Tag Archives: Watson

Scientific American assesses naturalistic explanations for the origin of life

From Scientific American. (H/T Letitia via Mary)

Excerpt:

As recently as the middle of the 20th century, many scientists thought that the first organisms were made of self-replicating proteins. After Francis Crick and James Watson showed that DNA is the basis for genetic transmission in the 1950s, many researchers began to favor nucleic acids over proteins as the ur-molecules. But there was a major hitch in this scenario. DNA can make neither proteins nor copies of itself without the help of catalytic proteins called enzymes. This fact turned the origin of life into a classic chicken-or-egg puzzle: Which came first, proteins or DNA?

RNA, DNA’s helpmate, remains the most popular answer to this conundrum, just as it was when I wrote “In the Beginning…” Certain forms of RNA can act as their own enzymes, snipping themselves in two and splicing themselves back together again. If RNA could act as an enzyme, then it might be able to replicate itself without help from proteins. RNA could serve as gene and catalyst, egg and chicken.

But the “RNA-world” hypothesis remains problematic. RNA and its components are difficult to synthesize under the best of circumstances, in a laboratory, let alone under plausible prebiotic conditions. Once RNA is synthesized, it can make new copies of itself only with a great deal of chemical coaxing from the scientist. Overbye notes that “even if RNA did appear naturally, the odds that it would happen in the right sequence to drive Darwinian evolution seem small.”

The RNA world is so dissatisfying that some frustrated scientists are resorting to much more far out—literally—speculation. The most startling revelation in Overbye’s article is that scientists have resuscitated a proposal once floated by Crick. Dissatisfied with conventional theories of life’s beginning, Crick conjectured that aliens came to Earth in a spaceship and planted the seeds of life here billions of years ago. This notion is called directed panspermia. In less dramatic versions of panspermia, microbes arrived on our planet via asteroids, comets or meteorites, or drifted down like confetti.

John Horgan is not a Christian, nor even a theist. This is the state of the art if you are a naturalist.

Basically, you have at most a couple hundred million years from the time the Earth cools to the appearance of first life. You are unlikely to get one measly protein without an intelligence arranging the amino acids. This is assuming we spot you a favorable environment for creating amino acids without intervention. And then there would still be the problem of sequencing the proteins.

Atheists oppose science and evidence

Theists support science and evidence

Can computers become conscious by increasing processing power?

There is a very famous thought experiment from UC Berkeley philosopher John Searle that all Christian apologists should know about. And now everyone who reads the Wall Street Journal knows about it, because of this article. (H/T Sarah)

Searle is writing about the IBM computer that was programmed to play Jeopardy. His Chinese room example shows why no one should be concerned about computers acting like humans. There is no thinking computer. There never will be a thinking computer. And you cannot build up to a thinking computer my adding more hardware and software.

Excerpt:

Imagine that a person—me, for example—knows no Chinese and is locked in a room with boxes full of Chinese symbols and an instruction book written in English for manipulating the symbols. Unknown to me, the boxes are called “the database” and the instruction book is called “the program.” I am called “the computer.”

People outside the room pass in bunches of Chinese symbols that, unknown to me, are questions. I look up in the instruction book what I am supposed to do and I give back answers in Chinese symbols.

Suppose I get so good at shuffling the symbols and passing out the answers that my answers are indistinguishable from a native Chinese speaker’s. I give every indication of understanding the language despite the fact that I actually don’t understand a word of Chinese.

And if I do not, neither does any digital computer, because no computer, qua computer, has anything I do not have. It has stocks of symbols, rules for manipulating symbols, a system that allows it to rapidly transition from zeros to ones, and the ability to process inputs and outputs. That is it. There is nothing else.

By the way, Searle is a naturalist – not a theist, not a Christian. But he does oppose postmodernism. So he isn’t all bad. But let’s hear from a Christian scholar who can make more sense of this for us.

Here’s an article by Christian philosopher Jay Richards.

Excerpt:

Popular discussions of AI often suggest that if you keep increasing weak AI, at some point, you’ll get strong AI. That is, if you get enough computation, you’ll eventually get consciousness.

The reasoning goes something like this: There will be a moment at which a computer will be indistinguishable from a human intelligent agent in a blind test. At that point, we will have intelligent, conscious machines.

This does not follow. A computer may pass the Turing test, but that doesn’t mean that it will actually be a self-conscious, free agent.

The point seems obvious, but we can easily be beguiled by the way we speak of computers: We talk about computers learning, making mistakes, becoming more intelligent, and so forth. We need to remember that we are speaking metaphorically.

We can also be led astray by unexamined metaphysical assumptions. If we’re just computers made of meat, and we happened to become conscious at some point, what’s to stop computers from doing the same? That makes sense if you accept the premise—as many AI researchers do. If you don’t accept the premise, though, you don’t have to accept the conclusion.

In fact, there’s no good reason to assume that consciousness and agency emerge by accident at some threshold of speed and computational power in computers. We know by introspection that we are conscious, free beings—though we really don’t know how this works. So we naturally attribute consciousness to other humans. We also know generally what’s going on inside a computer, since we build them, and it has nothing to do with consciousness. It’s quite likely that consciousness is qualitatively different from the type of computation that we have developed in computers (as the “Chinese Room” argument, by philosopher John Searle, seems to show). Remember that, and you’ll suffer less anxiety as computers become more powerful.

Even if computer technology provides accelerating returns for the foreseeable future, it doesn’t follow that we’ll be replacing ourselves anytime soon. AI enthusiasts often make highly simplistic assumptions about human nature and biology. Rather than marveling at the ways in which computation illuminates our understanding of the microscopic biological world, many treat biological systems as nothing but clunky, soon-to-be-obsolete conglomerations of hardware and software. Fanciful speculations about uploading ourselves onto the Internet and transcending our biology rest on these simplistic assumptions. This is a common philosophical blind spot in the AI community, but it’s not a danger of AI research itself, which primarily involves programming and computers.

AI researchers often mix topics from different disciplines—biology, physics, computer science, robotics—and this causes critics to do the same. For instance, many critics worry that AI research leads inevitably to tampering with human nature. But different types of research raise different concerns. There are serious ethical questions when we’re dealing with human cloning and research that destroys human embryos. But AI research in itself does not raise these concerns. It normally involves computers, machines, and programming. While all technology raises ethical issues, we should be less worried about AI research—which has many benign applications—than research that treats human life as a means rather than an end.

Jay Richards is my all-round favorite Christian scholar. He has the Ph.D in philosophy from Princeton.

When I am playing a game on the computer, I know exactly why what I am doing is fun – I am conscious of it. But the computer has no idea what I am doing. It is just matter in motion, acting on it’s programming and the inputs I supply to it. And that’s all computers will ever do. Trust me, this is my field. I have the BS and MS in computer science, and I have studied this area. AI has applications for machine learning and search problems, but consciousness is not on the radar. You can’t get there from here.

Doug Axe explains the chances of getting a functional protein by chance

I’ve talked about Doug Axe before when I described how to calculate the odds of getting functional proteins by chance.

Let’s calculate the odds of building a protein composed of a functional chain of 100 amino acids, by chance. (Think of a meaningful English sentence built with 100 scrabble letters, held together with glue)

Sub-problems:

  • BONDING: You need 99 peptide bonds between the 100 amino acids. The odds of getting a peptide bond is 50%. The probability of building a chain of one hundred amino acids in which all linkages involve peptide bonds is roughly (1/2)^99 or 1 chance in 10^30.
  • CHIRALITY: You need 100 left-handed amino acids. The odds of getting a left-handed amino acid is 50%. The probability of attaining at random only L–amino acids in a hypothetical peptide chain one hundred amino acids long is (1/2)^100 or again roughly 1 chance in 10^30.
  • SEQUENCE: You need to choose the correct amino acid for each of the 100 links. The odds of getting the right one are 1 in 20. Even if you allow for some variation, the odds of getting a functional sequence is (1/20)^100 or 1 in 10^65.

The final probability of getting a functional protein composed of 100 amino acids is 1 in 10^125. Even if you fill the universe with pre-biotic soup, and react amino acids at Planck time (very fast!) for 14 billion years, you are probably not going to get even 1 such protein. And you need at least 100 of them for minimal life functions, plus DNA and RNA.

Research performed by Doug Axe at Cambridge University, and published in the peer-reviewed Journal of Molecular Biology, has shown that the number of functional amino acid sequences is tiny:

Doug Axe’s research likewise studies genes that it turns out show great evidence of design. Axe studied the sensitivities of protein function to mutations. In these “mutational sensitivity” tests, Dr. Axe mutated certain amino acids in various proteins, or studied the differences between similar proteins, to see how mutations or changes affected their ability to function properly. He found that protein function was highly sensitive to mutation, and that proteins are not very tolerant to changes in their amino acid sequences. In other words, when you mutate, tweak, or change these proteins slightly, they stopped working. In one of his papers, he thus concludes that “functional folds require highly extraordinary sequences,” and that functional protein folds “may be as low as 1 in 10^77.”

The problem of forming DNA by sequencing nucleotides faces similar difficulties. And remember, mutation and selection cannot explain the origin of the first sequence, because mutation and selection require replication, which does not exist until that first living cell is already in place.

But you can’t show that to your friends, you need to send them a video. And I have a video!

A video of Doug Axe explaining the calculation

Here’s a clip from Illustra Media’s new ID DVD “Darwin’s Dilemma”, which features Doug Axe and Stephen Meyer (both with Ph.Ds from Cambridge University).

I hope you all read Brian Auten’s review of Darwin’s Dilemma! It was awesome.

Related DVDs

Illustra also made two other great DVDs on intelligent design. The first two DVDs “Unlocking the Mystery of Life” and “The Privileged Planet” are must-buys, but you can watch them on youtube if you want, for free.

Here are the 2 playlists:

I also recommend Coldwater Media’s “Icons of Evolution”. All three of these are on sale from Amazon.com.

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