03.11.10

Against Physics as Ontologically Basic

Posted in argumentation, biology, epistemology, evolution, ontology, philosophy, physics, science at 12:42 am by nogre

1.  Biology is epistemically independent of physics:

Let’s assume that biology is not epistemically independent of physics, i.e. to know any biology we must first know something about physics.  However, consider evolution as determined by natural selection and the struggle for survival.  We can know about the struggle for survival and natural selection without appealing to physics — just as Darwin did when he created the theory — and hence we can fundamentally understand at least some, if not most, of biology independent of physics.

2.  Physics supervenes on biology:

Whatever ability we have to comprehend is an evolved skill.  Therefore any physical understanding of the world, as an instance of general comprehension,  supervenes on the biology of this skill.

3.  Biology is just as fundamental as physics:

If the principles involved in biology and physics are epistemically independent and each can be said to supervene on  the other, then neither has theoretical primordiality.

Therefore physics is not ontologically basic.

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[This argument was inspired by a discussion over at It's Only a Theory start by Mohan Matthen.

And I want it to be known that I HATE SUPERVENIENCE.  Basically if you use supervenience regularly then you are a BAD PERSON.  The only good argument that uses supervenience is one that reduces the overall usage of the word:  it is my hope that the above argument will prevent people from saying that biology supervenes on physics.  For every argument in which I thought that using supervenience might prove useful, I found a much, much superior argument that did not make use of the term.  I know you always live to regret statements like this, but right now I don't care.]

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02.24.10

Fodor May Yet Be Clever

Posted in argumentation, biology, evolution, philosophy, random idiocy, science, wild conjecture at 10:48 pm by nogre

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.

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Fodor’s Intensional Criticism of Evolution

Posted in biology, evolution, philosophy, science at 11:35 am by nogre

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.

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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.

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02.23.10

On Block and Kitcher on Fodor

Posted in argumentation, biology, evolution, fitness, news, philosophy, science at 12:13 pm by nogre

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“).

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.

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01.19.10

Aristotle’s Theory of TOPOS (Place)

Posted in Relativity, philosophy, physics, science at 12:22 am by nogre

[This is something I wrote before I had this blog, but I really like it and hope the readers here will find it interesting.]

The task of explaining Aristotle’s theory of place lies in the interpretation of this sentence: “Hence the place of a thing is the innermost motionless boundary of what contains it,” (Physics IV 212a20).  Now the idea of a motionless boundary for perceptible and obviously movable objects seems impossibly counterintuitive.  However, using Aristotle’s comments into the nature of place, we can understand how this theory extends beyond a simple boundary theory and into the modern era.

His discussion is started by making an observation:

The existence of place is held to be obvious from the fact of mutual replacement.  Where water now is, there in turn, when water has gone out as from a vessel, air is present; and at another time another body occupies this same place.  The place is thought to be different from all other bodies which come to be in it and replace one another.  What now contains air formerly contained water, so that clearly the place or space into which and out of which they passed was something different from both. (Physics IV 208b1-8)

Aristotle then makes some tentative moves into defining what could possibly fulfill the role of place.  First he discounts any idea that place could “be body; for if it were” he says, “there would be two bodies in the same place,” (209a6) and shows how this causes untold amounts of theoretical difficulty (ibid.).  Then he discusses how, as that which “primarily contains each body” (209b1), place could be viewed as the form or the matter.  Again he discounts either of these possibilities by noting that neither of them can be separated from a thing, whereas place may be.

The analysis turns at this point asking, “How many ways one thing is said to be in another,” (210a14) in the hopes of landing upon a useful interpretation of the notion of being-in.  Aristotle entertains the idea that a thing may be in itself, or more specifically, in itself “qua itself or qua something else” (210a27).  He gives the example of a jar of wine being in itself in virtue of the whole’s description in terms of its parts: the jar of wine is not reducible to a jar or some wine, but to their specific combination.  Hence that which is a subject may potentially be a container as well, as the jar is the container of the subject ‘jar of wine’.  However, he says this is impossible as no object is actually like this: the wine would have to be an equal part container, and the jar an equal part wine, else the whole of the ‘jar of wine’ will not be completely in itself.  It is in virtue of being different that the jar and the wine may come together, and hence he concludes that, “since the vessel is no part of what is in it (what contains something primarily is different from what is contained), place could not be either the matter or the form of the thing contained,” (210b27).

Aristotle then considers two sorts of boundary theories.  First, place is such that it is “some sort of extension between the extremities,” (211b7).  However, this sort of boundary exists independently of what is bounded and is permanent.  Insofar as anything moves, the place will change, and there will be two problems generated: 1. The boundary between, for example, the wine and air moving in a jar will be exactly coincident with the boundary between the air and wine, and each of these two boundary extensions will be partially coincident but must also be unique, and 2. There will be a place at the boundary of the displaced place, and so an infinite regress of places associated with previous places will be generated.

Finally Aristotle says, “place necessarily is… the boundary of the containing body at which it is in contact with the contained body,” (212a6).  Then, interestingly, he says, “Place… is rather what is motionless,” (212a17) and then, “Hence the place of a thing is the innermost motionless boundary of what contains it,” (212a20).  So how are we to make sense of containers that give us the boundaries but also do not move?

If we take our interpretation directly from the previous discussion of boundary, Aristotle seems to have made an awfully strange claim: place is a like a container that something perfectly fits in, and yet that container cannot itself move although what is contained therein necessarily can.  However, I would like to suggest taking him at his word in regards to place being necessarily a boundary.  It is necessarily a boundary of the containing body which is in contact with the contained body, but it is not sufficient that it be the boundary that most have in mind.  What has been missed by regarding the boundary as necessary and sufficient is the incorporation of Aristotle’s primary intuition into how we know place exists.

For us to notice any motion we need something stationary relative to the thing moving such that we may observe the motion as motion.  A stationary backdrop is necessary to view change.  Consider this example: it is a common experience to be sitting in traffic next to a bus.  When the bus starts to slowly pull forward sometimes it is possible to get the sensation that you have started to move backwards.  This sensation lasts until some other fact informs you that it was not you who were retreating, but the bus advancing.  In the first instance, the place that you inhabited was defined in terms of a stationary bus: any motion that occurred was relative to that fixed point.  When you realized it was the bus, and not you, that was moving, whatever it was that informed you that you were stationary became incorporated into the place.  Perhaps you saw a building and since it was not moving your senses of place and motion were reevaluated to accommodate this new information. Hence two different places were involved in this scenario: one corresponds to your (belief of) moving backwards and the other to the forward motion of the bus.  The first place has the innermost motionless boundary [illegitimately] defined in terms of the bus [since the bus was in motion], and the second has an expanded sense of place to include something motionless relative to both you and the bus. Place, therefore, not only encapsulates that which is moving, but also whatever is observing the motion and an independently stationary object.

When Aristotle says, “First then we must understand that place would not have been inquired into, if there had not been motion with respect to place,” (211a12) he was not making an idle comment on the ‘discovery’ of the phenomenon of place.  Instead, he was beginning his analysis with the most important feature to be explained.  Galilean relativity holds fundamentally that motion can only be defined relative to some “system of coordinates” (Einstein p. 14), i.e. something motionless with respect to the moving object.  Although Aristotle did not have the benefit of Descartes’ mathematical works he still recognized the need for a reference system unique to each motion.

Now that the meaning of the ‘motionless’ criterion has been explained, what does ‘innermost’ mean if the boundary may include objects at a significant distance from the one we are describing?  The Earth is, in some sense, the place of all sublunary objects, but it is surely not the innermost boundary.  Again appealing to the exact phenomenon that Aristotle was dealing with yields the correct explanation: the motion of an object with respect to its place cannot be described by saying that the place of the thing is Earth.  Instead the innermost boundary should be the first boundary for which the description of motion and place of the thing make sense.  In the example of swirling wine in a jar (with the jar held steady but the wine still moving), the place of the wine can be said to be the jar because it describes the closest motionless boundary.  One might say that the place of the wine is equally on the table, or in someone’s hand, but both of these descriptions are related to motion other than that of wine swirling in the jar, and are really just shorthand for ‘the jar of wine is on the table, or in hand’ (consider, “The wine is on the floor,”: no swirling to be had).  The correct place of the moving bus example was the street, which could reasonably include things such as houses and other stationary objects, the most important one being the road.  Aristotle gives the ancient version of this, just before his final definition of place, in terms of the motion of a boat, such that it must be defined in terms of the whole river, which is taken as stationary (212a19).

One may think that I am being too charitable to Aristotle at this point because it may look that I have implied that the ‘innermost’ criterion of the theory will do all the work of translation between coordinate systems, which it does not seem to do.  However, Aristotle allows for the fact that we may treat a vessel such as a boat as a “transportable place” (212a14).  Hence we may allow for the things within a boat to have motion independent of a preferred fixed reference system.  This connection drawn between vessel and place gives the final aspect needed for a true relativity theory.  Historically the example of a boat on a river (212a19) is striking because Galileo uses the same example of a ship in his Dialogue Concerning the Two Chief World Systems (Salgado).

Commentary

Historically Aristotle’s theory of place has been treated as a simple boundary theory coupled with a few very strange statements that were assumed to be preliminary investigations into different methods of solving blatant paradoxes (King 91).  My suspicion for why this happened is twofold.  First, philosophy of place sounds like the most dry and uninteresting subject possible and hence it was not given its due study time over the course of history (after Aristotle that is).  Secondly, the modern formulation of relativity is given according to Einstein’s theory of Special Relativity.  Insofar as this is a theory of relative motion, it is easy to overlook the fact that it applies to objects without motion, things in place.  Aristotle’s formulation is none the weaker because of the way he cast his theory, but it is much more obscure to the modern reader, as Aristotle’s relativity is developed in a somewhat inverse way with respect to modern relativity.

Bibliography

• Barnes, J. ed. The Complete Works of Aristotle v.2, Princeton U. Press, Princeton 1995
• Einstein, Albert Relativity: The Special and General Theory Lawson trans.  Pi press, NY, NY 2005
• King, H. R., “Aristotle’s Theory of TOPOS,” Classical Quarterly #44 1950, pp. 76-96
• Salgado, Rob “Galileo’s Parable of the Ship” http://physics.syr.edu/courses/modules/LIGHTCONE/galileo.html Accessed 2/24/06

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12.31.09

Genetic Drift and the Uncertainty Principle

Posted in Relativity, biology, evolution, measurement, philosophy, physics, science at 4:48 pm by nogre

I have previously argued that the history of species must be treated like a evolutionary trajectory: we can only appreciate a species in a relative sense, just as we must evaluate physical trajectories relative to our own motion.

But what happens when we try to measure the very small in physics?  We find there is a limit to the precision at which we can measure, as given by the uncertainty principle.

This suggests that there may be some similar limit when it comes  to measuring small changes in species.  The more we try to pin down exactly what a species is, the less sure we will be about its future and the more we measure the direction the species is heading, the less sure we will be about exactly what constitutes that species.

If genetic drift is just another way of saying that we cannot pin down the exact genetic make-up of a species then drift may be considered to be an instance of the uncertainty principle.

and HAPPY NEW YEAR

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10.18.09

Monty Redux

Posted in epistemology, game theory, logic, philosophy at 6:37 pm by nogre

In the Monty Hall Problem a contestant is given a choice between one of three doors, with a fabulous prize behind only one door. After the initial door is selected the host, Monty Hall, opens one of the other doors that does not reveal a prize. Then the contestant is given the option to switch his or her choice to the remaining door, or stick with the original selection. The question is whether it is better to stick or switch.

The answer is that it is better to switch because the probability of winning after switching is two out of three, whereas sticking with the original selection leaves the contestant with the original winning probability of one out of three. Why?

The trick to understanding why this occurs is to view the situation not from the contestant’s viewpoint, but from Monty Hall’s. At the outset, from Monty’s point of view, the contestant has a one out of three chance of guessing the correct door. In the likely situation (two out of three) that the contestant chose wrongly, Monty then has to know where the prize is among the two remaining doors in order to open a door that does not reveal the prize. So Monty opens a door not revealing the prize and asks the contestant whether he or she would like to switch or not.

However, the contestant knows that in the likely (two out of three) situation that the initial choice was wrong, Monty had to know where the prize was in order to open the door that did not contain the prize. Since the contestant knows that Monty has to know where the prize is to make the correct choice, the contestant can (in this likely case) place him or herself in Monty’s shoes. At this point Monty knows that the remaining door is the one that contains the prize, and hence the contestant should switch.

If we consider the unlikely situation in which the contestant initially chose the door with the prize behind it, then this line of reasoning will not work. Imagine that Monty forgets the location of the prize every time the contestant guesses correctly. In this situation he can still open either of the remaining doors without ever ruining the game. From his perspective the location of the prize is unrelated to his actions; it played no part in his decision to open one door or another (he merely chose a door the contestant hadn’t).

So, in the one out of three case where the contestant initially selected the correct door, there is no way to deduce whether switching is beneficial based upon placing oneself in Monty’s shoes:  the situation where Monty has forgotten the prize’s location is indistinguishable from a situation in which he has not forgotten. Without any way to further analyze the situation and tilt the odds to over one out of three, the contestant should always assume that he or she is in the previous, more likely, situation and take the opportunity to switch.¹

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¹Imagine that the contestant has a guardian angel that will let the game run its course if the contestant switches doors, but will change the location of the prize such that if the contestant sticks with the original door the angel will make sure that the contestant wins four out of five times. Then the probability of winning while switching will stay at 2/3 but the probability of winning while sticking will be 4/5. If the contestant had some way of divining that this was happening, this would be a case in which further analysis would be of benefit.

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10.15.09

Climate Change

Posted in internet, philosophy at 12:31 am by nogre

This is a post for Blog Action Day 09!

If the climate changes rapidly enough, the human race is finished.  If the climate does not change quite that rapidly, we’ve got other problems.

For the sake of argument, let us assume that we are not beings in some religious pantheon, but are merely biological organisms of this Earth.  If the climate changes, i.e. if nature as we know it no longer exists, then how are we to think of ourselves?

For our entire history we have lived within a climate that is amenable to us.  Living in a new climate would be like living on an alien planet, without hope of returning to Earth.  The problem is:  we are not aliens, we’re Earthlings.  If we are not Earthlings, what are we?  Hence the problem of climate change is more than a problem of our survival, it is an existential problem of our species.

We don’t need any more existential problems, and since this is one preventable, lets do something about it.

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10.08.09

Sexual Reproduction, The Case for, Round 2

Posted in biology, evolution, fitness, philosophy, science at 7:24 pm by nogre

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.

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10.01.09

Sexual Reproduction

Posted in biology, evolution, fitness, game theory, philosophy, science at 11:20 am by nogre

Say you are a single celled organism.  To reproduce you have to double your size and then you need to split yourself in half.  Repeat indefinitely.

Now say you are a single celled organism that has the option to reproduce sexually.  To reproduce you need to increase yourself to 3/2 your original size and find a similar mate.  Then you both contribute 1/2 to the new organism and repeat indefinitely.

Asexual reproduction requires you to double in size; sexual reproduction requires only a 3/2 increase.  Therefore the turn-around time for sexual reproduction is inherently shorter than for asexual reproduction (assuming there are viable mates readily available).

Is there a selective benefit to a shorter turn around time for reproduction?  If the species must constantly be adapting to a changing environment (that would be everyone), then having a higher rate at which new mutations (and thence adaptations) are introduced into the population is critical.

Secondly, given that there is enough food but it takes time to collect, I count more offspring for sexual reproduction:

In sexual reproduction, there is an additional child from the first generation of children (as compared to asexual splitting) created in the same amount of time: At the +50% mark #1 & #2 mate to create #5, and #3 & #4 mate to create #6.  Then, at the 100% mark (or plus an additional 50%) #1 & #2 mate to create #7, #3 & #4 mate to create #8, and, at the same time, the initial children #5 & #6 mate to create #9.  #9 is also one generation ahead of the offspring of asexual replication.

Now, to be honest, I’m confused.  I don’t think that anything above is particularly complicated.  However, Wikipedia does not note this as a benefit of sexual reproduction.  It actually says that asexual reproduction is much faster.  This makes me think that I must have made a mistake or else someone would have added it.

The going theory appears to be that since every organism in an asexually reproducing species can give off children, then there is twice the potential for offspring.  This completely ignores any struggle that an organism might have that would prevent it from reproducing, or that work can be split with a mate making it easier to reproduce.

My main assumptions are, among others, that there already is a significant population of organisms, the organisms are not too fussy about their mates (no significant waste of energy searching for a mate),  energy / work is being split with the mate, and that the limiting factor has to do with gathering food.  I can’t see how, if these (reasonable?) assumptions hold, sexual reproduction isn’t the dominant, winning strategy.

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