Atheism+: Of Opportunity and Outcome.

I know that some of you might be capital-L Libertarians, and that some of you might be the lowercase-L ones who find the American Right Wing Nutcase Libertarians absolutely insufferable. And yes, I know that some of you aren't libertarians at all. But there's an argument that keeps getting thrown around that I thought I'd debunk.

The following material is flagged Yellow Level. It contains material that is disputed by some experts but accepted by others. Caution is advised when deciding whether you personally choose to believe it.

Now then, some people say "I'm not against equality of opportunity, I'm against enforcing equality of outcome. It isn't fair to the hard workers for someone to be given the same outcomes they earned just for being black/female/gay/etc. Why do you keep insisting that I'm racist/sexist/homophobic for saying this?"

And here is where I will explain, in detail, that yes, that is a bigoted argument. I will tell you why accepting that argument makes you bigoted. If you dislike being called bigoted more than you dislike actually being bigoted, this is the moment when you should  leave now and come back next week.

Let us start with a few basic premises:
P1: Inequalities of outcome exist, when not compensated for.
P2: Those inequalities have a statistically significant tendency to favor some ethnic groups, genders, sexual orientations, and such over others.
P3: Any difference in individual outcomes results from an inherent trait (defined as a trait that is purely internal to a person), an extrinsic trait (defined as a trait that results from the actions of others, including actions based on intrinsic traits; this is what we will discuss when considering differences of opportunity, [EDIT: as well as initial conditions, such as family situation]), or a difference in luck (defined as traits or differences in circumstance that are neither intrinsic nor extrinsic as defined above, such as differences in the realization of an opportunity due to events beyond the control of either the individual or any person with power over the individual).
P4: Luck cannot account for statistically significant differences between groups. That is what statistical significance means.
P5: Any inherent trait that is evenly distributed (defined as distributed as probability dictates without any bias toward nor against any population) between all populations cannot cause a statistically significant difference of outcomes.

Let us add an implication of that argument as a premise:
P'6: It is possible, given the current population, for general equality of opportunity to coexist with general inequality of outcome.

Now, let us draw conclusions:
C1 (P3, P4, P5): If a statistically significant difference in outcomes exists between groups, it must result from either a difference in opportunities or an inherent trait present in one group to a statistically significant greater degree than in the other.
C2 (P2, C1): Either different groups have significantly different opportunities, or inherent traits are distributed such that an inherent trait impacting outcomes is predicted by membership in one group.
C'3 (P'6, C2): An inherent trait impacting outcomes is predicted by membership in one group.

Or, in other words, if you believe that significant inequality between average outcomes of racial, gender, or similar groups does not imply inequality between opportunities, you logically must believe that one group is less moral/intelligent/hardworking/suited for the task in question than another, which is the definition of bigotry.

That said, though, there's multiple kinds of bigotry. You might be making arguments that you haven't thought all the way through, or you might not have noticed the tendency of black characters to die a lot in movies, or you might be the person who uses the word "f*****" without realizing what it means. The fact that you are actually concerned about being seen as racist/sexist/ableist/etc. seems to show that you aren't the sort of person who goes around burning crosses.

The Bedlamite's Own Ethics II: Morality as Oppression

One important thing to keep in mind when examining or devising a code of ethics is that ethics can often serve as a means of enforcing existing power structures. History and law, it is famously said, are written by the winners, and they often serve the purpose of making sure the winners stay winners.

The following material is flagged Yellow Level. It contains material that is disputed by some experts but accepted by others. Caution is advised when deciding whether you personally choose to believe it.

Let us examine a famous case of this: that of Genesis 9:25. In the Bible, specifically the Book of Genesis, it is commanded that the sons of Canaan serve the sons of his brothers and cousins, because of the (unspecified) actions of his father Ham. It is difficult to believe that there were no Canaanites who thought, "hey, why are we doing this? We can see that the sons of Israel are free, and we are not; why shouldn't we be free?". And at some point, our theoretical slave mentions this within earshot of his master. And the master drags him before the temple leadership. And the priest hears both sides of the case. And then the priest carefully consults the Books. And then the priest mentions the "Cursed be Canaan" line. And who is a mere human to question the word of God (well, Noah actually, who was speaking for God at that point)?

In fact, it's not difficult to imagine that a slightly-less-than-ethical priest added the story when facing that exact situation shortly after the Israelites raided Canaan.

From a memetic perspective, the morality promoted by a society is simply a memeplex that dictates a set of "Thou Shalt"s and "Thou Shalt Not"s. Memes that lead to a more effective society ("thou shalt not kill", "thou shalt breed") survive, while memes that lead to a less effective society ("thou shalt steal", "thou shalt not go to war") are rejected. But these memes are rules handed down from an authority, and as such tend to have their own rules mixed in that serve no purpose but to cement the existing power structure.

Thou Shalt Not Hold Controversial Opinions.
Thou Shalt Not Rebel Against Thine Betters.
Thou Shalt Know Thy Place.
Thou Shalt Obey Thy Superiors.

This is not to say, of course, that all of a code handed down from an authority figure is wrong. But one must ask: is this rule in place because it helps society function better, or because it keeps those at the top on top? (And, for that matter, should the society in question continue to function, if it needs that rule to exist; but that is a question for another time.)

There are a few solutions to this problem.

One is Kant's Categorical Imperative. Kant proposed that one "should only act by that maxim that one would accept as a universal rule"; that is, act only in a given manner if one would allow others to act in the same manner. That is, there is one set of rules, and those rules apply equally to everyone. There are problems with this, though: society may have imbalances that favor one group over another, even if the rules are the same. Personal circumstances may render one set of rules oppressive to one person that are trivial to another.

Another solution is to constantly re-examine the rules and their impacts. Keep an open mind, looking at ways that the rules might impact others.

Atheism+: A Glossary of Terms

The following material is flagged Yellow Level. It contains material that is disputed by some experts but accepted by others. Caution is advised when deciding whether you personally choose to believe it.

So, some of you (especially the atheists among you) may have heard about Atheism+. Some of you (if there's even any of you who read this thing) may be wondering what my own position is on it.

I'm for it.

The "'Guys, Don't Do That' Incident" made it clear that the atheist movement has some problems when it comes to social justice issues. More recent events have shown that the problems are fairly pervasive. So, a new branch of the movement is necessary. If we want to be better than the religions we oppose, we must move beyond their mistakes. We must take an active stand against the traditions of bigotry that our societies have inherited from their religions. Otherwise, we are only better than they in that we know that evolution works and homeopathy doesn't.

As my first contribution to the movement (and in keeping with this blog's tendency to be Things I Find Interesting 101), I am posting some jargon for newcomers to the Atheism+ movement to help them understand discussions.

Note: If you can't find a term in its alphabetical section, look under "*" first, then go through the "Common variants" listing of similar terms.

*H*T: Acronym: (foo) Hurts (bar) Too. The fact that members of privileged groups can suffer as a result of the underlying systems resulting in their privilege, often as a result of deviation from the expectations of that system or the forbiddance thereof. See Also: MRA. Common variant: PHMT (Patriarchy, Men)
*ism: Institutionalized oppression of or bias against an unprivileged group by a society. Differs from the colloquial definition in that the bias or oppression must be systematic or institutionalized and must be supported by the society. Common variants: sexism, racism, ableism.
*splain: To assume that one's position of privilege grants one better knowledge of a subject than less privileged persons, and to attempt to educate them on the subject unasked, esp. on issues related to privilege and/or in defiance of statements that they already understand the subject. Not simply an explanation or correction to an error of fact issued while a member of a privileged group; *splaining must include an assumption without reason that a member of the non-privileged group is lacking in the knowledge presented, or, in the case of a dispute over a point of fact, an assumption without reason that a member of the non-privileged group is incorrect rather than oneself being in error. Common variants: mansplain, whitesplain, condesplain.
Atheism: A position of disbelief in deities. Ranges from lack of belief in a deity to belief that the existence of a deity is impossible. Typically associated with skepticism. 
Atheism+: 1. A position of belief that combines atheism and fully intersectional social justice. Usually includes a belief that the latter is necessary to or an inevitable conclusion of the former or that both are conclusions of skepticism. 2. A political and social movement based on def. 1, composed exclusively of persons accepting the position of belief but not containing all such persons.
Cisgender: Having an assigned gender role and anatomy at birth consistent with one's psychological gender and body image.
Egalitarianism: A belief that people should be treated equally; that every person should have an equal chance of success, however "success" is defined. Reasons for this vary from simple fairness to the idea that equality benefits everyone.
Intersectional:  Taking into consideration that multiple forms and types of prejudice and privilege may feed into or support one another. For instance, intersectional feminism is likely to take into consideration the ways in which misogyny and homophobia are connected.
Kyriarchy: The social structure that enforces privilege. Common variant: patriarchy.
LGBTIQAAN&C: Acronym: Lesbian, Gay, Bisexual, Transgender, Intersex, Queer/Questioning, Asexual, Agender, Nonconforming, and Cetera. Catch-all term for persons who do not fit the social norm of cisgender, heterosexual, and conforming to typical gender roles. Common variants: Too many to list, but most begin with LGBT or GLBT. Another common variant is QUILTBAG.
MRA: Acronym: Men's Rights Activist. Alternately formulated as Misogynist Raving *******. A person, often male, who believes that effects resulting from PHMT instead result from feminism, and who seeks to reverse the effects of the latter.
Microaggression: The most common manifestation of privilege and *ism. A seemingly-trivial decision, often unthinking, that due to being informed by *ist perspectives harms a member of an unpriviliged group. These decisions may even appear trivial to the person harmed, but add up to form larger problems.
PC: Acronym: Politically Correct. Common denigration of egalitarian movements and ideas, implying that they are a result of conformity to society. Contrasted with Politically Incorrect, which is often used to mask *ist attitudes as "thinking for oneself".
Prejudice: The act of making generalizations or unfounded assumptions about a group of people, typically harmful generalizations or assumptions about a non-privileged group. Often includes applying a generalization or assumption to each member of the group. Unlike *ism, prejudice can be against either privileged or unprivileged groups.
Privilege: A benefit or set of benefits socially granted to one group at the expense of another. Typically takes the form of traditions opposing one group, assumptions about a group or its individual members, and/or socioeconomic factors that for historical reasons place unequal pressures on a group or its members.  Opposed by egalitarianism and social justice. Note that lacking one type of privilege does not mean that one lacks all types; multiple types exist. Also note that simply having privilege is not in itself a negative trait and does not inherently make one's opinions worthless.
Privilege blindness: The tendency of a privileged individual, especially one new to social justice, to not be aware of privilege that has not been pointed out. May involve a belief that certain rights are "zero-sum", or that granting a right to a group currently lacking it will result in the denial of that right to a group currently possessing it; and may be accompanied by a belief that one's own lived experiences are universal. Note that being aware of one type of privilege does not make one aware of others.
Skepticism: A belief that knowledge is best obtained by rational inquiry and the scientific method. Typically associated with atheism.
Social Justice: A belief, almost always associated with egalitarianism, that a) people are not currently equal, and b) that the group most harmed by this should be harmed less or not at all. Typically, it is believed reducing the harm to the most-harmed group, or more accurately dismantling the socioeconomic structures causing the harm, will benefit all people.
Trigger:  1. n. A situation, including written descriptions of situations, that can result in stress responses in persons who have experienced the same or a similar situation. 2. v. To cause such a stress response. Common triggers include war, violence, and abuse.
TW: Acronym: trigger warning. See Also: trigger.
Xe: Gender-neutral pronoun, used for persons whose gender is unknown or neither male nor female. Common variants: ze, singular they. Possessive form: xir. Direct object form: xim.

Game Theory: Part III: Utility Functions

Now, a short digression (and a comic). How do you compare incomparables? If a life is measured against profits, which is valued higher?

The following material is flagged Green Level. It is intended to reflect material that the author believes to be a matter of consensus among experts in the field. This belief may be incorrect, however; and as the author is not an expert and does not have an expert fact-checking the article, errors may creep in.

 First, the comic.

Now, on to the digression. Suppose I offer you a choice between an apple and an orange.  (Yes, it's hardly a life compared to a work of art, but let's start small). We will say, for the purposes of this post, that you pick the apple.
According to game theory, this means that the apple has a higher utility value than the orange.
And there I go again, using terms. All people are assumed to have a utility function, which is a numerical measure of how much they like a given outcome. Utility functions, though, only work if certain conditions are met:
1) The function must be transitive. If an apple is better than an orange, and a pear is better than an apple, then a pear is better than an orange.
2) The function must be blind to gambling. An apple must be exactly as good as a one in two chance of two apples (assuming that two apples is exactly twice as good as one apple). In other words, the utility of a chance at an object is equal to that chance times the utility of the object.

So then, according to the economist, the utility of the Mona Lisa is equal to 872 times the utility of a human life. If he were faced with a choice between saving the Mona Lisa or saving 872 humans, both outcomes would be equal and he would likely flip a coin to decide.
<<Dominated Strategies | Game Theory | Non-Zero-Sum Games: Chicken>>

Topic: Game Theory

On this blog, I will sometimes discuss ideas over the course of multiple posts. I will call these ideas Topics, and collect them in posts like this one.

Game theory is a branch of mathematics dealing with the interactions between agents capable of making decisions. It provides understanding of how to benefit oneself as well as how to benefit both oneself and others, and can provide interesting insights into society.

1. Notation and Basic Concepts
2. Dominating Strategies
3. Utility Functions 
4. Non-Zero-Sum Games: Chicken 
5. Non-Zero-Sum Games: The Simple Prisoner's Dilemma 
6. Cyclic Games: The Iterated Prisoner's Dilemma I: Reciprocal Relationships 
7. Cyclic Games: The Iterated Prisoner's Dilemma II: The End of the Game.
8. Metagames: The Battle of the Sexes 
9. Coordination and Anti-Coordination 
10. Metagames: Extortion 
11. Metagames: The Punishing Prisoner's Dilemma 
12. Randomness 

Game Theory: Part I: Notation and Basic Concepts

Yes, evolution of cooperation, blah blah blah. I realized partway through that I needed some background material for that that I hadn't covered, and it's from a separate discipline. So let's start talking about game theory.

The following material is flagged Green Level. It is intended to reflect material that the author believes to be a matter of consensus among experts in the field. This belief may be incorrect, however; and as the author is not an expert and does not have an expert fact-checking the article, errors may creep in.

 So. What is this "game theory" thing? You may have heard some people talk about the "prisoners' dilemma" or the game of "chicken". Both of those are from game theory, which is essentially a branch of mathematics. And I will do my best to describe here how that works.
Let us suppose that you and I play a game. I will write down a letter (A or B) and you will try to guess it. If you guess correctly, I give you $1; if you guess incorrectly, you give me $1. This game can be represented as follows, where what you do is on the left, what I do is on the top, and what you get is in the intersection.

	A	B
A	$1	-$1
B	-$1	$1

(Incidentally,this is what is called a zero-sum game: if you get anything, it hurts me exactly as much as it helps you. Most real applications of game theory do not deal with zero-sum games, but they are the easiest to understand.)
So what, you ask. What does this have to do with the Real World? Well, suppose instead that the two of us are generals. Your force is strong, but mine is stealthy. If we send our armies to the same location, yours will stomp mine, but if we send them to different locations, mine will take the objective of the skirmish.
In essence, game theory is a subject with a broad variety of applications. Game theory can be applied to any situation (called a game) where 1) there are multiple players involved, 2) the actions of each player have an impact on the outcome for that player, and 3) the actions of each player have an impact on the outcomes for other players. This covers "games" ranging from "Guess the Letter" above to the games of "Crash the Economy" played on Wall Street.
To make this game a bit more interesting, let's add the following change: if you guess "B", the payment is doubled. The game now looks like this:

	A	B
A	$1	-$1
B	-$2	$2

Now, let's try to figure out what the best move for me to make is. Looking at the numbers, it looks like "A", right? If you guess wrongly, I win $2, but if you guess correctly, you win $1.
Wrong. Remember, you have a choice as well. Because you think I am likely to play "B", you choose to play "B". My payoff is -$1.
But let's say that I guess that you will reason that way, and choose to play "A". My payoff is now $1.
But then you anticipate my anticipation of your reasoning, and play "B". My payoff is now -$2. And so on to infinity. This is what makes game theory more than just an expected-value calculation: the non-random actions of another player.

So, how can we resolve this? Let's say that you manage to get a good look at what I write. This allows you to pick whatever I wrote. However, due to my psychic powers, I was able to know ahead of time that you would see it, and act accordingly. Thus, I choose to write the letter that will lose me the least (called my maximin solution), "A". You see that I have written "A", and guess "A", winning $1.

Alternately, let's say that you don't get a good look, but that I still have psychic powers. I know ahead of time what you are going to guess, and will write the letter that will gain me the most (called my minimax solution). But you know about my psychic powers, and choose to guess the letter that will lose you the least. Thus, you choose "B", forcing me to write "A". You lose $1.

<<First in Topic! | Game Theory | Dominating Strategies>>

Prediction regarding the UK

I had a realization about the riots in the UK.

The following material is flagged Violet Level.The author has seen something that gave him reason to retract the beliefs contained within, and only retains the posting for archival purposes.

It goes a bit like this: You know how they used to say that the revolution would not be televised? Well, in this age, that's about as far as you can get from the truth. The revolution will be televised. The revolution will be tweeted, blogged, radioed, and pamphlet-ed to within an inch of its life. The revolution will do this to itself, because the revolution must go viral to survive.

Do you remember what I said about evolution a while ago? As a refresher, there's a semi-controversial application of the theory called memetics. Memetics deals with the evolution of ideas, specifically ideas called memes that transmit themselves from one mind to another. In order to transmit themselves more effectively, some memes form structures called memeplexes (such as religions or political philosophies) in which each meme contributes to the survival and spread of others.

(It occurs to me that I need to write a post on the evolution of cooperation. Next time, maybe.)

So what does this have to do with television? Simple. Television, and other forms of mass media, are designed to transmit an idea from one person to a large number of people. Mass media allow memes and memeplexes to spread through a population much faster than simple word of mouth can carry them. So if one person has an idea, and that idea can be expressed in words or as an image or as a recording, that idea will start to spread faster once the meme hits a mass-media outlet.

And in the age of blogs, Twitter, and Facebook, everyone with an Internet connection is potentially a mass-media outlet.

And here's where the riots in the UK get into the post (warning: this is going to sound a bit Marxist, and the events described are a bit of an oversimplification). Once upon a time, there was a land called Egypt. The ruling parties of Egypt lived well, but the poor suffered and the middle-class was rapidly shrinking. Someone who was involved in a service operating in Egypt that allowed people to communicate got the idea of sparking some protests, just to see what would happen.

And happen things did! People started protesting the rulers. The rulers cracked down on these protests. This caused the protesters to begin protesting harder, and more people joined the protests. In time, the voice of the people was clearly organized against the rulers. The people of another land called the United States began to place pressure on their own ruler to assist the people of Egypt, and eventually managed it. In time, even the Egyptian army joined with the people, and the ruler was overthrown. The Egyptians began to draw up a new way of organizing their land, but there was some doubt as to whether or not the army could be trusted.

At the end of all this, things began to happen in yet another land called Great Britain. Britain had long had systems in place by which the poor were fed and the middle class protected, but ever since the reign of a leader named Thatcher these systems were being dismantled for the benefit of the rich. As the system by which the poor and the middle class could improve their stations was dismantled, riots began to break out. In response, the British judges began to place harsh sentences upon the rioters; the British government, like many governments, being heavily influenced by the rich.

Now, let us look at what is happening from a memetic standpoint.

One person working at Facebook, in the interest of SCIENCE!, distributed a meme, which we will call A. A, under specific conditions, led to revolts, creating a meme (B) in the minds of the rulers that caused them to crack down on the protests. However, the increased opposition led to the spread of A, and the increased spread of A strengthened B. This formed a simple pseudo-memeplex, in that memes held in different minds reinforced one another. In time, A grew to the point that it triggered a realization that it was the Voice of the People. Of course, this realization (C) itself became a meme. From that point, C exerted popularity pressure on various people's minds until the revolution succeeded (naturally eliminating B and making A temporarily irrelevant).

Of course, the success of the revolution was noticed by others, leading to a new meme (D) holding that revolution was possible. D is capable of forming memeplexes with any meme similar to A, and thus acts as a carrier for A and similar memes.

Then, some meme similar to A (possibly even A itself) landed in the mind of someone in Britain...

The whole point of this (and the prediction): The UK is going to be the next Egypt.

Link and cite: http://rationalwiki.org/wiki/Meme

On Evolution

More than once I have found myself arguing with creationists about the theory of evolution, so I will explain things here.

The following material is flagged Green Level. It is intended to reflect material that the author believes to be a matter of consensus among experts in the field. This belief may be incorrect, however; and as the author is not an expert and does not have an expert fact-checking the article, errors may creep in.

The Basics
First, let me explain what the theory of evolution actually says, since this is the most common point of disagreement. There are things (such as living beings, although a semi-controversial application of the theory called memetics posits that this can be expanded to include abstract information as well, and a type of robot called a von Neumann machine that constructs copies of itself would also count) that can "copy" themselves, which we will call replicators. Sometimes, when a replicator makes a copy of itself, it makes a small mistake, called a mutation. Sometimes, this mutation has no effect beyond possibly changing the effects of future mutations, such as a mutation in a set of "junk DNA" or in the comments of a piece of code. Sometimes, the mutation is neither harmful nor helpful, such as a change removing a vestigial organ. Sometimes, the mutation is harmful, such as a vertebrate forming without a DNA sequence coding for brain tissue. But sometimes, once in a great while, the mutation is actually useful, such as increasing how well the organism can process food.
Now, suppose that our mutant is in a place where its mutation is useful. Suppose that we're talking about a bear in a cold region that has fur better able to trap heat, or the like. That bear is going to find it a little bit easier to not freeze to death, and as such will have a slightly better chance of leaving copies of itself in the next generation of bears.
(As an aside, it is important to point out that a beneficial mutation is one that is beneficial in that specific environment. A bear with heat-trapping fur is at a disadvantage if taken to a place hot enough that water boils quickly, just as a heat-repelling one is at a disadvantage if taken to a place cold enough that all water is frozen. This will be important later on, when we talk about speciation. It will also be on the test, so I do hope you are taking notes.)
Now then, we have a bear in generation X with a 0.1% better ability to handle cold environments. This bear has a copy in generation X+1. Now, let us look at what that copy can do. Since it is a copy of the original bear, it also shares that 0.1% better ability. And if that bear manages to put copies in generation X+2, they will also share the improved ability to handle the cold, and so on. And eventually, those small chances add up. If in generation X+2 this improved ability saves one of the mutant bears, that means that there will be more of the bears with this ability in generation X+3. And this continues for a while.
But there is another factor: cold is not the only threat to the bears. Hunger is also a problem. Eventually, the bears hit a limit on the number that their food supply can support. With this limit in place, and the steadily growing number of bears able to handle cold, eventually the entire population of bears becomes able to handle the cold.
(Note that simple probability indicates that eventually, the bears with the higher survival rate would displace the bears with the lower survival rate, even if there were no population cap. This takes even longer, though.)


Irreducible Complexity
Now, let us assume that a second mutation shows up. This mutation repurposes the protein responsible for fur that grants resistance to cold so that when expressed in fur, it will still have its original purpose, but when expressed in blood, it will grant further cold resistance by the same amount. (Yes, I know that this specific for-instance has an incredibly low chance of actually making any kind of biological sense. But we're discussing hypothetical abstractions anyway, and it gets the point across.) So, the two mutations spread through the population at about the same rate, right?
Wrong. Remember that the second mutation works by repurposing the first. In bears that do not have heat-trapping fur, the mutation for cold-resisting blood will, at best, do nothing. At worst, it will repurpose some other protein, and do something very interesting to the bear's internal biochemistry. So, the cold-resisting-blood mutation can at best spread through the population at the same rate as one with a neutral effect, and at worst cannot spread beyond the subset of the population that has the heat-trapping-fur mutation. In other words, the mutation is of no beneficial effect without the one it modifies.
Next, suppose that, once the cold-resisting-blood mutation has become universal (and of course, the heat-trapping-fur mutation with it), a mutation happens in the heat-trapping-fur gene that causes it to function better, but only if the cold-resisting-blood gene is also present. (And at this point, the specific examples start approaching impossibility, but again: for-instances, hypothetical abstractions, gets the point across, et cetera.) Since the cold-resisting-blood gene is universal, the heat-trapping-fur-mark-2 mutation has no drawbacks. Since a heat-trapping-fur gene still exists (and can still be adapted for the purposes for which the cold-resisting-blood gene uses it), the system still works. And so, we have a system that is stable as it is, but which will fall apart if any component is removed.


Speciation
Now, let us suppose that the bears somehow split into two populations. Maybe the ice floes they live on are broken and begin drifting apart farther than the bears can swim. After millions of millions of generations, the bears build up a large number of mutations. Now, suppose that one mutation in one population is incompatible with another mutation in the other population. If those two mutations occur in the same individual, that individual will die off.
Contrary to how it may appear, this is not a disadvantage. As was mentioned above, a trait does not have to be beneficial in all situations in order to be beneficial; it only must be beneficial in the current situation. Similarly, it does not have to avoid being harmful in all situations in order to be harmless; it only must be harmless in the current situation. And the inability to breed with an individual one could not otherwise breed with is not a harmful trait. If the trait is beneficial (or even just allowed to spread over a few thousand more generations or so), the bears on the two floes will be separate species.


This will be continued later, after I have received some feedback on it. For now, this should cover the basics.

EDIT: I realized that I need to cover some more material, such as the evolution of cooperation. This will be discussed later.