In a recent Facebook post, Eliezer said :
You can believe that most possible minds within mind design space (not necessarily actual ones, but possible ones) which are smart enough to build a Dyson Sphere, will completely fail to respond to or care about any sort of moral arguments you use, without being any sort of moral relativist. Yes. Really. Believing that a paperclip maximizer won't respond to the arguments you're using doesn't mean that you think that every species has its own values and no values are better than any other.
And so I think part of the metaethics sequence went over my head.
I should re-read it, but I haven't yet. In the... (read 271 more words →)
An intuition is that red-black trees encode 2-3-4 trees (B-trees of order 4) as binary trees.
For a simpler case, 2-3 trees (Ie. B-trees of order 3) are either empty, a (2-)node with 1 value and 2 subtrees, or a (3-)node with 2 values and 3 subtrees. The idea is to insert new values in their sorted position, expand 2-nodes to 3-nodes if necessary, and bubble up the extra values when a 3-node should be expanded. This keeps the tree balanced.
A 2-3-4 tree just generalises the above.
Now the intuition is that red means "I am part of a bigger node." That is, red nodes represent the values contained in some higher black node.... (read more)