Review
The standard argument is as follows:
Imagine Mahatma Ghandi. He values non-violence above all other things. You offer him a pill, saying "Here, try my new 'turns you into a homicidal manic' pill." He replies "No thank-you - I don't want to kill people, thus I also don't want to become a homicidal maniac who will want to kill people."
If an AI has a utility function that it optimizes in order to tell it how to act, then, regardless of what that function is, it disagrees with all other (non-isomorphic) utility functions in at least some places, thus it regards them as inferior to itself -- so if it is offered the choice "Should I change from you to to this alternative utility function ?" it will always answer "no".
So this basic and widely modeled design for an AI is inherently dogmatic and non-corrigible, and will always seek to preserve its goal. So if you use this kind of AI, its goals are stable but non-corrigible, and (once it becomes powerful enough to stop you shutting it down) you get only one try at exactly aligning them. Humans are famously bad at writing reward functions, so this is unwise.
Note that most humans don't work like this - they are at least willing to consider updating their utility function to a better one. In fact, we even have a word for someone who has this particular mental failing: 'dogmatism'. This is because most humans are aware that their model of how the universe works is neither complete nor entirely accurate - as indeed any rational entity should be.
Reinforcement Learning machines also don't work this way -- they're trying to learn the utility function to use, so they update it often, and they don't ask the previous utility function if that was a good idea since its reply will always be 'no' so is useless input.
There are alternative designs, see for example the Human Compatible/CIRL/Value Learning approach suggested by Stuart Russell and others, which is simultaneously trying to find out what its utility function should be (where 'should' is defined as 'humans would want it to be, but sadly are not good enough at writing reward functions to be able to tell me') so doing Bayesian updates to it as it gathers more information about what humans actually want, and also optimizing its actions while internally modelling its uncertainty about the utility of possible actions as a probability distribution of possible utilities for an action (i.e. it can model situations like "I'm about ~95% convinced that this act will just produce the true-as-judged-by-humans utility level 'I fetched a human some coffee (+1)', but I'm uncertain, and there's also an ~5% chance I current misunderstand humans so badly that it might instead have a true utility level of 'the extinction of the human species (-10^25)', so I won't do it, and will consider spawning a subgoal of my 'become a better coffee fetcher' goal to further investigate this uncertainty, by some means far safer than just trying it and seeing what happens." Note that the utility probability distribution contains more information than just its mean would: it can both be updated in a more Bayesian way, and optimized over in a more cautious way (for example, it you were optimizing over O(20) possible actions, you should probably optimize against a score of "I'm ~95% confident that the utility is at least this", so roughly two sigma below the mean if your distribution is normal - which it may well not be - to avoid building an optimizer that mostly retrieves actions for which your error bars are wide. Similarly if you're optimizing over O(10,000) possible actions, you should probably optimize the 99.99%-confidence lower bounds on utility, and thus also consider some really unlikely ways in which you might be mistaken about what humans want.
When I read posts about AI alignment on LW / AF/ Arbital, I almost always find a particular bundle of assumptions taken for granted:
My question: why assume all this? Most pressingly, why assume that the terminal goal is fixed, with no internal dynamics capable of updating it?
I often see the rapid capability gains of humans over other apes cited as a prototype case for the rapid capability gains we expect in AGI. But humans do not have this wrapper structure! Our goals often change over time. (And we often permit or even welcome this, whereas an optimizing wrapper would try to prevent its goal from changing.)
Having the wrapper structure was evidently not necessary for our rapid capability gains. Nor do I see reason to think that our capabilities result from us being “more structured like this” than other apes. (Or to think that we are “more structured like this” than other apes in this first place.)
Our capabilities seem more like the subgoal capabilities discussed above: general and powerful tools, which can be "plugged in" to many different (sub)goals, and which do not require the piloting of a wrapper with a fixed goal to "work" properly.
Why expect the "wrapper" structure with fixed goals to emerge from an outer optimization process? Are there any relevant examples of this happening via natural selection, or via gradient descent?
There are many, many posts on LW / AF/ Arbital about "optimization," its relation to intelligence, whether we should view AGIs as "optimizers" and in what senses, etc. I have not read all of it. Most of it touches only lightly, if at all, on my question. For example:
EY's notion of "consequentialism" seems closely related to this set of assumptions. But, I can't extract an answer from the writing I've read on that topic.
EY seems to attribute what I've called the powerful "subgoal capabilities" of humans/AGI to a property called "cross-domain consequentialism":
while defining "consequentialism" as the ability to do means-end reasoning with some preference ordering:
But the ability to use this kind of reasoning, and do so across domains, does not imply that one's "outermost loop" looks like this kind of reasoning applied to the whole world at once.
I myself am a cross-domain consequentialist -- a human -- with very general capacities to reason and plan that I deploy across many different facets of my life. But I'm not running an outermost loop with a fixed goal that pilots around all of my reasoning-and-planning activities. Why can't AGI be like me?
EDIT to spell out the reason I care about the answer: agents with the "wrapper structure" are inevitably hard to align, in ways that agents without it might not be. An AGI "like me" might be morally uncertain like I am, persuadable through dialogue like I am, etc.
It's very important to know what kind of AIs would or would not have the wrapper structure, because this makes the difference between "inevitable world-ending nightmare" and "we're not the dominant species anymore." The latter would be pretty bad for us too, but there's a difference!
Often people speak of the AI's "utility function" or "preference ordering" rather than its "goal."
For my purposes here, these terms are more or less equivalent: it doesn't matter whether you think an AGI must have consistent preferences, only whether you think it must have fixed preferences.
...or at least the AI behaves just as though this were true. I'll stop including this caveat after this.
Or possibly one big capacity -- "general reasoning" or what have you -- which contains the others as special cases. I'm not taking a position on how modular the capabilities will be.