Are you suggesting that we can have a prolonged period of time where proteins reproduce other proteins without DNA guiding this process? Do we see this today?
There are certainly modern examples of proteins producing other proteins, but they are very much the exception. We are much in the position of a naive observer viewing a modern auto factory. Finding that the construction of cars is heavily robotic and controlled by computers, such an observer might well conclude that the invention of the automobile must have occurred subsequent to the invention of computers and manufacturing robots, since they are so clearly fundamental to automobile manufacture. The ribosome is a sort of robotic assembly line for efficient production of the large number of proteins required by modern complex forms of life. That doesn't mean that life started that way.
Regarding the possibility of RNA being the first self-replicator I don't think that producing amino acids is a usefull precursor for that (I could be wrong, I'm going to re-read my Isaac Asimov book on genetics tonight), or at least the jump from amino acids to RNA would be much greater than the jump from amino acids to proteins.
The RNA-first idea is not the only theory. RNA has the advantage that there is potentially a simple method of reproduction. On the other hand, it's much easier to come up with ways to get spontaneous formation of polypeptides than RNA, and it is possible to envision a self-reproducing metabolism based entirely around polypeptide catalysis, with no need for nucleic acid. Once you have polypeptides around to catalyze things, it's easier to get nucleic acids. Or perhaps RNA and proteins evolved independently and eventually developed a symbiotic relationship.
You are talking about DNA that was first housed in a living organism coated with protective proteins and then fossilized in amber. I meant that you wouldn't find the stuff floating around untended in the ocean or in a pre-biotic soup
DNA is readily recovered from bodies that have been rotting in the ground for years. As I said, it is quite stable. And it might well be even more stable in a prebiotic soup, because it wouldn't have to deal with enzymes specifically designed to degrade DNA.
Not quite. There are limits to chance. There is a number which represents the number of electrons in the universe. If something has odds of 1 in that number, it is considered impossible.
Wrong. That number is not the number of electrons in the entire universe (which current astrophysical data suggests may be infinite). It is the number of electrons in the part of the universe that we can see from here, sometimes referred to as the "accessible" universe. As you look off in the distance, you look backwards in time, because light has a finite speed. So there is a maximum distance that you can see, corresponding to the time since the Big Bang. That doesn't mean that there are no electrons beyond that point; only that any light that they have emitted could not have reached us.
Evolutionists commonly quote examples similar to Darwin's finches as proof of evolution. They do not understand that these observations are explained equally well, or better, under the creationist model.
Actually, they understand that perfectly. They also understand that absolutely any result can be explained by the creationist model, because there are absolutely no limits on what an incomprehensible supernaturally omnipotent entity might choose to do. So if a result is consistent with creationism, it means nothing. On the other hand, evolution imposes a lot of limits. Creationism would allow, for example, for every single organism to have a different genetic code. Evolution requires that it be the same. So it is far more meaningful when a result can be explained by evolution than when it can be "explained" by creationism.
Many basic blocks are still missing, and you can't do much with a pile of blocks anyway.
Of course, the earliest form of life probably did not use all of the "blocks", and of course, the term "block" is just a metaphor. It can be misleading if you take it too literally, because bricks lack a fundamental capacity of the "building blocks" of life: the ability to spontaneously assemble themselves into chains under a variety of conditions, which in turn have the abilty to catalyze the assembly of other chains.
Most people think in terms of building a Lego lifeform, now that the blocks are available, but even building a "simple" lifeform from these bricks is somewhat akin to building a Gibraltar Bridge out of Lego (with all of the long ones missing and half of the existing pieces having the dots and dents the wrong way out, just to add insult to injury).
To think in terms of building even the simplest modern form of life is indeed akin to imagining that the history of bridge building began with the construction of something of the size and complexity of the Bridge of Gibraltar, using primitive tools and materials. This is a fundamental error. The fact is that there are no simple modern forms of life. The life forms that we sometimes loosely refer to as "simple" are probably more correctly regarded as "stripped down," in the sense of a modern high-performance racing car. It won't tell you much about what the first motorized vehicles looked like, or how they worked.
What some people debate is the theory that evolution is what guided life from single-celled organisms to, say, mammals. Going from evolution to the latter is a huge jump.
It is worth noting that when the theory of evolution was formulated, nobody knew anything about how inheritance worked, much less DNA, yet from the theory, one could derive the hard prediction that every organism, from microorganism to man, must use the same fundamental mechanism of inheritance. The discovery of DNA and the common genetic code of all organisms stands as one of the most dramatic and compelling confirmations of a theory's predictions in the history of science.
Fair enough, but this experiment is frequently sited as proof positive that life was formed naturally.
I've never heard it cited as such. There is no such thing as "proof positive" in science. Theories can only be disproved, not proved. However, Miller's experiment confirmed an important prediction of the theory: if life formed spontaneously, then the fundamental building blocks of life must also be capable of being formed spontaneously.
The amino acids would have to form proteins and proteins require DNA/RNA in order to perform usefull functions.
Actually, this is not true. Many proteins perform useful functions all by themselves. Proteins can even form other proteins without the intervention of DNA or RNA. What DNA and RNA provide is a mechanism for "assembly-line" production of large numbers of different proteins. Moreover, RNA by itself can perform many of the functions of proteins. So it is possible to envision plausible schemes in which life started with proteins, with the whole DNA/RNA business added on later, or in which life started with something like RNA, with proteins being a later invention. Or both could have happened, with the present form of life being a fortunate hybrid.
DNA has a pretty delicate structure, it is unlikely to last very long by itself.
Also not true. DNA is quite stable and has even been recovered from fossils.
I know that people have some speculations but we haven't come close to producing life from natural compounds.
No, spontaneous generation of life is probably a sufficiently infrequent event that it is unlikely ever to be reproduced in a lab. And the first form of life was probably so different from modern cells that we might not recognize it even if we did manage to create it.
The philosophical problem is that neither position makes sense, existing forever, or being auto-created out of nothing.
One more possibility exists: given the possibility of time loops, God (or the Universe) could be self-created. But a circular explanation is not much more satisfying than an arbitrary assumption of eternal existence. And we still end up seeking a meta-explanation: how is it that the laws of nature allow such a thing?
It's unlikely that anybody will every create a life form by a Miller-type experiment, unless the probablility of life forming spontaneously is far greater than even the most enthusiastic proponents imagine. Moreover, it might be very hard to recognize a primodial life form. You could have one of Stuart Kauffman's sets of reciprocally catalyzing polymers (Stuart A Kauffman, The Origins of Order: Self-Organization and Selection in Evolution) or one of Cairns-Smith's replicating clay layers (A. G. Cairns-Smith, Seven Clues to the Origin of Life) in your soup and not even know it. And those are just the ideas that people have thought about.
As for where God came from, that is a stupid question. God created all things. He exists outside all things that were created, and one of those things was time. Without time the concept of beginning and end is absurd. Can we explain this? No. Do we need to? Of course not.
Absolutely. It is as absurd to insist that God requires a creator as it is to insist that the Universe requires one. In either case, one must accept that something can exist without being created by something else.
From what I recall (and a quick Google search), there is a big problem with Miller's experiment: the "environment" that Miller created was nothing like the environment of pre-biotic earth, becaus Miller's "atmosphere" was oxygen free, but geological evidence indicates that free oxygen has always been present on earth.
Miller's was the first of a series of experiments demonstrating that the building blocks of life are readily formed under a wide variety of conditions.
Also Miller had to create a "trap" to collect the amino acids being formed to protect them from breaking down again. What would the comparable "natural" trap be?
The problem here, once again, is that there are so many ways that this could happen that it is hard to guess which was most important. Binding to clays, convection currents shuttling compounds between reactive and protective environments, various types of spontaneously formed membranes, etc. etc.
Finally, the mix of both D and L aminos in Miller's soup presents a major problem. Living cells only use L amino acids. D aminos and proteins are toxic.
Not necessarily. Early life could well have used both. But once you go to "assembly line" production of proteins, it makes sense for life to standardize on one or the other, just as we use mostly right-handed screws. Left-handed nuts can be (and are) used, but for most purposes they add unnecessary complexity, and they are "toxic" if you you pick up a left-handed nut when you are expecting a right handed one.
...broke down as fast as they were made (in a carefully customised device, not in the wild), and were completely racemised at formation? Or that no evidence of a reducing atmosphere exists?
These days, his contribution is regarded as being the first of a series of studies showing that the fundamental building blocks of life are readily formed under a wide variety of conditions.
Most scientists will tell you the Carl Sagan coined phrase "If just one in a Billion, then one in that billion...." isn't plausible.
Actually, in my experience, most scientists have enough knowledge of statistics to know that it is plausible. Indeed, if the universe is infinite (as current astrophysical evidence suggests), then it doesn't matter how small the probability is. If it is possible at all, then it will happen somewhere.
Re:Maybe the problem is Minsky himself?
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It's not a dead end. He is complaining that there seems to be no interest in studying the big picture.
But as one of the pioneers in the field, wasn't it up to Minsky to produce exciting work that would create that interest? I can readily imagine that somebody going into the field today might think, "If somebody as bright as Minsky couldn't make major progress, maybe it's just not ready to be cracked."
OK, so somebody can obtain administrative access to my ABS. So what? I suppose that they could reprogram it to let them in, or keep me out. But since I have physical access to the station, I can always force a manual reset. I suppose that it might be useful as a preliminary step to turn off WEP, and avoid the work of cracking WEP.
I don't know about the quality of their current stuff, but I bought Bose 901s (Series I) in the late 60's after auditioning a huge number of speakers (my overall impression was that the more drivers a speaker had, the more muddled it sounded to me; the 901s were the only ones that sounded clear). Those speakers have continued to sound great for 30 years. Last year, I noticed some distortion that I traced to the equalizer. I sent it back to Bose and they fixed it for $35. I've run across manufacturers that wouldn't even look at a 10 year old product, let alone 30.
I'd rather deal with filtering out spam than have a tax on internet usage. Sure, a penny sounds reasonable. But the true cost is in establishing the principle that the government is entitled to collect revenue from routine internet usage. How long before the internet tax becomes a key element in funding every politician's favorite pork-barrel project? After all, two pennies is pretty reasonable, too. And three pennies isn't really so bad, and....
Re:All this testing, what about the tests themselv
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I'll rephrase my question: Given that any test will alter its subject (maybe insignificantly), what are the affects of the tests used here (MRI)?
Based simply upon the physics, one has to stretch pretty hard to even imagine a way in which there could be lasting effects of any significance. Once the spins relax, which happens very fast, everything should be back to normal.
Re:Got a whole lotta hype
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Now you are confusing
1)the finding of fact at law ie. you killed someone unlawfully which looks at who pulled the trigger, with
2)the sentencing procedure which takes into account why they pulled the trigger.
Nitpicking about what happens when is irrelevant to the point. Regardless of which stage of the process is involved, the bottom line is that the sentence (if any) imposed upon you for an identical act depends upon what was in your mind when you committed the act.
Re:Got a whole lotta hype
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You're confusing intent with motive, which legally are two entirely different things. The classic example (from first-year law school) is stealing. If someone robs a bank in order to feed their starving family, they are just as guilty as someone who robs it out of greed. Both had the same intent of absconding with someone else's property.
I can think of an obvious case in which motive matters. If my motive for shooting somebody is to protect myself or my family from what I believe (even mistakenly or foolishly, like the guy who shot the trick-or-treater) to be an imminent threat, I will not be subject to the same penalty as if I shoot him because I don't like the color of his tie. My intent is to shoot the person in both cases, only the motive is different. So some motives are recognized as a defense, others are not. Once again, state of mind is critical.
Re:Got a whole lotta hype
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Sure, because killing somebody is worse than just getting in a fight, i.e. you're sentenced partially on the severity of what you meant to do.
No, in both cases we are talking identical severity. Let's say that you take a hammer and smash somebody on the head repeatedly until their brains run out on the pavement. If you do this calmly, with the premeditated intention of killing him, you are subject to a more severe sentence than if you do it in an angry rage.
Hate crime legislation places more value on some people than others and is an obvious violation of equal protection under the law.
No, as in the case above, and in many other crimes, the penalty is based upon the motivation of the criminal, not the nature of the victim.
Re:All this testing, what about the tests themselv
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Brain Privacy
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Another example: X-ray use has been quite beneficial in medicine (CT scans, etc), but the tests require the use of high energy waves to measure attenuation. These waves have been shown to affect tissue tested (DNA damage).
X-rays are ionizing radiation--there is enough energy to break chemical bonds. That's not the case with MRI.
Re:jumping to conclusions
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Racism is a not really the right word. "Prejudice" might be a bit better. Or "inductive reasoning." The reality is that you are at greater risk from a person of a different race, because the other person might be a racist even if you are not. Your conscious mind might not want to face this, but your amygdala knows it. I imagine black people would show the same reaction to unfamiliar white faces. And probably young male faces would produce a stronger reaction than older or female faces.
Re:Got a whole lotta hype
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Brain Privacy
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If you assault someone without hating them for their race, you get the standard punishment. But if you do the exact same assault and feel hatred, you get an additional punishment.
So? Punishment has always depended upon one's thoughts. If I start a fight with somebody and kill them, it makes a big difference in my punishment whether I was planning to kill them them prior to the fight, or just did it on the spur of them moment.
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It's unlikely that anybody will every create a life form by a Miller-type experiment, unless the probablility of life forming spontaneously is far greater than even the most enthusiastic proponents imagine. Moreover, it might be very hard to recognize a primodial life form. You could have one of Stuart Kauffman's sets of reciprocally catalyzing polymers (Stuart A Kauffman, The Origins of Order: Self-Organization and Selection in Evolution) or one of Cairns-Smith's replicating clay layers (A. G. Cairns-Smith, Seven Clues to the Origin of Life) in your soup and not even know it. And those are just the ideas that people have thought about.
OK, so somebody can obtain administrative access to my ABS. So what? I suppose that they could reprogram it to let them in, or keep me out. But since I have physical access to the station, I can always force a manual reset. I suppose that it might be useful as a preliminary step to turn off WEP, and avoid the work of cracking WEP.
I don't know about the quality of their current stuff, but I bought Bose 901s (Series I) in the late 60's after auditioning a huge number of speakers (my overall impression was that the more drivers a speaker had, the more muddled it sounded to me; the 901s were the only ones that sounded clear). Those speakers have continued to sound great for 30 years. Last year, I noticed some distortion that I traced to the equalizer. I sent it back to Bose and they fixed it for $35. I've run across manufacturers that wouldn't even look at a 10 year old product, let alone 30.
I'd rather deal with filtering out spam than have a tax on internet usage. Sure, a penny sounds reasonable. But the true cost is in establishing the principle that the government is entitled to collect revenue from routine internet usage. How long before the internet tax becomes a key element in funding every politician's favorite pork-barrel project? After all, two pennies is pretty reasonable, too. And three pennies isn't really so bad, and....
Racism is a not really the right word. "Prejudice" might be a bit better. Or "inductive reasoning." The reality is that you are at greater risk from a person of a different race, because the other person might be a racist even if you are not. Your conscious mind might not want to face this, but your amygdala knows it. I imagine black people would show the same reaction to unfamiliar white faces. And probably young male faces would produce a stronger reaction than older or female faces.
I use privoxy with Mozilla. Pretty much all ads, even those on the page I'm reading, show up as peaceful grey checkerboards.