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”.

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