There are those who will see it as almost a religious principle that no one can possibly know that a design will work, no matter how good the argument, until it is actually tested. Just like the belief that no one can possibly accept a scientific theory, until it is tested. But this is ultimately more of an injunction against human stupidity and overlooked flaws and optimism and self-deception and the like - so far as theoretical possibility goes, it is clearly possible to get a pretty damn good idea of which designs will work in advance of testing them.
I see a difference between "know" and "pretty damn good idea." This looks like a failed sub-argument in an otherwise successful and inspirational argument.
Also, there's the possibility that the relevant thing that is tested is not just "which of these designs work better?" but "is my best attempt good enough to trust or do I need to spend more resources/give up?".
Today's post, Building Something Smarter was originally published on 02 November 2008. A summary (taken from the LW wiki):
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This post is part of the Rerunning the Sequences series, where we'll be going through Eliezer Yudkowsky's old posts in order so that people who are interested can (re-)read and discuss them. The previous post was Mundane Magic, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
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