental in reversing the long, seemingly inexorable trend in modernity toward deadlier and deadlier conflicts. If the Nobel Committee ever wants to honor the force that has done the most over the past 60 years to end industrial-scale war, its members will award a Peace Prize to the bomb.

Nuclear weapons cannot be uninvented.

The simple fact is that it is the existence of nuclear weapons which has prevented the blood-letting of WW1 and WW2 from happening again.

And which prevents another Hitler from appearing. And which will prevent Kim Jong-un from ever becoming another Hitler.


Science (and the gods) rely equally on magic

July 3, 2017

The fundamental assumptions of science can be written in various ways but, for me, seem to boil down to four:

  1. The Universe exists
  2. Laws of nature (science) exist
  3. All phenomena are constrained to obey the laws of nature (science)
  4. The laws of nature (science) apply everywhere in the universe

The laws of nature are such that compliance with these laws is inbuilt. If there is any non-compliance it is not a law of nature. If compliance is all that we observe then it is a law of nature. But why the laws are what they are are usually beyond explanation.

Assumptions are not amenable to further question. You could apply an “if” to them or question “why” the assumption is true, but that is futile for there are no answers. They are just taken as self-evident and the starting point of rational thought. They are never, in themselves, self-explanatory except in the trivial form. (Assume that 1+1=2. Therefore 2+2=4 and that proves that 1+1=2).

I apply the word “magic” to all that is inexplicable. And all the fundamental laws of nature (science) are built on a foundation of inexplicable magic. How many fundamental particles exist and why? It’s magic. If the laws of science only apply after the Big Bang but don’t apply at the Big Bang singularity itself, what laws did? It’s magic. If the laws apply to a supernova but not inside a black hole, it’s magic. (Never mind that a black hole seems to be a part of the universe where the laws of science do not apply which violates the assumption that the universe is homogeneous and isotropic (Assumption 4 above). Why are there 4 – and only 4 – fundamental forces in nature? It’s magic. How did time begin? It’s magic. Can empty space exist without even the property of dimensions? It’s magic. Can time be a dimension and not have negative values? It’s magic. Dark energy and dark matter are merely labels invoking magic. All science which relies on fundamental assumptions is ultimately built upon and dependent upon a set of inexplicable, fundamental statements. They are just magic.

A fundamental flaw with the claim of physics, that all of history up to just after the Big Bang is explainable by the laws of science, must also mean that all of the future is also fixed and determined by the laws of science applied to conditions now. What will happen was therefore fixed for all time by the Big Bang itself. And that, too, is indistinguishable from magic.

Religions do not just rely on magic, they claim the magic for their gods. Modern, “with-it” religions, which try to be “compatible” with the latest knowledge discovered by science, merely claim that their God(s) pushed the button which caused the Big Bang. That my God is greater than your God is magic. That there is a life after death, or reincarnation, or rebirth or an ultimate state of grace is also just magic.

Shiva, Kali, Jesus, Allah, nirvana, dark energy, dark matter and the Big Bang singularity are all labels for different facets of magic.

Magic, by any other name, is just as inexplicable.


In the galaxy of my childhood

June 30, 2017

Long away and far ago, in the galaxy of my childhood, in a space-time continuum that has ceased to be:

  • Nothing was impossible,
  • Banks were known to handle cash,
  • customers were always right,
  • shop-keepers thanked you for your custom,
  • restaurants were happy for you to eat and dawdle,
  • the milkman brought the cow around every morning and evening to be milked,
  • coffee beans were roasted and ground every morning for the day’s consumption,
  • if it wasn’t raining it was hot,
  • if it wasn’t snowing it was cold,
  • ice cream and chocolate bars came once a week,
  • cakes were for birthdays,
  • a girl could be a tomboy and remain a girl,
  • scientists were skeptical,
  • the postman was always on time,
  • extreme weather was just extreme weather, 
  • newspapers told the truth, and
  • everything was possible



June 29, 2017

It is one of the worst feelings one can experience. To have reality intrude rudely on illusions one has cherished.

And the worst of the worst is when it is another person who is the disillusionment. When somebody turns out to be not quite what they seem to be.


When acquaintances pass away

June 28, 2017

The bulk of those we “know” are acquaintances and they may number from several hundred and up to a few thousand.

If the Dunbar Number postulation is correct, we can have strong, stable, close relationships with about 150 people (minimum about 50 and maximum about 250). We  can also “feel” strong, one-way relationships with a few public figures we may never have met, and who may not even be aware of our existence (musicians, actors, politicians ….).

When somebody close passes away the measure of our grief and our reactions is dominated primarily by the closeness of the relationship and then by the circumstances surrounding the death. This has probably been much the same for humans through most of history. However it is our reaction to the passing away of acquaintances which may say more about our changing attitudes to life and death.

I am of an age now where hardly a week goes by without the passing away of an acquaintance. I am also of an age where new acquaintances come slowly. So my circle of acquaintances is beginning to reduce. Trying to observe myself, I would generalise my reactions to the death of an acquaintance as follows:

  • Less than 50 years old : Futility, cruel, tragically young
  • In their 50’s                   : Sorrow, regret, before their time
  • In their 60’s                   : Sadness, misfortune, not very old
  • In their 70’s                   : Regret, it happens, a good innings
  • In their 80’s                   : Acceptance, acceptance, acceptance
  • In their 90’s                   : Acceptance, celebration, a long span
  • In their 100’s                 : Wow! Was he/she still alive?

Of course the circumstances of a death also play some part in the reaction  – but not so much, it seems, once an acquaintance has passed 80. The same kind of tragic accident which takes the life of a 50 year old, seems not so tragic when an 80 year old is the victim. A few months ago a good acquaintance died in his 50’s following a bicycle accident, and it all seemed such a terrible waste. About a year ago an 83 year old acquaintance also died following a bicycle accident, but his death did not seem as tragic, and even included a hint of “what on earth was he doing on a bicycle at that age?”

I suppose it is because the probability of an 80 year old dying is so much higher than that of a 50 year old. Our sense of regret and loss reduces as the probability of death increases. The circumstances surrounding the death seem less important.

At 50 the probability of death is about 1: 300 but at the age of 80 this has increased to 1:20.

UK data image bandolier

Our reactions, I conclude, are probably strongly influenced by the probability of death of that acquaintance. As longevity changes, the probability of death changes, and our reactions follow suit.



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