Scenario:
1) You wake up in a bright box of light, no memories. You are told you'll presently be born into an Absolute monarchy, your role randomly chosen. You may choose any moral principles that should govern that society. The Categorical Imperative would on average give you the best result.
2) You are the monarch in that society, you do not need to guess which role you're being born into, you have that information. You don't need to make all the slaves happy to help your goals, you can just maximize your goals directly. You may choose any moral principle you want to govern your actions. The Categorical Imperative would not give you the best result.
A different scenario: Clippy and Anti-Clippy sit in a room. Why can they not agree on epistemic facts about the most accurate laws of physics and other Aumann-mandated agreements, yet then go out and each optimize/reshape the world according to their own goals? Why would that make them not rational?
Lastly, whatever Kant's justification, why can you not optimize for a different principle - peak happiness versus average happiness, what makes any particular justifying principle correct across all - rational - agents. Here come my algae!
You are the monarch in that society, you do not need to guess which role you're being born into, you have that information. You don't need to make all the slaves happy to help your goals, you can just maximize your goals directly. You may choose any moral principle you want to govern your actions. The Categorical Imperative would not give you the best result.
For what value of "best"? If the CI is the correct theory of morality, it will necessarily give your the morally best result. Maybe your complaint is that it wouldn't maximise your persona...
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A list of some posts that are pretty awesome
I recommend the major sequences to everybody, but I realize how daunting they look at first. So for purposes of immediate gratification, the following posts are particularly interesting/illuminating/provocative and don't require any previous reading:
More suggestions are welcome! Or just check out the top-rated posts from the history of Less Wrong. Most posts at +50 or more are well worth your time.
Welcome to Less Wrong, and we look forward to hearing from you throughout the site!
Note from orthonormal: MBlume and other contributors wrote the original version of this welcome post, and I've edited it a fair bit. If there's anything I should add or update on this post (especially broken links), please send me a private message—I may not notice a comment on the post. Finally, once this gets past 500 comments, anyone is welcome to copy and edit this intro to start the next welcome thread.