Evolutionary ethics is a topic that I've
mostly avoided to date. It's not because I don't think it is relevant, or I'm not interested, or I don't have much to say about the topic - rather it is down to "sociological" factors.
Briefly: evolutionary ethics is a large and fascinating topic. It appears to be in rapid ascent recently - with many books being published on the topic. I think this is a good thing.
For a long time, the ethical naturalism was widely treated with scorn - under the title of "the naturalistic fallacy" and the open question argument.
Of course, the idea that "you can't get ought from is" is a silly one - if you can't get to "ought" from "is", then you can't get to "ought" at all - and yet we see plenty of "ought" in the world.
Naturalistic approaches to ethics typically treat "oughts" as representing the preferences of some agent (possibly imaginary). The idea that 'good' is universal is typically ditched - though agents can have convergent preferences in some areas.
An interest in ethics serves many biological functions. Among them, ethics represents:
- A guide to individuals about how to behave;
- A guide to expected behaviour - to avoid sanctions;
- A tool for manipulating the behaviour of others;
- A signalling system, for virtue signalling;
Evolutionary theory (including some game theory) pretty comprehensively explains the origins of all goal-directed behaviour. It's the main science that explains the existence of optimization in nature. Cases where physics appears to directly involve optimization (such as lightning strikes finding the highest point) are actually well-explained by evolutionary theory. It thus neatly covers "descriptive ethics".
However, this leaves normative ethics and meta ethics - which have typically been regarded as philosophical subjects divorced from science. That is not an acceptable resolution - it just shoves ethics down the science-nonsense divide.
Much evolutionary ethics falls into the broad category of "survivalism". However, survivalism leaves open the issue of what is trying to survive. Evolutionary ethics explains some types of ethical behaviour in terms of survival of genes - and other types of evolutionary in terms of survival of memes. Issues to do with multi-level selection are also left somewhat open to interpretation. Some argue that group-level survival is more closely associated with moral behaviour than individual-level survival is.
Sam Harris wrote a book about a naturalistic approach to ethics fairly recently. His effort seemed rather embarrassing to me - this is not what most naturalistic ethics looks like.
My own avoidance of evolutionary ethics has multiple roots. It's a popular topic; others are attracted to it, making my contributions less significant. It's a noisy and controversial topic; when I do discuss it, there are often noisy and confused debates, which I have limited time for these days. Lastly, a concern for moral issues is typically used as a signalling device: to tell others what a fine fellow you are. This introduces a complicated level of double-talk into many discussions of the topic. Frankly, this is a turn-off for me. If I talk about ethical naturalism, it's mainly because I am interested in the science involved. I'm not very interested in the moral "pissing-contests" and "holier-than-thou" attitudes that tend to surround the topic - except in terms of quantifying them as sources of noise.