Barring a major collapse of human civilization (due to nuclear war, asteroid impact, etc.), many experts expect the intelligence explosion Singularity to occur within 50-200 years.
That fact means that many philosophical problems, about which philosophers have argued for millennia, are suddenly very urgent.
Those concerned with the fate of the galaxy must say to the philosophers: "Too slow! Stop screwing around with transcendental ethics and qualitative epistemologies! Start thinking with the precision of an AI researcher and solve these problems!"
If a near-future AI will determine the fate of the galaxy, we need to figure out what values we ought to give it. Should it ensure animal welfare? Is growing the human population a good thing?
But those are questions of applied ethics. More fundamental are the questions about which normative ethics to give the AI: How would the AI decide if animal welfare or large human populations were good? What rulebook should it use to answer novel moral questions that arise in the future?
But even more fundamental are the questions of meta-ethics. What do moral terms mean? Do moral facts exist? What justifies one normative rulebook over the other?
The answers to these meta-ethical questions will determine the answers to the questions of normative ethics, which, if we are successful in planning the intelligence explosion, will determine the fate of the galaxy.
Eliezer Yudkowsky has put forward one meta-ethical theory, which informs his plan for Friendly AI: Coherent Extrapolated Volition. But what if that meta-ethical theory is wrong? The galaxy is at stake.
Princeton philosopher Richard Chappell worries about how Eliezer's meta-ethical theory depends on rigid designation, which in this context may amount to something like a semantic "trick." Previously and independently, an Oxford philosopher expressed the same worry to me in private.
Eliezer's theory also employs something like the method of reflective equilibrium, about which there are many grave concerns from Eliezer's fellow naturalists, including Richard Brandt, Richard Hare, Robert Cummins, Stephen Stich, and others.
My point is not to beat up on Eliezer's meta-ethical views. I don't even know if they're wrong. Eliezer is wickedly smart. He is highly trained in the skills of overcoming biases and properly proportioning beliefs to the evidence. He thinks with the precision of an AI researcher. In my opinion, that gives him large advantages over most philosophers. When Eliezer states and defends a particular view, I take that as significant Bayesian evidence for reforming my beliefs.
Rather, my point is that we need lots of smart people working on these meta-ethical questions. We need to solve these problems, and quickly. The universe will not wait for the pace of traditional philosophy to catch up.
A 'reason for action' is the standard term in Anglophone philosophy for a source of normativity of any kind. For example, a desire is the source of normativity in a hypothetical imperative. Others have proposed that categorical imperatives exist, and provide reasons for action apart from desires. Some have proposed that divine commands exist, and are sources of normativity apart from desires. Others have proposed that certain objects or states of affairs can ground normativity intrinsically - i.e. that they have intrinsic value apart from being valued by an agent.
A source of normativity (a reason for action) is anything that grounds/justifies an 'ought' or 'should' statement. Why should I look both ways before crossing the street? Presumably, this 'should' is justified by reference to my desires, which could be gravely thwarted if I do not look both ways before crossing the street. If I strongly desired to be run over by cars, the 'should' statement might no longer be justified. Some people might say I should look both ways anyway, because God's command to always look before crossing a street provides me with reason for action to do that even if it doesn't help fulfill my desires. But I don't believe that proposed reason for action exists.
If you want to be run over by cars, you should still look both ways.
You might miss otherwise!