TP:
That which can exist will exist - the fundamental metaphysical principle of life. Once life exists, it enters into the game of existence - how to survive and reproduce? Just as there are objectively good and bad ways to play a game of chess, there are objectively good and bad ways to play the game of life. The ways to play the game of life are called "morality" and we can measure the quality of a moral system with game theory.
INTERLOCUTOR:
If objective list theorists and hedonists who think that claims like "a happy life is better than a miserable one for the being who lives it" are correct, then game theory can help us achieve that goal, but can it tell us that that goal is worthwhile in the first place? If it can, how, if it can't, then it seems to miss the point.
TP:
Who has the authority for determining whether a goal is worthwhile or not? If creatures determine if goals are worthwhile, then evolution (via game theory) will craft the definition of what a worthwhile goal is.
INTERLOCUTOR:
 It seems to me that some value judgements can be correct and some can be mistaken. Wouldn't someone who thought that living a short and miserable life would be better for them than living a long and happy one be making some kind of mistake? I don't think we need an authority figure to help us work these things out. We can do it ourselves.
TP:
I agree! We are our own authority for determining morality. Each time we analyze a trolley problem or a philosophic dilemma, we are appealing to the moral authority of our intuitions. Our intuitions were given to us by evolutionary game theory - for the objective purpose of winning the game of life.
INTERLOCUTOR:
How then could we get our value judgements wrong? If Harry genuinely thought, as a matter of psychological fact, that a short and miserable life was better for him than a long and happy one, wouldn't he be mistaken? Parfit uses the example of someone he calls Crimson who has such a bad case of near-term bias that he genuinely prefers; i.e. thinks it's best for him to avoid a few minutes mild discomfort later today even though he knows that it will result in him experiencing an hour of full-blown agony tomorrow. Wouldn't such a person be getting something wrong?
TP:
Happiness and misery - what is their evolutionary root? Happiness is a signal of the accrual of positive evolutionary points - things that help you win the game. Misery is a signal of the accrual of negative evolutionary points - things that make you lose the game. If one's actions are causing them to objectively lose the game (misery) then it is objectively wrong to pursue that strategy, i.e. immoral, all else being equal (no mitigating factors like a moral reason to pursue the misery).
Same thing with Crimson - the objectively correct thing to do is accrue the evolutionary points in an unbiased way. To be biased is to be inaccurate (and errant) in one's strategy.
INTERLOCUTOR:
Pain often serves a useful purpose warning us of danger, so it can have instrumental value if we want to avoid danger, though it serves no purpose for Crimson. We seem to agree that happiness is better than misery, but not about the reason why. I think it's the nature of the subjective experience of happiness and misery that gives all sentient beings a reason to seek the former and avoid the latter. Survival and procreation don't seem to have any inherent value to me. They only have instrumental value because they serve to enable lives with a preponderance of happiness over misery. If we know that a life will be full of suffering and misery, then don't we have a reason to either prevent it or to end it?
TP:
Survival and procreation don't seem to have any inherent value to me either, but they are the reason I have the moral system and wellbeing system that I have. Wellbeing is naturally sufficient as a moral foundation because wellbeing is the way evolution communicates game theory to us.
A crucial point is that evolutionary pressures operate on genes, not individuals. The sacrifice of one individual for the benefit of the group is perfectly evolutionarily coherent.
If we suffer to the point of desiring suicide, then perhaps that means that our environment is not very suitable for the thriving of humans, perhaps there are too many humans and not enough resources for the flourishing of those humans, and that maybe less humans are needed so that the group (genes) can survive through a tough resource bottleneck. Suicide then might be a voluntary means of population control for the group.
INTERLOCUTOR:
I don't understand how game theory tells us what we have most reason to want in the first place. Once we've chosen a goal, then it can lend a hand in helping us achieve that goal. Many of our moral intuitions are the result of evolutionary pressures. I suspect that the widespread condemnation of homosexuality across time and culture is the result of survival tracking intuitions. Same sex attracted people were probably less likely to pass on their genes to future generations than opposite sex attracted people. This may have led to many people having a 'yuck' response to same-sex activity which morphed from 'yuck' into 'wrong'. If we assume that such intuitions have survival tracking benefits that encourage reproductive success, that doesn't make them 'moral', does it?
TP:
Well, I view morality as an all inclusive set of all possible moralities. Each moral perspective is an instance of a type of morality within the set of all moralities.
Given this set, each type of morality can be rank ordered by game theoretic successfulness. People who have a 'yuck' response think they are being moral based on their morality. But the question is - is that 'yuck' response truly game theoretically optimal? Or is it a suboptimal moral response? As the environment shifts, optimal morality shifts. Perhaps in ancient times, dogmatic forced birthing was optimal, but it is not likely to be optimal now that we are approaching 8 billion people on the planet.
INTERLOCUTOR:
What is "theoretic success"? Is it based in the likelihood a given theory has in achieving "success"? If it is, then what is "success"? Survival? Procreation? Happiness? (I'd opt for that last option.)
TP:
Imagine a hypothetical future where only China and the USA are competing. The Chinese are evolving a moral acceptance towards tyranny. The Americans are evolving a moral revulsion towards tyranny. Consequently, China adopts the authoritarian strategy and America adopts the freedom strategy. Imagine that America self-destructs into bloody anarchy. The only nation to survive is China. Morality begins to shift towards that which is more optimal for survival. The future will be full of people who are morally okay with tyranny. The ability to survive defines what is moral by virtue of its ability to succeed in the game of life. Happiness has no causal role on the definition of morality. Happiness is a second-order communication of that which a creature is programmed to like. Only the creatures who like the right thing will exist into the future, and carry their definition of morality forward.
INTERLOCUTOR:
Thanks for explaining. I understand now where we disagree. I don't think that survival matters in any fundamental sense, nor do I think that the winner in a battle between political ideologies is somehow more "moral" because it is more successful. Happiness matters, suffering matters, procreative and political success only have instrumental value insofar as they serve to promote wellbeing or reduce suffering.
TP:
What is your meta-ethical justification for that view though?