According to Eliezer's definition of "should" in this post, I "should" do things which lead to "life, consciousness, and activity; health and strength; pleasures and satisfactions of all or certain kinds; happiness, beatitude, contentment, etc.; truth; knowledge and true opinions of various kinds, understanding, wisdom; beauty, harmony, proportion in objects contemplated; aesthetic experience..." But unless I already cared about those things, I don't see why I would do what I "should" do, so as a universal prescription for action, this definition of "morality" fails.