Tag Archives: evolution

On the defense of ‘Evolutionary and Newtonian Forces’

Dr. Ellen Clark, a.k.a. Philosomama, has written a good review of Velasco & Hitchcock’s Evolutionary and Newtonian Forces [no paywall], one of the first papers to appear in the new open access journal Ergo. She points out that although V&H are trying to show how evolutionary forces are well described by analogy to classical causal Newtonian forces, they very nearly prove their opponent’s — the statisticalist — position. However, she comes to their defense.

Briefly, the causalist position is that evolutionary forces are causal like the force of Newtonian gravity. Natural Selection is a causal force that acts on biological organisms. The statisticalist position claims evolutionary phenomena are just the statistical result of the underlying causal physical processes. Hence, for the statisticalist, evolutionary phenomena have no force of their own.

V&H want to argue that evolutionary forces are like friction or elasticity. Dr. Clark points out that these forces can be problematic for their view, as they too note:

As Velasco & Hitchcock acknowledge, friction and elasticity are usually thought of by physicists as emerging “from the aggregate statistical behaviour of more elementary forces in certain kinds of system.” … But this is grist to the statistical view’s mill, we might say. They argue that natural selection supervenes on more basic causal events, without adding any extra causal power of its own. So these critics might happily accept that evolutionary forces are analagous to non-fundamental Newtonian forces, whilst holding their ground on the claim that natural selection is not causal.

However, causalist vs. statistical isn’t what I would like to discuss here; see her review for more discussion. Instead I’d like to focus on her appeal to the unknown as a defense of V&H’s causalist position. She claims that it is OK to consider evolutionary forces causal, like Newtonian forces, because Newtonian forces are mysterious. Since Newtonian forces are mysterious, we shouldn’t privilege their causality and should grant that right to not well understood biological forces as well. She says:

If there is anything magical about thinking of natural selection as an overall force producing all the multifarious births and deaths that we actually observe, then it is in very good company lumped in with physical forces.

This is an example of my favorite fallacy, Ignotum Per Ignotius: explaining something unknown by appealing to something even less understood. Let me explain why this is really problematic for her defense and ultimately for V&H.

Imagine a statisticalist pointing to their analogies and explanations of evolutionary phenomena and saying, “Evolution isn’t mysterious at all, and we have a perfectly good statistical explanation right here. The only causality is in the underlying fundamental physics.” The evolutionary causalist is then in the uncomfortable luddite position of insisting, without reason, that we don’t understand evolution. Appealing to an analogy with physics that supports the causal position is question begging, if there is no deeper reason why this analogy holds other than it supports the claim that evolutionary phenomena are mysterious and hence causal. Therefore without some other reason to support the causal view of evolutionary phenomena, appealing to mysteriousness does not justify the causalist position.

Moreover, without a supporting causalist argument, V&H have done the statisticalist’s work for them. As noted above, they have gone and shown exactly how evolutionary phenomena are like statistical results of underlying forces.

Posted in biology, evolution, philosophy, physics. Tagged with , , , , .

Working Hard on Special Biological Relativity

I’ve been working hard on Special Biological Relativity and it is taking up most of my blogging energy.  However, I do have some fun results:

Define Biological Energy as the ability to do work, the ability to change the environment.  Then Fitness can be related to Energy because the higher the fitness the greater the ability to change the environment.

E ∝ f

If we consider an organism that lives in a place with infinite resources – a Garden of Eden – and also replicates at the speed of the chemical reaction of replication – there is no maturation process, it immediately starts to replicated as soon as it is created – then it’s life is identical to it’s replication process.  Define d to be the speed of the chemical process of replication.  Then the ability of this organism to change the environment is given by it’s fitness, the rate it replicates at and it’s life:

E = fd2

Or something.

Posted in biology, evolution, fitness, philosophy, science, Special Relativity. Tagged with , , , , , .

Deriving Natural Selection = Fitness × Acceleration

As you can see from my previous post, I now have postulated a direct relation between Natural Selection and Fitness (N.S.=F.×A.).  This relation follows from the theory.

The short short short version of the theory is this general postulate: one organism’s traits are another’s environment and vice versa.  Hence all competition can be viewed as environmental phenomena.  This gives Natural Selection as a result of Fitness and an environmental factor, which I refer to as Acceleration.

If you want to see the paper as it stands now, you can access it here or below.[6in/120mm ebook formatted]

Posted in biology, evolution, fitness, General Relativity, philosophy, physics, Relativity, science. Tagged with , , , , , , .

Natural Selection = Fitness × Acceleration

Natural Selection is the force that changes species.

Fitness is the resistance to change in the rate of change of the species.

Acceleration is change in the rate of change of the species.

Natural Selection = Fitness × Acceleration

Posted in biology, evolution, fitness, philosophy, science. Tagged with , , , , .

Rewrite of Evolution

New theory of evolution!  Hooray!

Patched a bunch of things together to make a nice story.  Fixed the little issue about fitness being circular.  Expanded natural selection to apply more generally.  Causal structure.  Epistemological foundations.  ooOoOO0Ooooooo.

And it’s good fun.  I swear.  Epistemology, history of physics, evolution… makes me happy.  You should really read it.

Download here. [pdf, 304kb]

Posted in biology, epistemology, evolution, fitness, General Relativity, measurement, philosophy, physics, Relativity, science. Tagged with , , , , , , , .

Hypotheses Natura Non Fingo

Newton famously wrote [1] [2]:

I have not as yet been able to discover the reason for these properties of gravity from phenomena, and I do not feign hypotheses…  It is enough that gravity does really exist and acts according to the laws I have explained, and that it abundantly serves to account for all the motions of celestial bodies.

as a response to those who challenged him to provide causes of gravity.  He said, “Hypotheses non fingo,” or, “I feign no hypothesis,” or if you will, “I haven’t even a guess.”

Earlier in a letter he wrote:

That one body may act upon another at a distance through a vacuum without the mediation of anything else, by and through which their action and force may be conveyed from one another, is to me so great an absurdity that, I believe, no man who has in philosophic matters a competent faculty of thinking could ever fall into it.

These passages show that Newton recognized a fundamental causal problem within his theory: that although his mathematics described gravitational physics, it did not provide a causal explanation.  It was not until General Relativity 200 years later was this problem solved.

Recently another major fundamental theory of science has been accused of lacking the proper causal structure:  Fodor & Piatelli-Palmarini’s attack on evolution, What Darwin Got Wrong.  Consider what Fodor says in his recent reply to Block and Kitcher,

A mere chronicle of instances of adaptation would not therefore amount to a theory of adaptation. It would just be “natural history.” We haven’t the slightest doubt that Darwin thought that he had discovered a theory of adaptation. It was, to be sure, a pretty thin theory, as it would have to be in order to apply to evolving creatures as such, whatever their phenotypes and whatever their ecologies.

He is saying that evolution is a mere chronicle of natural history — not a cause of it — just as Newton’s gravitation described gravity without revealing its causal structure.  Later he says,

[Biologists should] give up on the project of finding a mechanism for evolution and study the fixation of adaptive traits case by case. Since all the evidence suggests that they are extremely heterogeneous, this should keep evolutionary biologists busy well into the indefinite future.

This means that biologists should give up on repairing evolution and just try to explain individual phenomena moving forward, just as physics moved forward even as Newton knew his theory was on metaphysical shaky ground.

Hence it is Fodor now saying, “Hypotheses non fingo,”  because he believes he can describe natural history accurately, but also has no guess as to what caused things to work out the way they did.

* * * * *

In light of this analysis, consider this statement from Block and Kitcher’s counter argument:

After our critique, Fodor and Piattelli-Palmarini have apparently decided that the crucial point is the lack of a “theory” of natural selection. But, as we have noted here, nobody needs a “theory” of the type they demand.

And this from Sober’s recent review [pdf]:

What is the net gravitational force now acting on the earth?  That depends on the mass of the sun, the moon, the stars, and of everything else.  It does not follow that there are no laws of gravity, only that the laws need to have numerous placeholders.  FP may object to my analogy because it is always the mass of these various objects and their distance from the earth that are relevant to the gravitational force that the earth experiences.  My reply is that this makes no difference…

Neither has understood the argument as presented above.  If Block and Kitcher had understood, then they would have recognized that yes, for the vast majority of people, the “‘theory’ of the type they demand” is unnecessary, but it is, nevertheless, of critical importance to the likes of Newton and Einstein.  If Sober had understood, then he wouldn’t have used the worst possible example to make his point:  by saying it is “always the mass of these various objects and their distance from the earth that are relevant,” and not mentioning motion, we know he was only thinking about Newtonian Mechanics.

* * * * *

Should we, with Fodor, believe that we are stuck in a philosophical absurdity?

No.  What I said in my original criticism of Fodor, found in What Fodor Got Wrong (18 March 09),  still applies.  Though the above description of the problem is likely clearer than my analysis based on his claims that Natural Selection is statistical and that the struggle for survival is only a metaphor, the problem of causal structure is the same.  My solution focuses on using individual struggles as local interactions of Natural Selection — like a gravitational field in General Relativity — and hence provides the causal structure that Fodor wanted.

[EDIT 6 April 2010:  I’m thinking I gave Fodor too much credit in this post.  I now think his arguments amount to saying that for each instance of evolution we have, we are merely relaying natural history, not a causal explanation.  The argument I attributed to Fodor above says that evolution by natural selection is natural history.  Fodor must be more agnostic about evolution’s ontology because of how he says it is possible to look for some alternative to natural selection in his reply to Block and Kitcher.  My solution is still viable though:  since I provide causal structure, this also provides how to describe evolution in a causal way.]

Posted in biology, evolution, General Relativity, philosophy, physics, Relativity, science. Tagged with , , , , , , , .

Fodor May Yet Be Clever

I was trying to figure out what Fodor could have been thinking.  Here’s what I came up with:

  1. If we are trying to figure out what Evolution has done, then we presuppose that Evolution is capable of doing something.
  2. If Evolution is capable of doing something, then there must be some mechanism of Evolution that does the doing.

Now imagine yourself in the position of the mechanism of Evolution that does the doing, i.e. the mechanism that selects the traits that yield a higher fitness.

The question becomes: is it possible for you to select for a trait?

The answer is NO.

To understand why, consider what happens when we try to give an evolutionary explanation of something:  we are beset by a near infinite selection of different possibilities.  Only through careful study can we narrow down which traits are actually the ones that increase an organism’s fitness and, if we are in a historical context, only give a most likely candidate for such a trait.

Now imagine yourself back in the position of the mechanism.  The mechanism is stuck with the exact same sort of problem that we have when trying to figure out what it has done:  it has no more an ability to select a single trait than we have to figure out which trait it has selected with our first guess.  Whenever it tries to select for a trait, it may mistakenly also select for another trait that is not so good for the organism, or it may not have even recognized the trait it thought it was selecting for.

Therefore, since this mechanism can’t work, evolution is bunk.

OK.  Now let’s take a step back and look at this argument.  Basically there are two parts:  the first part is an argument that there is a mechanism that does the doing and the second part says the mechanism can’t have done anything.  When I saw Fodor speak on this topic, I believe (it was a while ago now) he spent a good deal of time on arguing for the first part and I didn’t really understand what he was up to.  Now it makes sense because if we accept that there is some mechanism that does the doing, then we may be committed to admitting to at least some amount of skepticism about evolution based upon the second part.  Getting even some skepticism about evolution would be a sufficiently large accomplishment, and so I figure this must be Fodor’s ultimate goal.

In light of this argument I offer this wild conjecture for your reading pleasure:

Replace “mechanism” with “agent”.  Now, instead of an argument against evolution, it is an argument against Intelligent Design.  Intelligent Design has the designer/ agent built directly into it, and this makes the argument much more knock-down:  There is no need to argue for the existence of a mechanism because it is right in the title, and since the intelligence of ID is something like our intelligence, it makes sense that it would suffer from the same problems that ours does.

What I think happened is that Fodor was sitting around thinking why intelligent design doesn’t work and realized that if he could make a strong enough argument that evolution also required some sort of agent, in the form of an evolutionary mechanism, then he could return a similar result.  Since having a technical reason for discounting ID wouldn’t make much of splash, Fodor dropped the argument against ID and pursued the argument against evolution.

Personally I kind of like this argument against ID.  If I ever run into some ID people, I may even bring it up.

Posted in argumentation, biology, evolution, philosophy, random idiocy, science, wild conjecture. Tagged with , , , , , .

Fodor’s Intensional Criticism of Evolution

Fodor’s intensional criticism of evolution is that the process of evolution is unable to make the necessary distinctions in selecting traits.   This is to say that evolution itself cannot  select for specific traits.  If evolution can’t select for traits, then we will definitely not be able to figure out what’s happening based on evolution.  Hence evolution is not a good theory.

Does evolution need a mechanism to select for certain traits?

No, there is no need for a mechanism which decides that it wants a certain trait and then systematically selects for that trait.

Instead evolution is more like a Plinko / Pachinko machine with moving pins and prize locations.   Organisms – the balls – live and die by bouncing off whatever exists in their environment – pins and prizes -.  Whoever happens to land in a good location gets to have their genes replicated.  In this setup there is no need to appeal to some evolutionary mechanism to select traits because  with the environment and organism described, the evolutionary traits that will be selected are probabilistically determined.

Our evolutionary explanations, then, describe the environment – the position of the Plinko pins and prizes – and the biology of the organism – the shape and location of the Plinko ball – to show why that organism ended up in a position to replicate.  If we want to describe how we evolved to have hands, for example,  we show how organisms that more consistently landed in the right locations had the traits that led to us having hands, and not because there was a mechanism to pick out ‘having hand traits’ at the start.

Therefore Fodor’s argument from intensionality is a straw man:  Evolution does not need to be able to make the distinctions that Fodor says it needs to make.  Hence there is no problem within evolution.

[EDIT:  I’ve put up a new analysis (24 March 2010) of Fodor’s argument here: Hypotheses Natura Non Fingo]

For my take on what else Fodor got wrong, see my post What Fodor Got Wrong (which this argument actually presupposes), and the follow up Dismantling Fodor’s Argument.

Posted in biology, evolution, philosophy, science. Tagged with , , , .

On Block and Kitcher on Fodor

Ned Block and Philip Kitcher have posted a review of Fodor/Piatelli-Palmarini’s “What Darwin Got Wrong” (via Leiter).

It is a well executed, though flawed, counter to Fodor’s arguments.  First they give a nice rundown of the underdetermination issue I posted about here.

Then they discuss the “intensional fallacy”.  They argue that the crux of F & P’s argument can be seen as trying to split up the causal efficacious trait and the selected-for trait.  This means that F & P believe that there is no way to connect the evolutionary reason – the trait that increased an organism’s fitness – with our explanation of the trait that was selected-for.  Block & Kitcher argue that it is trivial to match the two up because

selection-for is a causal notion, and, since causation is extensional, so is selection-for.

Insofar as we believe that our explanation of the selected-for trait is extensional, i.e. truth-preserving when switching between different names of the same thing, we can say that we do pick out the causally efficacious trait.

Unfortunately Block and Kitcher sacrificed our normal concept of explanation to make this counter-argument.  They note that explanations are never normally extensional, but that we are making an exception in this case.  This is ok to do because

we thinking beings can give (intensional) explanations in terms of [one trait] rather than the other properties. In giving the explanation, we (thinking beings) describe the property in our preferred way.

I do not understand what is going on here.  Basically it looks as if “preferred way” is just a fancy way to say “own words”, but describing something in our own words doesn’t make it right.  Nor is it a reason to change what should count as an explanation.

Unless Block and Kitcher are prepared to give further justification as to why we should disregard our normal understanding of explanation, it looks as if their solution to Fodor’s argument is ad hoc.  They are using explanation* — which is a special kind of explanation that can be extensional — but they have not given a reason why explanation* should be preferred over of regular explanation (outside of causing Fodor trouble).  Without this reason, the use of explanation* is ad hoc, and hence the argument fails because it turns on an ad hoc premise: the assumption that explanation* can be substituted for explanation.

However, I did say above that Block and Kitcher’s argument is well executed:  My argument against using an ad hoc term-term* distinction is obscure compared to their argument and so, for the vast majority of people, it will appear that their argument is effective.  Overall this is a good thing: less nonsense needs to surround evolution (though I’ll be a little sad to see it go: I’m #1 in a Google search for “fodor what darwin got wrong“).

[EDIT:  I’ve put up a new analysis (24 March 2010) of Fodor’s argument here: Hypotheses Natura Non Fingo.  It also includes a review of the responses of Block, Kitcher and Sober ]

For my take on what Fodor got wrong, see my post What Fodor Got Wrong, and the follow up Dismantling Fodor’s Argument (also linked above in reference to underdetermination).  I’ll post something soon specifically addressing the intensionality issue:  Fodor’s Intensional Criticism of Evolution.

Posted in argumentation, biology, evolution, fitness, news, philosophy, science. Tagged with , , , , , .

Sexual Reproduction, The Case for, Round 2

Let us assume that there are different kinds of adaptations.  Specifically, some are better than others in the long run:  some adaptations will only make a difference in an organism’s ability to reproduce viable offspring over a short period of time, whereas others will be beneficial for many generations.

In asexual reproduction there is no mechanism for distinguishing between a short term beneficial adaptation and a long term beneficial adaptation.  This subjects long term beneficial adaptations to being potentially overshadowed by short term beneficial adaptations and genetic drift:  if a short-term genetic change  sweeps through a population, some adaptations can be wiped out.  This sort of (selected for or not selected for) genetic drift would be tempered if it were forced to go across the different biologies of the two sexes.

With sexual selection there is a mechanism for selecting long term beneficial adaptations over short term ones.  Long term beneficial adaptations will have to be good for both sexes:  if an adaptation is beneficial to both the male and female – individuals with significantly different biologies – then it is more likely to be  good for the entire species.  Short term beneficial adaptations may only be good for particular individuals or one sex, depending on the mutation.  This makes it less likely for short term, provincial adaptations (or drift) to last because they won’t be as effective across different the different biological make-up of the two sexes.

Therefore by distributing mutations across two different sexes – two similar but different biologies – long term beneficial adaptations can be selected for.

Posted in biology, evolution, fitness, philosophy, science. Tagged with , , , , , .