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Journal of No. 118


September 30th, 2005

Sorites, Semantics & Science @ 02:08 pm

Current Mood: profound
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Most antievolutionists seem to be okay with the idea of microevolution, but have a problem with the idea of macroevolution. They can imagine evolutionary changes within a species, but not a change into a different species. It struck me today... that this is related to the Sorites Paradox:

If you have a heap of sand and remove a single grain of sand, you still have a heap of sand, right?

For any heap of sand worthy of its name, this is true. You can always remove a grain of sand from a heap and still have a heap. But this leads to paradox, for if you continued the process, eventually there would come a point where you no longer had a heap. (unless of course, you started with an infinite heap of sand of a cardinality greater than your ability to handle.)

One can resolve this paradox by noting that the word 'heap' is a little vague, and that we treat this heap as though it were unchanged, when in fact it was changed by a little tiny bit. If we redefined 'heap' to be "a pile of sand that weighs more than a gram", it would obviously no longer be true that you could always remove a grain of sand from a heap and still have a heap. It's not really necessary to redefine words in this way, but at least it reassures us that the paradox really isn't a paradox, and the world isn't about to disappear in a poof of logical contradiction.

In the case of evolution, consider this statement: the offspring of a species are always of that species. Or to put it another way: cats always give birth to kittens. Nothing could be more obvious and true. Yet, taken to the logical extreme, it is a statement that macroevolution is impossible. It's cats, cats, cats, all the way down.

But just as the heap of sand will ultimately no longer be a heap if we keep picking away at it, the lineage of cats turns into something non-cat if we follow it back far enough.

Just as removing a grain of sand does not leave a heap absolutely unchanged, a kitten is not an exact clone of its parents. Its genetic make-up will be slightly different. Looking at cats as a whole, the frequency of genes in one generation will be slightly different from the frequency of genes in the next (unless cats are absolutely perfect, which I confess is a reasonable hypothesis.)

Before, it was the fuzzy word 'heap' that we could wiggle around to dispel the paradox. Here, the fuzzy (so to speak) concept is 'cat'. Or species, really. Just as there's no elegant way to determine when you have a heap that is about to turn into not-a-heap by the subtraction of a single grain, there's no elegant way to describe the boundary between the very first generation of cats and their not-cat ancestors.
We can make an arbitrary human decision that a heap must weigh at least one gram, and palaeontologists do much the same thing when they decide whether a particular fossil is part of species A or species B. Is that skull Homo sapiens or Homo heidelbergensis? But these arbitrary divisions obscure the continuous nature of the transformations: one grain at a time, or one shift in gene-frequency at a time.
 
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From:essentialsaltes
Date:September 30th, 2005 10:30 pm (UTC)

In related news...

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The California Superintendent of Schools offered some clear and elegant words about the nature of science and science education... and why ID is not a part of either.
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From:colleency
Date:September 30th, 2005 11:17 pm (UTC)
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This came at just the right time. I've been following an off topic thread at a cooking website that is discussing just this subject. I'm kind of defenseless on the subject, due to my poor science training/knowledge. There is much discussion by the pro-IDer about macro vs. micro evolution.

May I copy what you wrote over there?
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From:colleency
Date:September 30th, 2005 11:19 pm (UTC)
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I can't really use your link to the CA school districts memo, because the person in question keeps stating that ID is not religious, which leaves me scratching my head. How can you think that it isn't religious?
From:(Anonymous)
Date:October 1st, 2005 02:52 pm (UTC)
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The argument that IDers use against the accusation that they are just trying to let God in by the backdoor is that ID merely argues for the evidence of a purpose in how evolution has proceeded. The designer of that purpose could be anything from God to a very intelligent alien to the human engineers of a previously formed universe, etc. Its left open whether or not the purpose evidenced in evolution is a product of direct involvement (such as the being or beings in question actually eliminating species to allow select species to develop) or indirect influence (natural laws of the universe producing a filtering action to support certain kinds of species).

Either way, of course, the idea that one could develop an Intelligent Design theory of evolution without God has got to be begging the question. Because even if we replace God with "Zardoz, the collective of super smart immortal humans from a previous universe" we are left with the question of how THIER intelligence and evident design-abilities came about. The only way to stop the infinite regress is to introduce a being whose intelligence and designing power is inherent in their nature, i.e. God.

--- Steven Marc Harris
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From:essentialsaltes
Date:October 1st, 2005 12:38 am (UTC)
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May I copy what you wrote over there?

Be my guest!
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From:ladyeuthanasia
Date:October 1st, 2005 10:52 pm (UTC)
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Never protect me from your brain. I love the analogy. It's perfect.
From:aaronjv
Date:October 2nd, 2005 08:45 am (UTC)
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The way I interpreted Hawking's A Brief History of Time was that the Grand Unified Theory is so perfect (or some other theory is so perfect; a perfect equation) that it IS the creation itself. In other words, God is an equation that creates itself (and in creating itself, creates all the rest of the "laws" of the Universe).

The thing that bugs me about ID is the idea that this entity has a purpose for designing everything, or, that the designer continues to design things. What about new organisms/variant microbe strains going around killing people now? Were those designed as well? And, if so, doesn't that make God a fucking asshole? (Check out this article in the latest LA Weekly to see where I stole my idea).

Plus, I don't cotton to the idea of a Supreme Being who is at all interested in my day-to-day doings. I'd rather be left alone to figure it out, just like Suicidal Tendencies sings. God should just get me a Pepsi. All I want is a Pepsi. Just a Pepsi.
From:(Anonymous)
Date:October 2nd, 2005 10:04 pm (UTC)
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What about new organisms/variant microbe strains going around killing people now? Were those designed as well? And, if so, doesn't that make God a fucking asshole?

It ends up being the old "Problem of Evil" chestnut. Obviously, the answer to this is going to depend on how close the Designer is involved in fine tuning things. One possible answer is this: The Designer sets in motion a process which will produce a universe tuned in such a way as to allow for the eventual emergence of life forms similar to ourselves. If for example, the electron's charge were slightly different, or if the strong nuclear force were only 2% stronger, diprotons would be stable and hydrogen would fuse too easily, making stars as we know them impossible and prevent the universe from developing life as we know it. (This has an air of ad hock reasoning, admittedly.) Once life develops, natural selection enters the picture which essentially is nothing more than the way life forms and the environment interact.

To have natural selection, we need random mutations and an environment that eliminates. Both are the products of the way the universe is set up to begin with. There is no necessity involved in when the mutations necessary for an intelligent species to evolve. A quick look at our own Earth's history shows how difficult and unlikely it is. But there is a necessity that if and when such a being were to emerge, it would fill an ecological niche unpreviously occupied.

This is how I think the more scientific IDers are viewing the evolutionary record. There are obviously other variations, but its one that I think has the best chance of gripping with your objection. I say this because once they've established that the Designer has been letting a process work itself out, there is no need to explain his sudden absence when the Asian Avian Flu breaks out and kills thousands of people. This is where the ole Free Will defense of St. Augustine can come back into the picture. Why are there new organisms/variant microbe strains arriving on the scene today? Because choices made by human beings have acted as a selection pressure on those microbes. If human beings had suddenly disappeared a century ago, its highly unlikely that selection pressure on the old microbes would have ever made those advantageous mutations spread so quickly through the microbe population. Human beings are responsible for that evil. Especially those medical scientists who have been finding ways to kill those microbes and accelerate their evolution. (Though after listening to Tom Cruise, I'm guessing psychiatrists have their hand in there somewhere as well.)

Its interesting to note that natural evil, as opposed to the moral evil we are forcing microbe evolution to fit under above, was also blamed on human beings by Augustine in terms of our Fall in Eden. By sinning against God and eating from the Tree of the Knowledge of Good and Evil, we in effect stained nature to become imperfect. Its a result of his Platonism that Augustine sets up the solution to natural evil the way he does, but I can't help but think that if we see the physical world as being set up as a container of sorts for the eventual intelligent species, then natural evil, like earthquakes, hurricanes, asteroid impacts, etc, have a place as environmental pressures that aid in evolution. For example, for species to have a greater chance of variation it helps to isolate reproductive groups. Plate Tectonics allows for geographical isolation. Plate techtonics also allows for volcanos and earthquakes. Thus the best means for geographic isolation and climate variation brings with it the unfortunate result of natural evils. Therefore, YOU as a member of the intelligent species that this universe was designed for take part of the blame for the natural evil in this world. This being a way of understanding Original Sin. (And thus resulting in the eternal enmity of the Hounds of Tindalos for our species.)
From:aaronjv
Date:October 3rd, 2005 05:30 am (UTC)
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Therefore, YOU as a member of the intelligent species that this universe was designed for take part of the blame for the natural evil in this world.

So...it's my fault Hurrican Katrina killed people? How about this: It's George Bush's fault because he's incompetent and a Christian. That makes sense. It's Christianity's fault that people die.

Oh, and who are you and what are you saying?

Journal of No. 118