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December 6, 2018 - May 1, 2019
Measure A method by which a theory gives meaning to proportions and averages of infinite sets of things, such as universes.
Infinite regress A fallacy in which an argument or explanation depends on a sub-argument of the same form which purports to address essentially the same problem as the original argument.
SUMMARY
if unlimited progress really is going to happen, not only are we now at almost the very beginning of it, we always shall be.
The possibilities that lie in the future are infinite. When I say ‘It is our duty to remain optimists,’ this includes not only the openness of the future but also that which all of us contribute to it by everything we do: we are all responsible for what the future holds in store. Thus it is our duty, not to prophesy evil but, rather, to fight for a better world. Karl Popper,
Rees’s book Our Final Century, published in 2003, he came to the worrying conclusion that civilization now had only a 50 per cent chance of surviving the twenty-first century.
Rees thought it likely that civilization-destroying weapons, particularly biological ones, would soon become so easy to make that terrorist organizations, or even malevolent individuals, could not be prevented from acquiring them. He also feared accidental catastrophes, such as the escape of genetically modified micro-organisms from a laboratory, resulting in a pandemic of an incurable disease.
our own future will be shaped by knowledge that we do not yet have.
Observations are theory-laden. Given an experimental oddity, we have no way of predicting whether it will eventually be explained merely by correcting a minor parochial assumption or by revolutionizing entire sciences.
The Principle of Optimism All evils are caused by insufficient knowledge. Optimism is, in the first instance, a way of explaining failure, not prophesying success. It says that there is no fundamental barrier, no law of nature or supernatural decree, preventing progress.
SOCRATES: [with dignity] If, on occasion, I make fun of someone, it is because I hope he will help me to seek a truth that neither he nor I yet knows. I do not mock from on high, as you do. I want only to goad my fellow mortal into helping me look beyond that which is easy to see.
Posterity is all of you, my friends. What is the point of writing down things that are going to be endlessly tinkered with and improved? Rather than make a permanent record of all my misconceptions as they are at a particular instant, I would rather offer them to others in two-way debate. That way I benefit from criticism and may even make improvements myself. Whatever is valuable will survive such debates and be passed on without any effort from me. Whatever is not valuable would only make me look a fool to future generations. PLATO: If you say so, Master.
the default assumption should be that misunderstandings are ubiquitous and that neither intelligence nor the intention to be accurate is any guarantee against them.
The immediate reason is that the original sources of scientific theories are almost never good sources. How could they be? All subsequent expositions are intended to be improvements on them, and some succeed, and improvements are cumulative.
There is rarely any reason for scientists to address the obsolete problem-situations that motivated the great scientists of the past.
water at double its normal density exerts a pressure of hundreds of thousands of atmospheres.
good fictional science is hard to invent: it is a variant of real science, and real scientific knowledge is very hard to vary.
A remark about terminology: The world is the whole of physical reality. In classical (pre-quantum) physics, the world was thought to consist of one universe – something like a whole three-dimensional space for the whole of time, and all its contents. According to quantum physics, as I shall explain, the world is a much larger and more complicated object, a multiverse, which includes many such universes (among other things). And a history is a sequence of events happening to objects and possibly their identical counterparts.
knowledge, once embodied in physical form in a suitable environment, causes itself to remain so.
The vacuum, which we perceive as empty at everyday scales and even at atomic scales, is not really emptiness, but a richly structured entity known as a ‘quantum field’. Elementary particles are higher-energy configurations of this entity: ‘excitations of the vacuum’. So, for instance, the photons in a laser are configurations of the vacuum inside its ‘cavity’. When two or more such excitations with identical attributes (such as energy and spin) are present in the cavity, there is no such thing as which one was there first, nor which one will be the next to leave. There is only such a thing as
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common sense and classical physics contain the parochial error that only one history exists. This error, built into our language and conceptual framework, makes it sound odd to say that an event can be in one sense extremely unlikely and in another certain to happen. But there is nothing odd about it in reality.
Interference is the phenomenon that can provide the inhabitants of the multiverse with evidence of the existence of multiple histories in their world without allowing the histories to communicate.
If the differential effects can all be undone, then interference between those original values becomes possible again;
If a photon is introduced travelling rightwards (X) after the first mirror instead of before as shown, then it appears to emerge randomly, rightwards or downwards, from the last mirror (because then, happens there). The same is true of a photon introduced travelling downwards (Y) after the first mirror. But a photon introduced as shown in the diagram invariably emerges rightwards, never downwards. By doing the experiment repeatedly with and without detectors on the paths, one can verify that only one photon is ever present per history, because only one of those detectors is ever observed to
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histories may split into more than two – often into many trillions – each characterized by a slightly different direction of motion or difference in other physical variables of the elementary particle concerned.
the real multiverse is not ‘based on’ anything, nor is it a correction to anything. Universes, histories, particles and their instances are not referred to by quantum theory at all – any more than are planets, and human beings and their lives and loves. Those are all approximate, emergent phenomena in the multiverse.
whenever a measurement is made, all the histories but one cease to exist. The surviving one is chosen at random, with the probability of each possible outcome being equal to the total measure of all the histories in which that outcome occurs.
Its combination of vagueness, immunity from criticism, and the prestige and perceived authority of fundamental physics opened the door to countless systems of pseudo-science and quackery supposedly based on quantum theory.
Fortunately also, Einstein soon rejected positivism and became a forthright defender of realism.
Positivism degenerated into logical positivism, which held that statements not verifiable by observation are not only worthless but meaningless. This doctrine threatened to sweep away not only explanatory scientific knowledge but the whole of philosophy.
without powerful techniques of error-detection and -correction – which depend on explanatory theories – this gives rise to an instability where false results drown out the true. In the ‘hard sciences’ – which usually do good science – false results due to all sorts of errors are nevertheless common.
SUMMARY
It is a fact – often mentioned but seldom explained – that deep truth is often beautiful. Mathematicians and theoretical scientists call this form of beauty ‘elegance’.
The whole activity of skydiving is beautiful, and part of that beauty is in the very sensations that evolved to deter us from trying it. The conclusion is inescapable: that attraction is not inborn, just as the contents of a newly discovered law of physics or mathematical theorem are not inborn.
is co-evolution between the genes to coordinate mating behaviours in males and females of the same species, so genes for making flowers and giving them their shapes and colours co-evolved with genes in insects for recognizing flowers with the best nectar.
This, too, is not as different from science and mathematics as it looks: poetry and mathematics or physics share the property that they develop a language different from ordinary language in order to state things efficiently that it would be very inefficient to state in ordinary language. And both do this by constructing variants of ordinary language: one has to understand the latter first in order to understand explanations of, and in, the former.
SUMMARY
The behaviour of people in a long-lived culture is therefore determined partly by recent ideas that will soon become extinct, and partly by long-lived memes: exceptional ideas that have been accurately replicated many times in succession.
A fundamental question in the study of cultures is: what is it about a long-lived meme that gives it this exceptional ability to resist change throughout many replications? Another – central to the theme of this book – is: when such memes do change, what are the conditions under which they can change for the better?
Genes and memes are about as different as can be at the level of mechanisms, and of outcomes; they are similar only at the lowest level of explanation, where they are both replicators that embody knowledge and are therefore conditioned by the same fundamental principles that determine the conditions under which knowledge can or cannot be preserved, can or cannot improve.
classic 1956 science-fiction story ‘Jokester’, by Isaac Asimov,
memes in general: they implicitly contain information that is not known to the holders, but which nevertheless causes the holders to behave alike.
A meme exists in a brain form and a behaviour form, and each is copied to the other.
Because of the alternating physical forms of a meme, it has to survive two different, and potentially unrelated, mechanisms of selection in every generation. The brain-memory form has to cause the holder to enact the behaviour; and the behaviour form has to cause the new recipient to remember it – and to enact it.
That some memes can replicate themselves with great fidelity for many generations is a token of how much knowledge they contain.
Societies have been destroyed because some of the memes that were best at spreading through the population were bad for a society.
a substantial proportion of all evolution on our planet to date has occurred in human brains. And it has barely begun. The whole of biological evolution was but a preface to the main story of evolution, the evolution of memes.
Just as genes for the eye implicitly ‘know’ the laws of optics, so the long-lived memes of a static society implicitly possess knowledge of the human condition, and use it mercilessly to evade the defences and exploit the weaknesses of the human minds that they enslave.
Like genes, memes do not evolve to benefit the group. Nevertheless, just as gene evolution can create long-lasting organisms and confer some benefits on them, so it is not surprising that meme evolution can sometimes create static societies, cooperate to keep them static, and help them to function by embodying truths.
every society on Earth before the current Western civilization has either been static or has been destroyed within a few generations.
