Science vs. Religion?

November 25, 2009

Science does not seem to have a firm position on miracles. There are lots of different ways scientists can legitimately look at miracles and explanations that depend on miracles.

Each of these progressions starts from statements that seem clearly true, and shades gradually into gray areas. At what point, in these slippery slopes, would you draw the line?
1) It is the job of a scientist to…

… try to understand how things would work if there were no miracles involved.

… assume that what they are studying does not involve miracles.

… assume that the natural world works entirely without miracles.

… disbelieve in miracles.

2) It is the job of a scientist to…

… increase the world’s stock of scientific knowledge.

… educate people about science.

… promote awareness of scientific explanations of things.

… promote belief in non-miraculous explanations for things.

… promote unbelief in miracles.

3) The theory of evolution is fundamental to biology, and…

… a non-miraculous explanation for life’s diversity.

… an adequate theory to replace the previous, miraculous explanation.

… a theory that should replace the previous, miraculous explanation.

… a theory that proves God did not create the species.

4) Therefore, scientists should…

… try to educate people about evolution.

… try to convince people that evolution is the best theory we have.

… directly attack creationist (miraculous) explanations



November 14, 2009

In Darwin’s time, the belief in the independent creation of species was mainstream, as was the belief that humans could not have been descended from animals.

In addition to his well-reasoned arguments (such as the occasional occurrence of zebra-stripes on young horses – he said that he’d almost as soon believe that God put seashells in the mountains to fool us, as believe that God put zebra stripes on non-zebras), he occasionally had a bit of fun.

Thus, in the second chapter of The Descent of Man, he writes:

“He who rejects with scorn the belief that the shape of his own canines, and their occasional great development in other men, are due to our early forefathers having been provided with these formidable weapons, will probably reveal, by sneering, the line of his descent. For though he no longer intends, nor has the power, to use these teeth as weapons, he will unconsciously retract his “snarling muscles” (thus named by Sir C. Bell), so as to expose them ready for action, like a dog prepared to fight.”

Digital Copies Needed

November 10, 2009

Reading Darwin gets my own brain working, and I’ve been thinking about the necessity of accurate copying in lifelike self-replicators.

While googling Stuart Kauffman, I came across a concept of “Lipid World” which proposes that life arose by the development of lipid vesicles. Lipids can self-assemble into cell-like enclosures with lipid bilayer walls. This is highly suggestive. But the Lipid World FAQ points out that lipid vesicles “give rise to somewhat imperfect copies of themselves” and concludes that “Life then moved on an axis of increasing FIDELITY rather than increasing complexity.”

It seems to me that in any given environment, it will either be the case that a large proportion of possible structures are “fit” – that is, self-sustaining through stability and/or replication – or only a few possible structures are “fit.”

If a large proportion of possible structures are fit, then those structures will arise easily, and each spontaneously appearing structure will evolve (without even needing replication) to a very fit state; then they will persist in that state, acting as an energy sink that precludes further advances and probably precludes the development of self-replication. Note that this is not intended as a description of life as we know it; rather, it is a description of non-living “natural processes.”

If only a small proportion of possible structures are fit, then any given accumulation of random variation from a fit structure is likely to be unfit. Thus, in a population reproducing by imperfect copying, the population’s fitness will tend to devolve.

Therefore, self-replicators, from the start, must have been based around a high-fidelity copying process – indeed, a digital copying process. Covalent chemistry is digital. If I understand correctly, lipid vesicle copying is not digital, even though it can transmit information.

To put this theory into concrete terms, it seems to me that the Lipid World would quickly converge to a sea of optimal vesicles, and then improvement would stop. These vesicles would be as “natural” and as non-living as clay particles. Either vesicles or clay particles might then have provided a substrate for the development of self-templating covalent polymers.

Since covalent chemistry is digital, self-replicating polymers would be able to explore thin and perilous pathways in the space of all possible molecules. As long as a sufficient number of “offspring” were identical to the parents, an arbitrarily large fraction of the variants could be less fit; competition would remove the less fit ones, and preserve the good-enough ones until the rare improvement came along.

For another writeup of this theory from a slightly different point of view, see my post on the origins of life on my “Responsible Nanotechnology” blog.


Darwin Predicted Evolutionary Psychology

November 10, 2009

According to Wikipedia, the term “evolutionary psychology” was probably coined in 1973.

Darwin predicted it in his Origin of Species. On the next-to-last page, he writes:

“In the distant future, I see open fields for far more important researches. Psychology will be based on a new foundation, that of the necessary acquirement of each mental power and capacity by gradation. Light will be thrown on the origin of man and his history.”

I’d been thinking about starting this blog for a long time, but it was reading that that tipped the balance. Darwin didn’t just invent clever ideas; he saw implications deeply. (At some point, I’ll be writing about how he described an early version of the mathematical idea of configuration space or state space.)

Of course, I’m not the first to notice that Darwin predicted evolutionary psychology. But I hadn’t realized it until I read it in the Origin.

Welcome to Reading Darwin!

November 10, 2009

I started this blog because I had so many insights while reading The Origin of Species, and I hope others will find some of them interesting.

I welcome all on-topic comments. However, miracles, including the miraculous or divine creation of species, are off-topic.

I hope to learn. I hope to get some of my remaining questions answered… and if I’m wrong about something, please tell me.

I’d welcome guest articles.