Comment author: Alerus 07 May 2012 08:16:50PM 3 points [-]

It's hard for me to gauge your audience, so maybe this wouldn't be terribly useful, but a talk outlining logical fallacies (especially lesser-known ones) and why they are fallacies seems like it would have a high impact since I think the layperson commits fallacies quite frequently. Or should I say, I observe people committing fallacies more often than I'd like :p

Comment author: Alerus 07 May 2012 03:48:56PM 5 points [-]

Hi! So I've actually already made a few comments on this site, but had neglected to introduce myself so I thought I'd do so now. I'm a PhD candidate in computer science at the University of Maryland, Baltimore County. My research interests are in AI and Machine Learning. Specifically, my dissertation topic is on generalization in reinforcement learning (policy transfer and function approximation).

Given this, AI is obviously my biggest interest, but as a result, my study of AI has led me to applying the same concepts to human life and reasoning. Lately, I've also been thinking more about systems of morality and how an agent should reach rational moral conclusions. My knowledge of existing working in ethics is not profound, but my impression is that most systems seem to be at too high a level to make concrete (my metric is whether we could implement it in an AI; if we cannot, then it's probably too high-level for us to reason strongly with it ourselves). Even desirism, which I've examined at least somewhat, seems to be a bit too high-level, but is perhaps closer to the mark than others (to be fair, I may just not know enough about it). In response to these observations, I've been developing my own system of morality that I'd like to share here in the near future to receive input.

Comment author: Alerus 07 May 2012 02:22:27PM *  0 points [-]

I disagree with the quoted part of the post. Science doesn't reject your bayesian conclusion (provided it is rational), it's simply unsatisfied by the fact that it's a probabilistic conclusion. That is, probabilistic conclusions are never knowledge of truth. They are estimations of the likelihood of truth. Science will look at your bayesian conclusion and say "99% confident? That's good!, but lets gather more data and raise the bar to 99.9%!). Science is the constant pursuit of knowledge. It will never reach it it, but it will demand we never stop trying to get closer.

Beyond that, I think in a great many cases (not all) there are also some inherent problems in using explicit bayesian (or otherwise) reasoning for models of reality because we simply have no idea what the space of hypotheses could be. As is such, the best bayesian can ever do in this context is give an ordering of models (e.g., this model is better than this model), not definitive probabilities. This doesn't mean science rejects correct bayesian reasoning for the reason previously stated, but it would mean that you can't get definitive probabilistic conclusions with bayesian reasoning in the first place for many contexts.

Comment author: momothefiddler 07 May 2012 12:48:36AM 0 points [-]

I like this idea, but I would also, it seems, need to consider the (probabilistic) length of time each utility function would last.

That doesn't change your basic point, though, which seems reasonable.

The one question I have is this: In cases where I can choose whether or not to change my utility function - cases where I can choose to an extent the probability of a configuration appearing - couldn't I maximize expected utility by arranging for my most-likely utility function at any given time to match the most-likely universe at that time? It seems that would make life utterly pointless, but I don't have a rational basis for that - it's just a reflexive emotional response to the suggestion.

Comment author: Alerus 07 May 2012 01:23:08PM 0 points [-]

Yeah I agree that you would have to consider time. However, my feeling is that for the utility calculation to be performed at all (that is, even in the context of a fixed utility), you must also consider time through the state of being in all subsequent states, so now you just add and expected utility calculation to each of those subsequent states (and therefore implicitly capture the length of time it lasts) instead of the fixed utility. It is possible, I suppose, that the probability could be conditional on the previous state's utility function too. That is, if you're really into math one day it's more likely that you could switch to statistics rather than history following that, but if you have it conditioned on having already switched to literature, maybe history would be more likely then. That makes for a more complex analysis, but again, approximations and all would help :p

Regarding your second question, let me make sure I've understood it correctly. You're basically saying couldn't you change the utility function, what you value, on the whims of what is most possible? For instance, if you were likely to wind up stuck in a log cabin that for entertainment only had books on the civil war, that you change your utility to valuing civil war books? Assuming I understood that correctly, if you could do that, I suppose changing your utility to reflect your world would be the best choice. Personally, I don't think humans are quite that malleable and so you're to an extent kind of stuck with who you are. Ultimately, you might also find that some things are objectively better or worse than others; that regardless of the utility function some things are worse. Things that are damaging to society, for instance, might be objectively worse than alternatives because the consequential reproductions for you will almost always be bad (jail, a society that doesn't function as well because you just screwed it up, etc.). If true, you still would have some constant guiding principles, it would just mean that there are a set of other paths that are in a way equally good.

Comment author: Alerus 06 May 2012 06:02:35PM *  0 points [-]

So it seems to me that the solution is use an expected utility function rather than a fixed utility function. Lets speak abstractly for the moment, and consider the space of all relevant utility functions (that is, all utility functions that would change the utility evaluate of an action). At each time step, we now will associate a probability of you transitioning from your current utility function to any of these other utility functions. For any given future state then, we can compute the expected utility. When you run your optimization algorithm to determine your action, what you therefore do is try and maximize the expected utility function, not the current utility function. So the key is going to wind up being assigning estimates to the probability of switching to any other utility function. Doing this in an entirely complete way is difficulty I'm sure, but my guess is that you can come to reasonable estimates that make it possible to do the reasoning.

Comment author: Alerus 25 December 2011 04:03:00PM 0 points [-]

I think you may be partitioning things that need not necessarily be partitioned and it's important to note that. In the nicotine example (or the "lock the refrigerator door" example in the cited material), this is not necessarily a competition between the wants of different agents. This apparent dichotomy can also be resolved by internal states as well as utility discount factors.

To be specific, revisit the nicotine problem. When a person decides to quit they may not be suffering any discomfort so the utility of smoking at that moment is small. Instead then, the eventual utility of longer life wins out and the agent decides to stop smoking. However, once discomfort sets in, it combines with the action of smoking because smoking will relieve the discomfort. Now the individual still has the other utility assigned to not dying sooner (which would favor the "don't smoke" action). However, the death outcome will happen much later. Even though death is far worse than the current discomfort being felt (assuming a "normal" agent ;), so long as the utilities also operate on a temporal discount factor, that utility may be reduced to be smaller than the utility of smoking that will remove the current discomfort due to how much it gets discounted from it happen much further in the future.

At no point have we needed to postulate that these are separate competing agents with different wants and this seeming contradiction is still perfectly resolved with a single utility function. In fact, wildly different agent behavior can be revealed by mere changes in the discount factor for enumerable reinforcement learning (RL) agents where discount and reward functions are central to the design of the algorithm.

Now, which answer to the question is true? Is the smoke/don't smoke contradiction a result of competing agents or discount factors and internal states? I suppose it could be either one, but it's important to not assume that these examples directly indicate that there are competing agents with different desires, otherwise you may lose yourself looking for something that isn't there.

Of course, even if we assume that there are competing agents with different desires, it seems to me this still can be, at least mathematically, reduced to a single utility function. All it means, is that you apply weights to the utilities of different agents, and then standard reasoning mechanisms are employed.

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