Pigliucci's comment on Yudkowsky's and Dai's stance on morality and logic

mapnoterritory

So morality has a lot to do with logic — indeed I have argued that moral reasoning is a type of applied logical reasoning — but it is not logic “all the way down,” it is anchored by certain contingent facts about humanity, bonoboness and so forth.

But, despite Yudkowsky’s confident claim, morality isn’t a matter of logic “all the way down,” because it has to start with some axioms, some brute facts about the type of organisms that engage in moral reasoning to begin with. Those facts don’t come from physics (though, like everything else, they better be compatible with all the laws of physics), they come from biology. A reasonable theory of ethics, then, can emerge only from a combination of biology (by which I mean not just evolutionary biology, but also cultural evolution) and logic.

http://rationallyspeaking.blogspot.de/2013/01/lesswrong-on-morality-and-logic.html

Pigliucci:

So morality has a lot to do with logic — indeed I have argued that moral reasoning is a type of applied logical reasoning — but it is not logic “all the way down,” it is anchored by certain contingent facts about humanity, bonoboness and so forth.

But, despite Yudkowsky’s confident claim, morality isn’t a matter of logic “all the way down,” because it has to start with some axioms, some brute facts about the type of organisms that engage in moral reasoning to begin with. Those facts don’t come from physics (though, like everything else, they better be compatible with all the laws of physics), they come from biology. A reasonable theory of ethics, then, can emerge only from a combination of biology (by which I mean not just evolutionary biology, but also cultural evolution) and logic.

http://rationallyspeaking.blogspot.de/2013/01/lesswrong-on-morality-and-logic.html

Massime explicitly denies reductionism, and Eliezer says that reductionism is the only good way to do philosophy. I'm not sure how you're getting a similarity.

They both tie ethics with the nature of humanlike creatures, but their structural-functional rather than physical nature.