Friday, November 20, 2009
Tuesday, November 17, 2009
Wednesday, November 04, 2009
Why Evolution is True by Jerry Coyne
===================================================
Lecture by evolutionary geneticist Jerry Coyne about the evidence for evolution and why it is a fact.
Video posted by richarddawkinsdotnet on YouTube.
Saturday, October 10, 2009
Why design arguments fail
"Well, just look around you" is a response I often get when I ask what evidence there is for a Creator. The tacit assumption behind this response is that only by recourse to a divine designer can we account for the staggering complexity and variety of life on Earth. It's important to note from the outset that such a response is not actually an argument, however much the person uttering it may think it is, but is simply an expression of a subjective cognitive bias (reinforced, in many cases, by cultural influences, namely religious ones).
So, let's take the advice of the generic Creationist and do as they subscribe. Let's look around and see what we actually find.
One thing that sticks in the throat is the tremendous waste on display. In nature, there is a massive overproduction of offspring. Only a minority of the offspring produced within a population will grow up to themselves produce offspring. In elephant seals, for example, there is a massive excess of bachelor males who never get to mate at all. Animals themselves are also wasteful, in the sense that they have features about them that we would consider to be poorly "designed" if they were conceived of by an intelligence. Organisms are, if anything, too complex. When we design things, we try to minimise complexity. Having too much of it increases the odds of something going wrong since there are more opportunities for perturbations to make themselves felt during development, and it just doesn't make sense from an engineering point of view (which is the point of view that Creationists appeal to when they point to something as evidence for God). Finally, there is a third sense of waste, and this has to do with side-effects. Each year, literally millions of people are born with deformities that are at least partially attributable to genetic mutations resulting in too much or too little of some protein or growth factor or other product being manufactured in the cells. Millions of people aren't born at all, due to mutations that so catastrophically upset the developmental process that a viable individual is simply out of the question. It is easy to conceive of why these things happen: because alleles (the variants of particular genes) that are beneficial (or at least not harmful) in some circumstances are harmful in others. Since we reproduce through sex, we mix and shuffle alleles all the time. It is inevitable that there will be combinations of alleles that result in a phenotype for which the prospects of survival and reproduction are drastically reduced.
But might not these be part of some "greater plan"? They might, but if you allow yourself that lazy way out then you might as well stop doing science and be done with it. One can't discern "design" for something but then plead ignorance about something else that seems to go utterly against the proposition of design.
There are fundamental problems with the design argument that pre-empt the need to appeal to the now universally (within the scientific community) recognised alternative of evolution. Firstly, to say that an organism is design is to extend the analogy of human contrivance to a domain in which we simply don't know whether it is applicable. We know that we design things because we have plenty of evidence of it. We definitely find it easy and convenient to think of organisms as having being designed, but this doesn't mean that they were. For one thing, we've never seen this process take place, and have no direct or even indirect evidence of it. Furthermore, it should go without saying that there is a key difference between, say, a horseshoe and a horse: the former can't produce another version of itself while the latter can. From that alone we should see that we dealing with two vastly different artefacts: one for which it is unquestionably the case that an intelligence was required to bring it about, and the other for which we simply don't know. If we ask where horses came from and answer that they came from a Creator, we are then justified in asking where the Creator came from, and if we say that the Creator didn't require one himself, then we might as well say that horses have always existed. If we discern design on the basis of complexity, and from this discern the existence of a supreme being of some form or other, then on that very basis a designer is untenable, because all the more would we need to address the existence of the designer - the ultimate being, endowed with awesome powers beyond human comprehension - through design. The arbitrary cut-off point, "From here to here, design, but beyond here, no more", is simply a way to mask ignorance.
The analogy to human contrivance thus fails. And if we push it further, as David Hume did when he showed the flaws in the design argument, then we can come to some curious possibilities. In human engineering and construction, we usually deal with multiple people working on a project. If the design analogy is sound, why not suppose a team of deities rather than just one? Or why not suppose that, instead of the designer or designers possessing sublime intellects, they are actually fools who muddled the universe up on countless occasions before hitting upon the one we inhabit? How could we distinguish one possibility from the other? Both give the same result; neither is a priori more reasonable than the other if we take natural artefacts as the evidence to judge the likely answer. So even if we suppose design, there is no guarantee whatsoever that the designer will be God, or Allah, or any of the other deities that humanity has ever believed in.
Today, we have marshalled an impressive array of facts and observations that point to the fact of evolution. As a matter of fact, though, evolutionary ideas didn't begin with Darwin and Wallace; they have been floating around for millennia. Indeed, here we often find that analogies were being used in a different way: not to try to show how design can account for the world, but how things in the world can account for themselves through an historical process or unfolding. We might consider a tree developing and from that draw analogies about a long history of life on Earth, from which humanity eventually sprang. This just shows how analogies can be used to come to different conclusions, depending upon what the focus of interest is.
We now know about the actual history of life on Earth in some detail, and we can appeal to evidence rather than analogy to back up our claims. Evolution, the process by which life has diversified and complexified, is a fully satisfactory account of how we got here. To say that we need to invoke a Creator is to opt for a spectacularly superfluous and unparsimonious "solution", which, in reality, solves nothing, and in fact didn't solve anything even before evolution was shown to be the only coherent and viable explanation for what we see.
So, let's take the advice of the generic Creationist and do as they subscribe. Let's look around and see what we actually find.
One thing that sticks in the throat is the tremendous waste on display. In nature, there is a massive overproduction of offspring. Only a minority of the offspring produced within a population will grow up to themselves produce offspring. In elephant seals, for example, there is a massive excess of bachelor males who never get to mate at all. Animals themselves are also wasteful, in the sense that they have features about them that we would consider to be poorly "designed" if they were conceived of by an intelligence. Organisms are, if anything, too complex. When we design things, we try to minimise complexity. Having too much of it increases the odds of something going wrong since there are more opportunities for perturbations to make themselves felt during development, and it just doesn't make sense from an engineering point of view (which is the point of view that Creationists appeal to when they point to something as evidence for God). Finally, there is a third sense of waste, and this has to do with side-effects. Each year, literally millions of people are born with deformities that are at least partially attributable to genetic mutations resulting in too much or too little of some protein or growth factor or other product being manufactured in the cells. Millions of people aren't born at all, due to mutations that so catastrophically upset the developmental process that a viable individual is simply out of the question. It is easy to conceive of why these things happen: because alleles (the variants of particular genes) that are beneficial (or at least not harmful) in some circumstances are harmful in others. Since we reproduce through sex, we mix and shuffle alleles all the time. It is inevitable that there will be combinations of alleles that result in a phenotype for which the prospects of survival and reproduction are drastically reduced.
But might not these be part of some "greater plan"? They might, but if you allow yourself that lazy way out then you might as well stop doing science and be done with it. One can't discern "design" for something but then plead ignorance about something else that seems to go utterly against the proposition of design.
There are fundamental problems with the design argument that pre-empt the need to appeal to the now universally (within the scientific community) recognised alternative of evolution. Firstly, to say that an organism is design is to extend the analogy of human contrivance to a domain in which we simply don't know whether it is applicable. We know that we design things because we have plenty of evidence of it. We definitely find it easy and convenient to think of organisms as having being designed, but this doesn't mean that they were. For one thing, we've never seen this process take place, and have no direct or even indirect evidence of it. Furthermore, it should go without saying that there is a key difference between, say, a horseshoe and a horse: the former can't produce another version of itself while the latter can. From that alone we should see that we dealing with two vastly different artefacts: one for which it is unquestionably the case that an intelligence was required to bring it about, and the other for which we simply don't know. If we ask where horses came from and answer that they came from a Creator, we are then justified in asking where the Creator came from, and if we say that the Creator didn't require one himself, then we might as well say that horses have always existed. If we discern design on the basis of complexity, and from this discern the existence of a supreme being of some form or other, then on that very basis a designer is untenable, because all the more would we need to address the existence of the designer - the ultimate being, endowed with awesome powers beyond human comprehension - through design. The arbitrary cut-off point, "From here to here, design, but beyond here, no more", is simply a way to mask ignorance.
The analogy to human contrivance thus fails. And if we push it further, as David Hume did when he showed the flaws in the design argument, then we can come to some curious possibilities. In human engineering and construction, we usually deal with multiple people working on a project. If the design analogy is sound, why not suppose a team of deities rather than just one? Or why not suppose that, instead of the designer or designers possessing sublime intellects, they are actually fools who muddled the universe up on countless occasions before hitting upon the one we inhabit? How could we distinguish one possibility from the other? Both give the same result; neither is a priori more reasonable than the other if we take natural artefacts as the evidence to judge the likely answer. So even if we suppose design, there is no guarantee whatsoever that the designer will be God, or Allah, or any of the other deities that humanity has ever believed in.
Today, we have marshalled an impressive array of facts and observations that point to the fact of evolution. As a matter of fact, though, evolutionary ideas didn't begin with Darwin and Wallace; they have been floating around for millennia. Indeed, here we often find that analogies were being used in a different way: not to try to show how design can account for the world, but how things in the world can account for themselves through an historical process or unfolding. We might consider a tree developing and from that draw analogies about a long history of life on Earth, from which humanity eventually sprang. This just shows how analogies can be used to come to different conclusions, depending upon what the focus of interest is.
We now know about the actual history of life on Earth in some detail, and we can appeal to evidence rather than analogy to back up our claims. Evolution, the process by which life has diversified and complexified, is a fully satisfactory account of how we got here. To say that we need to invoke a Creator is to opt for a spectacularly superfluous and unparsimonious "solution", which, in reality, solves nothing, and in fact didn't solve anything even before evolution was shown to be the only coherent and viable explanation for what we see.
Thursday, September 10, 2009
Government in the future
==============================
Lecture from 1970 by Noam Chomsky on alienation and the prospects for true democracy. Posted by LaughingMan0X on YouTube.
Wednesday, September 09, 2009
The purpose of purpose
======================
Brilliant lecture by Richard Dawkins about the evolution of meaning and the sense in which purpose of a different kind long predates the purpose we normally think of in everyday parlance.
Video posted by richarddawkinsdotnet on YouTube.
Monday, August 31, 2009
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