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28/01/2020

Daniel C. Dennett – “From Bacteria to Bach and Back” (II)


   “Could something as intellectually sophisticated as a digital computer, for instance, ever evolve by bottom-up natural selection? This is very hard to imagine or even to take seriously, and this has inspired some thinkers to conclude that since evolution couldn’t create a computer (or a computer program to run on it), human minds must not be products of natural selection alone, and the aspirations of Artificial Intelligence must be forlorn”.

“How could a slow, mindless process build a thing that could build a thing that a slow mindless process couldn’t build on its own? If this question seems to you to be unanswerable, a rhetorical question only, you are still in thrall to the spell Darwin broke, still unable to adopt Darwin’s “strange inversion of reasoning.” Now we can see how strange and radical it is: a process with no Intelligent Designer can create intelligent designers who can then design things that permit us to understand how a process with no Intelligent Designer can create intelligent designers who can then design things”.

“The idea that every organism has its ontology (in the elevator sense) was prefigured in Jakob von Uexküll’s (1934) concept of the organism’s Umwelt, the behavioral environment that consists of all the things that matter to its well-being”.

“Gregorian creatures, named in honor of Richard Gregory, the psychologist who emphasized the role of thinking tools in providing thinkers with what he called “potential intelligence.” The Gregorian creature’s Umwelt is well stocked with thinking tools, both abstract and concrete: arithmetic and democracy and double-blind studies, and microscopes, maps, and computers. A bird in a cage may see as many words every day (on newspaper lining the cage floor) as a human being does, but the words are not thinking tools in the bird’s Umwelt”.

   “ The task of a nervous system is to extract information from the environment to use in modulating or guiding successful behavior”.

“Shannon idealized and simplified the task of moving semantic information from point A to point B by breaking the task down into a sender and a receiver (two rational agents, note) with a channel between them and a preestablished or agreed-upon code, the alphabet or ensemble of permissible signals. The channel was susceptible to noise (which was anything that interfered with transmission, degrading the signal), and the task was to achieve reliable transmission that could overcome the noise. Some of the designs that accomplish this were already well understood when Shannon devised his theory, such as the Able Baker Charlie Dog Easy Fox … system of alphabet letters, used by the US Navy (superseded by the Alpha Bravo Charlie Delta Echo Foxtrot … system, the NATO Phonetic Alphabet in 1955) in voice radio transmission to minimize the confusion between the rhyming letters”.

“Robert Anton Wilson, an author of science fiction and writer on science, proposed the Jesus unit, defined as the amount of (scientific) information known during the lifetime of Jesus”.

“There was exactly one Jesus of scientific information in AD 30, by definition, an amount that didn’t double (according to Wilson) until the Renaissance 1,500 years later. By 1750 it doubled again to 4 Jesus, and doubled to 8 Jesus in 1900. By 1964 there were 64 Jesus, and Lord knows how many Jesus (Jesuses?) have accumulated in the meantime”.

“Consider a less fantastical possibility than trees with eyes: brilliant autumn foliage. Is it an adaptation in trees? If so, what is it good for? It is commonly understood to be not an adaptation but merely a functionless byproduct of the chemical changes that occur in deciduous leaves when they die. The leaves stop making chlorophyll when the sunlight diminishes, and as the chlorophyll decomposes, other chemicals present in the leaves—carotenoids, flavonoids, anthocyanins—emerge to reflect the remaining light”.

“Evolution depends on the existence of high-fidelity copying but not perfect copying, since mutations (copying errors) are the ultimate source of all novelty. Digital copying technology is perfect, for all practical purposes: if you copy a copy of a copy of a copy … of a Word file, it will be letter-for-letter identical to the original file. Don’t expect mutations to accumulate, for better or for worse. DNA copies itself almost perfectly, but without its very occasional errors (not one in a billion nucleotides), evolution would grind to a halt”.

“When life began, it was anaerobic (it didn’t require oxygen), and the atmosphere was almost oxygen-free, but once photosynthesis evolved, living things began pumping oxygen (in the form of CO2 and O2) into the atmosphere. This took several billion years, and some of the O2 in the upper atmosphere was turned into O3, or ozone, and without it, deadly radiation would reach the Earth’s surface and make our kind of life impossible. The oxygen level 600 million years ago was only 10% of its current level, so although the change is imperceptibly slow, it is dramatic over time”.

“Engineers have managed to create the technology to print microscopic computer circuits with millions of identical flip-flops each reliably storing a 0 or 1 until ordered (from on high) to “flip the bit.” These are the ultimate moving parts of a computer and they have no individuality, no idiosyncrasies at all. Neurons, in contrast, are all different; they come in a variety of quite clearly defined structural types—pyramidal, basket, spindle, and so on—but even within types, no two neurons are exactly alike”.

25/01/2020

Daniel C. Dennett – “From Bacteria to Bach and Back”


   “Even the simplest bacterial cells have a sort of nervous system composed of chemical networks of exquisite efficiency and elegance. But how could just the right combination of membranes and do-loops ever arise in the prebiotic world? “Not in a million years!” some say. Fair enough, but then how about once in a hundred million years? It only has to happen once to ignite the fuse of reproduction”

“The termite castle and Gaudí’s La Sagrada Familia are very similar in shape but utterly different in genesis and construction. There are reasons for the structures and shapes of the termite castle, but they are not represented by any of the termites who constructed it. There is no Architect Termite who planned the structure, nor do any individual termites have the slightest clue about why they build the way they do. This is competence without comprehension, about which more later. There are also reasons for the structures and shapes of Gaudí’s masterpiece, but they are (in the main) Gaudí’s reasons. Gaudí had reasons for the shapes he ordered created; there are reasons for the shapes created by the termites, but the termites didn’t have those reasons. There are reasons why trees spread their branches, but they are not in any strong sense the trees’ reasons. Sponges do things for reasons, bacteria do things for reasons; even viruses do things for reasons. But they don’t have the reasons; they don’t need to have the reasons”.

“Endosymbiosis is a crane; it lifted simple single cells into a realm of much complexity, where multicellular life could take off. Sex is a crane; it permitted gene pools to be stirred up, and thus much more effectively sampled by the blind trial-and-error processes of natural selection. Language and culture are cranes, evolved novelties that opened up vast spaces of possibility to be explored by ever more intelligent (but not miraculously intelligent) designers. Without the addition of language and culture to the arsenal of R&D tools available to evolution, there wouldn’t be glow-in-the-dark tobacco plants with firefly genes in them”.

“Both Darwin and Turing claim to have discovered something truly unsettling to a human mind—competence without comprehension. Beverley expressed his outrage with gusto: the very idea of creative skill without intelligence!”.

   “Even bacteria are good at staying alive, making the right moves, and keeping track of the things that matter most to them; and trees and mushrooms are equally clever, or, more precisely, cleverly designed to make the right moves at the right time. They all have elevator-type “minds,” not elevated minds like ours.16 They don’t need minds like ours. And their elevator-minds are—must be—the products of an R&D process of trial and error that gradually structured their internal machinery to move from state to state in a way highly likely—not guaranteed—to serve their limited but vital interests”.

“we should take the same line with bacteria, and with trees and mushrooms. They exhibit impressive competence at staying-alive-in-their-limited-niches, thanks to the well-designed machinery they carry with them, thanks to their genes. That machinery was designed by the R&D process of natural selection, however, so there is nothing anywhere at any time in that R&D history that represents the rationales of either the larger functions of whole systems or component functions of their parts the way comments and labels represent these functions for human designers”.

“linguists today are still thrashing around trying to write a satisfactory version of the “rule book” for speaking English, while every ten-year-old native English speaker has somehow installed and debugged a pretty good version of the executable object code for the control task of speaking and understanding the language”.

24/01/2020

Thomas Asbridge – The Crusades: “The Authoritative History of the War for the Holy Land“

Filed under: FRAGMENTE DIN CARTI SI BLOGURI — afractalus @ 12:09
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  “Notably, Pope Urban II did not invent the term ‘crusade’. The expedition he launched at Clermont was so novel, and in some ways still so embryonic in its conception, that there was no word with which it could be described. Contemporaries generally termed this ‘crusade’ simply an iter (journey) or peregrinatio (pilgrimage). It was not until the close of the twelfth century that more specific terminology developed, in the form of the word crucesignatus (one signed with the cross) for a ‘crusader’, and the eventual adoption of the French term croisade, which roughly translates as ‘the way of the cross’. For the sake of convention and clarity, historians have adopted the term ‘crusade’ for the Christian holy wars launched from 1095 onwards, but we should be aware that this lends a somewhat misleading aura of coherence and conformity to the early ‘crusades’”.

“Historians continue to dispute the numbers involved, primarily because of the unreliability of wildly inflated contemporary estimates (some of which exceed half a million people). Our best guess is that somewhere between 60,000 and 100,000 Latin Christians set off on the First Crusade, of which 7,000 to 10,000 were knights, perhaps 35,000 to 50,000 infantry troops and the remaining tens of thousands non-combatants, women and children”.

15/01/2020

Rodney Stark – „God’s Battalions „


“In 711 an army of seven to ten thousand Muslims from Morocco crossed the Mediterranean at its narrowest western point and landed on the coast of Spain at the foot of a mountain jutting out into the sea. Later this mountain was named after the Muslim commander, the Berber Tariq ibn-Ziyad, as the Rock of Tariq, hence Jabal Tariq or Gibraltar”.

 “It is true that the Qur’an forbids forced conversions. However, that recedes to an empty legalism given that many subject peoples were “free to choose” conversion as an alternative to death or enslavement. That was the usual choice presented to pagans, and often Jews and Christians also were faced with that option or with one only somewhat less extreme.39 In principle, as “People of the Book,” Jews and Christians were supposed to be tolerated and permitted to fol ow their faiths. But only under quite repressive conditions: death was (and remains) the fate of anyone who converted to either faith”.

 “In 705 the Muslim conquerors of Armenia assembled al the Christian nobles in a church and burned them to death.43 There were many similar episodes in addition to the indiscriminate slaughters of Christians noted earlier in discussions of the Muslim conquests. The first Muslim massacre of Jews occurred in Medina when Muhammad had al the local adult Jewish males (about seven hundred of them) beheaded after forcing them to dig their own graves.44 Unfortunately, massacres of Jews and Christians became increasingly common with the passage of time. For example, in the eleventh century there were many mass kil ings of Jews—more than six thousand in Morocco in 1032–1033, and at least that many murdered during two outbursts in Grenada.45 In 1570 Muslim invaders murdered tens of thousands of Christian civilians on Cyprus”.

 “Western historians have long hailed this as “a turning point in the history of mankind.”2 The Russian-born Byzantine scholar George Ostrogorsky (1902–1976) characterized the attack on Constantinople as “the fiercest which had ever been launched by the infidels against a Christian stronghold, and the Byzantine capital was the last dam left to withstand the rising Muslim tide. The fact that it held saved not only the Byzantine Empire, but the whole of European civilization.”3 Or as the distinguished historian of Byzantium Viscount John Julius Norwich put it: “Had they captured Constantinople in the seventh century rather than the fifteenth, al Europe—and America—might be Muslim today.”

 “Consider mathematics. The so-cal ed Arabic numerals were entirely of Hindu origin. Moreover, even after the splendid Hindu numbering system based on the concept of zero was published in Arabic, it was adopted only by mathematicians while other Muslims continued to use their cumbersome traditional system. Many other contributions to mathematics also have been erroneously attributed to “Arabs.” For example, Thabit ibn Qurra, noted for his many contributions to geometry and to number theory, is usual y identified as an “Arab mathematician,” but he was a member of the pagan Sabian sect”.

 “Avicenna, whom the Encyclopaedia Britannica ranks as “the most influential of al Muslim philosopher-scientists,” was a Persian. So were the famous scholars Omar Khayyám, al-Biruni, and Razi, al of whom are ranked with Avicenna. Another Persian, al-Khwarizmi, is credited as the father of algebra. Al-Uqlidisi, who introduced fractions, was a Syrian. Bakht-Ish ’ and ibn Ishaq, leading figures in “Muslim” medical knowledge, were Nestorian Christians. Masha’al ah ibn Athar , the famous astronomer and astrologer, was a Jew”.

“Even many of the most partisan Muslim historians, including the famous English convert to Islam and translator of the Qur’an Mar-maduke Pickthal (1875–1936), 28 agree that the sophisticated Muslim culture originated with the conquered populations. But what has largely been ignored is that the decline of that culture and the inability of Muslims to keep up with the West occurred because Muslim or Arab culture was largely an il usion resting on a complex mix of dhimmi cultures, and as such, it was easily lost and always vulnerable to being repressed as heretical. Hence, when in the fourteenth century Muslims in the East stamped out nearly al religious nonconformity, Muslim backwardness came to the fore”.

“Underlying the belief that the Muslims were more learned and sophisticated than the Christian West is the presumption that a society not steeped in Greek philosophy and literature was a society in the dark! Thus for the past several centuries many European writers have stressed the Arab possession of the classical writers, assuming that by having access to the advanced “wisdom” of the ancients, Islam was the much superior culture. Although medieval European scholars were far more familiar with the “classics” than was claimed, the fact is that because of the persistence of Byzantine/Greek culture in most of the conquered Arab societies, the most-educated Arabs did have greater knowledge of the work of classical Greek authors such as Plato and Aristotle”.

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