I'd like to preface this one with a few important notes. Feel free to skip them:
First, I can almost guarantee that this post has been written before by someone much smarter and more learned than me.
Second, I have intentionally avoided searching for those essays which might shape my currently uncultivated perspective on the subject. As I've written before: the Barrier of Knowledge only goes one way, and once I know what other people think about something, I can't un-know it, and writing my own unique take would be a lot more difficult.
Third, I'm not a philosopher, and as such I'll probably make lots of illegal logical leaps, and those of you who know better will just have to forgive me, for I am willfully ignorant.
The study of ethics is an attempt to establish a cohesive moral framework. It's been a subject of debate for thousands of years, and for good reason! It's interesting, most everyone cares about it, and no two people completely agree. But at the heart of our disagreements concerning ethics is a larger disagreement concerning values, right? Some people value happiness above all else, so their moral code is structured around maximizing aggregate good. Others put life at the top of the list, making them willing to diminish its quality in order to preserve it. Still others set their god on the altar. Take your pick, but whatever you value most generally dictates your moral framework.
The theory of evolution is the idea that populations change from generation to generation. Often, these changes tend toward maximizing an organism's ability to survive in its environment. For example, over time, a species of bird might develop a naturally longer beak if that extra inch makes accessing their food easier. Birds with shorter beaks will get less food and die out over time. It should be noted that this is an extremely crude explanation of evolution, but it'll do the trick for today.
You've probably heard the term "survival of the fittest." I'm careful not to treat this as synonymous with the theory of evolution, but the two are definitely related. The idea is pretty explicitly stated in the phrase-- the fittest survive.
Now, I want you to accept something that probably isn't true. Ready?
Your survival is the most important thing.
At first, it's not all that disagreeable, but then you get into the scenario where it's your life versus the lives of a billion people, and it all starts to break down. But let's not go there. Let's just accept this one basic, fundamental value.
Your survival is the most important thing.
Now, how do we survive? Well, we've been told all of our lives that we need three things. What are they? Food, water, and shelter.
If my survival is the most important thing, then I'm going to need lots of food, lots of water, and lots of shelter. In fact, if my survival is the most important thing, then I'm going to take all of the food, water, and shelter that I can get.
Imagine a world in which everyone operated in this way. Unfortunately, it wouldn't be much different from our own, right? Living things act out of their own self-interest daily, and the most efficient way to get food, water, and shelter in our world is not to collect it directly-- it's to amass currency and buy it. But if the universe has a fixed amount of resources, then we can't really produce or generate this currency, we have to take it. That's why there are rich people and poor people. Every dollar I earn is a dollar out of someone else's pocket. Collecting valuable resources is no joke, and it often seems we humans will do whatever it takes.
What if that's okay? No, what if that's required?
What if your survival is the most important thing?
Then that's what we should base our moral framework on! Right? In this world we've imagined, it's not happiness or life in general, it's not some god, it's your survival upon which morality should be built. Now, you have a moral obligation to accumulate food, water, and shelter, and every crumb of food, drop of water, and block of shelter that you horde is a crumb, drop, or block that someone else is deprived of. And that's okay. Why?
Because your survival is the most important thing.
That's sick, right? I'm morally obligated to deprive people of what they need to survive? That's a world that I certainly don't want to live in.
But what if it is the world you live in?
If all of your features are just the result of favorable, random mutation, and your reason for being is because your species was fit enough to survive, if every bit of you, down to your opposable thumbs and your hairy nose is the way it is because at some point in evolutionary history it gave you an advantage over your thumbless, hairless cousin, then doesn't that point to that lie I told you to accept earlier? That your survival is the most important thing?
If biology is the driver, then I'm sorry, but your survival is the most important thing, and your ability to reason beyond that purpose is just an artifact of the very vehicle that got you here.
Am I crazy? Is that not the logical conclusion of a universe driven by survival? Is the building up of self, even at the expense of others not the highest call of a morality founded in the most basic principles of evolutionary theory?
The fittest tend to survive. That's a fact of life, and I fear that that fact, in the absence of some other moral absolute, demands that your survival is the most important thing and that the pursuit of that end is the only believable ethical framework.