He didn't say other architectures would be no good, he said they're less likely to be safe.
He thinks the distribution P(Outcome | do(complete Oracle AI project)) isn't as highly peaked at Weirdtopia as P(outcome | do(complete FAI)); Oracle AI puts more weight on regions like "Lifeless universe", "Eternal Torture", "Rainbows and Slow Death", and "Failed Utopia".
However, "Complete FAI" isn't an actionable procedure, so he examines the chance of completion conditional on different actions he can take. "Not worth pursuing because non-implementable" means that available FAI supporting actions don't have a reasonable chance of producing friendly AI, which discounts the peak in the conditional outcome distribution at valuable futures relative to do(complete FAI). And supposedly he has some other available oracle AI supporting strategy which fares better.
Eating a sandwich isn't as cool as building an interstellar society with wormholes for transportation, but I'm still going to make a sandwich for lunch, because it's going to work and maybe be okay-ish.
Suppose you buy the argument that humanity faces both the risk of AI-caused extinction and the opportunity to shape an AI-built utopia. What should we do about that? As Wei Dai asks, "In what direction should we nudge the future, to maximize the chances and impact of a positive intelligence explosion?"
This post serves as a table of contents and an introduction for an ongoing strategic analysis of AI risk and opportunity.
Contents:
Why discuss AI safety strategy?
The main reason to discuss AI safety strategy is, of course, to draw on a wide spectrum of human expertise and processing power to clarify our understanding of the factors at play and the expected value of particular interventions we could invest in: raising awareness of safety concerns, forming a Friendly AI team, differential technological development, investigating AGI confinement methods, and others.
Discussing AI safety strategy is also a challenging exercise in applied rationality. The relevant issues are complex and uncertain, but we need to take advantage of the fact that rationality is faster than science: we can't "try" a bunch of intelligence explosions and see which one works best. We'll have to predict in advance how the future will develop and what we can do about it.
Core readings
Before engaging with this series, I recommend you read at least the following articles:
Example questions
Which strategic questions would we like to answer? Muehlhauser (2011) elaborates on the following questions:
Salamon & Muehlhauser (2013) list several other questions gathered from the participants of a workshop following Singularity Summit 2011, including:
These are the kinds of questions we will be tackling in this series of posts for Less Wrong Discussion, in order to improve our predictions about which direction we can nudge the future to maximize the chances of a positive intelligence explosion.