From extropians-request@extropy.org Sat Dec 10 09:03:56 1994 Return-Path: extropians-request@extropy.org Received: from usc.edu (usc.edu [128.125.253.136]) by chaph.usc.edu (8.6.8.1/8.6.4) with SMTP id JAA22133 for ; Sat, 10 Dec 1994 09:03:53 -0800 Received: from news.panix.com by usc.edu (4.1/SMI-3.0DEV3-USC+3.1) id AA02412; Sat, 10 Dec 94 09:03:33 PST Received: (from exi@localhost) by news.panix.com (8.6.9/8.6.9) id MAA01005; Sat, 10 Dec 1994 12:03:21 -0500 Date: Sat, 10 Dec 1994 12:03:21 -0500 Message-Id: <199412101703.MAA01005@news.panix.com> To: Extropians@extropy.org From: Extropians@extropy.org Subject: Extropians Digest #94-12-405 - #94-12-409 X-Extropian-Date: December 10, 374 P.N.O. [12:02:35 UTC] Reply-To: extropians@extropy.org X-Mailer: MailWeir 1.0 Status: RO Extropians Digest Sat, 10 Dec 94 Volume 94 : Issue 343 Today's Topics: brave new mind [1 msgs] ETHICS: "Sleeping" for success & virtue [1 msgs] SING: Are we still evolving? [2 msgs] Smart Liens [1 msgs] Administrivia: Note: I have increased the frequency of the digests to four times a day. The digests used to be processed at 5am and 5pm, but this was too infrequent for the current bandwidth. Now digests are sent every six hours: Midnight, 6am, 12pm, and 6pm. If you experience delays in getting digests, try setting your digest size smaller such as 20k. You can do this by addressing a message to extropians@extropy.org with the body of the message as ::digest size 20 -Ray Approximate Size: 27778 bytes. ---------------------------------------------------------------------- From: vincek@intergalact.com (Vince Kerchner) Date: Sat, 10 Dec 1994 01:39:26 -0800 Subject: [#94-12-405] SING: Are we still evolving? pavel@PARK.bu.edu (Paul Cisek) sez: >The 20 amino acid code has remain unchanged >at least since the development of the cell-membrane Yes, this seems to be true. So, the time necessary to evolve new amino acids may be "quite some time indeed". >One theory I've heard suggests >that the code itself was a "frozen accident" This makes sense. I see no evidence, neither from an informational nor a thermodynamic standpoint, for one DNA->AA map to be any better than any other, especially given the many autonomous repair mechanisms (including degenerative nucleotide reamination) which exist for DNA error correction. The current map does appear to be stable, in an active sense. This does not mean that it will never change, only that the activation energy necessary to induce such a change (and a concomitant change in the support system of polymerases, etc...) must be very great. The fact that all eucaryotes seem to share the same map strongly suggests a single common ancestor to virtually all life on Earth. If one subscribes to the endosymbiont theory of eucaryotic evolution, I can well imagine the proverbial "gulp" which formed the first cell nucleus, and which may have serendipitously frozen the genetic code we have today. >Originally, a three nucleotide codon was natural for reasons of symmetry, >but only the second base pair was used to specify an amino acid. Thus, >the original code only included 4 amino acids (glycine, alanine, valine, >and aspartic acid seem like likely candidates). Afterward, this code >differentiated toward specificity of the first bp position, and then >toward that of the third. You're correct in pointing out that the current map contains less than three "quads" of information. The simplest explanation for this is probably the correct one: 2 bases, yielding only 4 x 4, or 16, combinations for different amino acids, are not enough to provide the diversity in protein function we see today, while 3 full bases, yielding 4 x 4 x 4, or 64, combinations, are superfluous. As you also point out, the evolutionary tendency has been to make more and more use of the information in all three bases, so that it is not unreasonable to expect that at some time in the (possibly distant) future, all three bases will be fully coded, and that our proteins will consist of more than 20 different amino acids. It is probably unlikely, however, that more than 3 bases will ever be used in the map, since that would imply very substantial changes to tRNA and ribosomal architecture. I can think of 2 additional reasons why 3 bases might currently code for AA's: 1. In very fault-tolerant systems, three subsystems are often used to determine overall behavior. The rationale is that while two sub- systems might disagree, a third can cast the deciding vote. 2. The selection of specific tRNA's from mRNA sequences is a matter of 3-dimensional conformation. With only two points of attachment, there is an unaccounted-for degree of freedom in tRNA binding about such an axis. Three non-colinear points of attachment unambiguously determine tRNA position and orientation, and contribute to system rigidity during the formation of the peptide bond. There is, however, currently still some steric freedom ("wobble") to the tRNA-mRNA attachment, which may eventually become more stable. >The >space of all possible proteins in about as close to infinite as anything >you can think of: 4^1000000000 is a big number Yes, that's pretty big. However, the evolutionary information content, and target of biochemical selective pressures, of an organism is its DNA, not its protein set. >Survival pressures may have been >relaxed, but sexual selection still continues Sex certainly plays a very large part in evolution. Sex does not change the underlying genetic material, but it does cause it to be rearranged substantially. The evolution of a diplobiontic lifecycle (i.e. homologous chromosome pairs), and especially of the diploid-stage organism as the primary target of selective pressure (rather than the gametes), gives rise to the existence and importance of recessive and dominant genes. In general, the chromosomal crossover that occurs during meiosis allows genetic configuration space to be searched in much larger steps than are afforded by the relatively small changes caused by mutation. This is equivalent to a global search process in fitness-function optimization, as opposed to the more local search provided by mutation. Without sex, there would be considerably less genetic diversity in our species, and many potentially beneficial adaptive traits would not be discovered. CurtAdams@aol.com sez: >Mutations >tend to kill individuals by changing so many proteins at once I'm not sure this is true. Given the redundency of the genetic code, and the fact that changes to AA sequences far from the active sites of enzymes may have little or no change on the conformation of the enzyme, it might be possible for mutations to gradually accumulate over time without being reflected in the phenotype. At some point, a critical AA change will eventually occur which does alter enzyme shape and function, and this change will be reflected as an observable difference in the organism. This may be the basis for the punctuated equilibrium of macroscopic evolution. Mutations may be continuously happening to us, without our knowledge. As you suggest, in general, random mutations are not beneficial (any more than random changes to a computer program are beneficial), since they act to disturb what was once a stable protein configuration. Benign mutations probably must accumulate over time, so as to overcome the local activation energy of the micro-evolutionary landscape without killing the organism and its descendents, while moving the gene sequence to a new optimal point in gene space. >Of course, we could change the map artificially. This is one of the key technological goals of Extropian self-transformation. >A complete change in the >map, with associated changes to transcribed proteins and auxiliary item like >transfer RNA, would create a nearly identical creature with a completely >different DNA. For this to happen, the new map would still have to specify the old sequence of AA's in translated proteins, so that protein conformation and function would be the same. The key items in this process would be the new tRNA->AA mappings. Other than that, I see no reason why this couldn't happen. >Said creature would have one very substantial advantage - >current viruses could not affect it. It also could not breed or swap genes >with any existing earth species. Maybe, and maybe not. If the only thing to change was the genetic code, it would still be possible for a retrovirus to insert its DNA into a chromosome of an "altered-code" cell. This viral DNA would still be replicated along with the DNA of the host. Assuming that the viral sequence was transcribed, without regard for function, along with indigenous exons, it would be up to the new tRNA->AA mapping to halt the infection process. Such viruses could continue to lie dormant, indefinitely. I don't necessarily see that there would be any pre-zygotic barriers to reproduction between aliens and terrestrial species. There may not be any post-zygotic ones either. Are there any biochemical functions which require the presence of both homologous chromosome pairs in order to function? I think there are at least human diseases (especially sex-related) which are the result of a chromosomal deficiency. If there are not, then each adult organism would be essentially haploid, and the foreign DNA would make no contribution to protein synthesis. Foreign DNA would, however, continue to be replicated, and could be passed on to progeny as part of meiosis. Oliver Seiler sez: >I also suppose their are many other genetic pressures - cuteness >and vulnerability seem to make a lot of people band together to save >animals. I've noticed this phenomenon in the movies, especially in Steven Spielberg films: all the "good" aliens, dinosaurs, etc, have cute faces with really big eyes. Obviously an adaptive trait. :-) It is interesting to note, while we're on the subject, that this evening's episode of "The X Files" concerned a group of teenagers who were being surreptitiously inoculated with alien immunoglobulins (antibodies). According to the lab reports, these proteins did not contain terrestrial amino acids. The show didn't say what kind of immunoglobulin, or for what antigen it might have been targeted. They did say, however, that the same compound had been injected into beef and milk cattle, which had then been shipped to parts unknown. A good time to become a vegan, perhaps? ;-) --Vince * * * * * * * * * * * * * * * * * * * * * * * * * * Copyright Vince Kerchner, 1994. "We want information." Intergalactic Reality "You won't get it." vincek@intergalact.com "By hook, or by crook, we will." * * * * * * * * * * * * * * * * * * * * * * * * * * ------------------------------ From: vincek@intergalact.com (Vince Kerchner) Date: Sat, 10 Dec 1994 01:54:36 -0800 Subject: [#94-12-406] ETHICS: "Sleeping" for success & virtue Max More sez: >Vince seems to think that merely expressing my view amounts >to "imposing it" on others. :-( Huh? Sorry if you got that impression. In general, I agree pretty much with the viewpoints you espoused in your first post on this subject. I just don't have any interest in imposing my personal ethic on anyone else (i.e. I wouldn't judge another person by the same ethical standard I apply to myself), and I tend to be a little overcritical of anyone else who might be doing this. Perhaps this is a contradiction I need to be a little more careful of. --Vince * * * * * * * * * * * * * * * * * * * * * * * * * * Copyright Vince Kerchner, 1994. "We want information." Intergalactic Reality "You won't get it." vincek@intergalact.com "By hook, or by crook, we will." * * * * * * * * * * * * * * * * * * * * * * * * * * ------------------------------ From: szabo@netcom.com (Nick Szabo) Date: Sat, 10 Dec 1994 03:24:52 -0800 (PST) Subject: [#94-12-407] Smart Liens T. David Burns: > My PA is agreeing with me that anyone who lends my > corporation money does not have the option of grabbing all my stuff if the > corporation defaults on the loan. My liability is limited. Of course, no wise bank will lend you more than your securely liened collateral plus some conservative function of your reputation for payment in full and on time. Your liability is limited, but so is your credit. The potential for other actions you might take that cause liability, such as damage to others' persons or property, also need to be limited. More on that later. Many agents, especially new entrants, may lack this reputation capital, and will thus need to be able to share their property with the bank via secure liens. A lien is, in a practical sense, a method of sharing a piece of property between the "owner of record" and a "lienholder", instead of the property having strictly one owner. Liens are used in many large credit transactions, such as auto loans, mortgages, farm loans, etc. They are enforced by the jurisdiction specified in the contract; usually this enforcement is done by the government and subsidized by the taxpayers rather than paid for by the contracting parties. (In fact this usually is the case with contracts and property rights in general, the enforcement clause is an implicit government subsidy). One way to implement a lien without governments is via co-signing with your PA (as long as the PA has a good credit rating and the contractual right to take appropriate action against you). Another way is with what I call a "smart lien". A smart lien is an electronic, cryptographic system whereby both parties need to identify themselves to the property for that property to function properly. For example, a smart lien on a piece of real estate would control the utilities (electric, water, etc.), shutting them off if either the lienholder or the owner so choose, or if the system is tampered with to try to disable the lien. As is the case today, credit problems will usually be solved by artfully written, menacing dunning letters and dings to one's credit rating long before the lien needs to be invoked. If PAs bear ultimate responsibility for the criminal activities of their customers, or need to insure lack of defection or future payments on the part of customers, they may in turn ask for liens against their customers, either in with contractual terms allowing arrest of customers under certain conditions (eg if they commit acts specified as criminal by the PA contract) or (more likely for mobile world-traveling and virtual pseudonymous customers) smart liens against resaleable assets such as bank accounts and investment portfolios. Smart liens over information, such as digital bearer securities, can be implemented via secret-splitting (two or more keys required to unlock the encryption). The "ultimate lien" would be a kind of cardiac anti-pacemaker controlled by the lienholder. PA customers would likely reject PAs with such an outrageous requirement. However, one can imagine PA leaders themselves required to have ultimate liens, controlled by an N-out-of-M voting system of their customers and/or cross-contracted foreign PAs, as a hedge against their power. Other important areas of liability include consumer liability and property damage (including pollution). There need to mechanisms so that, for example, pollution damage to others' persons or property can be assessed, and liens should exist so that the polluter can be properly charged and the victims paid. Where pollution is quantifiable, as with SO2 emissions, markets can be set up to trade emission rights. The PAs would have liens in place to monitor their customer's emissions and assess fees where emission rights have been exceeded. Alas, there are some dangers where maximum damage could far surpass any liens. A good rule of thumb here is that if the risk is against a third party, and it cannot be liened or insured against, then PAs should not allow it to be taken. PAs that allow their customers to take such risks against non-PA parties would ruin their credit rating. One example of such a risk is building a nuclear plant for which no insurance company is willing to submit liability coverage. If a plant is safe, presumably one should be able to convince a good insurance company to cover its potential to damage others' property. Smart liens are one element of smart contracts. Smart contracts will to replace, and even protect against, lawyers, politicians, and violent enforcement in many business and social interactions, as well as to design lucrative new free-market institutions. See my essay "Smart Contracts", at ftp://ftp.netcom.com/ for more on designing jurisdiction-free institutions around smart contracts. Nick Szabo szabo@netcom.com ------------------------------ From: nancy@genie.slhs.udel.edu Date: Sat, 10 Dec 94 12:32:02 GMT Subject: [#94-12-408] SING: Are we still evolving? Oliver Seiler writes about human-caused evolutionary pressures on animals. I've heard that there's a variant oppossum that runs instead of freezing when frightened--it's a better reaction for dealing with highways. I don't know if this is happening, but I would think that all those many years of trophy hunting is selecting for smaller, smarter deer. I don't think that environmentalism has been around long enough to select for "cuteness", but it would be interesting if that happens, since I think that cuteness=neoteny and might go with increased intelligence. Nancy Lebovitz ------------------------------ From: dasher@netcom.com (Anton Sherwood) Date: Sat, 10 Dec 1994 04:53:06 -0800 Subject: [#94-12-409] brave new mind Mark Fischer: >Considering that the human brain is a hack, (With 3 distinct >layers, reptilian, mammalian, and the most recently evolved, >consciousness providing layer), . . . Is the last a distinct layer, or just an over-development of the second? Phil Goetz: > I ask: Is the mind an ear of corn or an onion? > Start peeling away sources of irrational behavior: testosterone, > PMS, pain, discomfort, tiredness, anger, sorrow,... > Will you eventually reach some golden Platonic mind at the center, > or will there be nothing left when you peel away the last layer? The process is self-limiting: long before you peel away everything, you'll lose interest in the project. Jordan Sparks contends: > . . . . Now, if you increase the speed of the human's > mind (say, double it), the VR has to keep up by doubling its speed. > The relationship between the speed of the VR and the human brain is > a constant, no matter what the factor of increase in speed up. . . . This problem goes away if you upload as a software simulation, time-sharing with the VR in the same hardware. If you as the occupant control the ratio of time-slices spent on yourself to time-slices spent on VR, you can trade off realism for mental speedup. One limitation on meat that hasn't been mentioned in this thread is the size of the skull (or, if you prefer, the size of the adult pelvis). Nano-logic will presumably be smaller than the old-fashioned kind. So what I want my new brain to do first is _grow_ as it did when I was a child. A growing brain is just the thing for learning new techniques. (I haven't acquired another language since puberty.) Anton Sherwood *\\* +1 415 267 0685 *\\* DASher@netcom.com ------------------------------ End of Extropians Digest V94 #343 *********************************