From: Dan Clemmensen (dgc@shirenet.com)
Date: Wed Sep 25 1996 - 17:41:22 MDT
N.BOSTROM@lse.ac.uk wrote:
>
> Dan Clemmensen has suggested that SIs don't colonise cosmos
> because of their high discount rate for future benefits. The
> discount rate would presumably be high because of the
> rapidity of their subjective time and the slowness of cosmic
> travels. The idea is interesting since, if right, it would
> help resolve the Fermi paradox.
>
> One reason why SIs could have a high discount rate would be
> if they had a bias towards the near future, just as we
> humans have. We tend to care more about an imminent pleasure
> than about a similar one we would sure to get in a billion
> years. Perhaps all SIs would be "irrational" in the same
> way?
>
> Another reason why an SI might discount the benefits of
> colonisation is because they would only come about if it
> diverted some of its resources to the space mission,
> resources which could have been used for other purposes.
> Suppose that the objective of the SI is to maximise the
> amount of valuable computations it will carry out during its
> life time. At a certain time t it has a given capital
> (consisting perhaps of its mass or available energy). Part
> of this capital could be invested into a project that would
> yield returns at t'>t, but meanwhile that capital could not
> be used to make valuable computations, i.e. there would be
> an opportunity cost which would have to be subtracted from
> the expected returns when considering whether the investment
> is worthwhile. The question is what the function
> f=valuablecomputationspower(capital) looks like. For
> Clemmensen's argument to go through, it would not suffice
> that f had a jerk at some point, because different SIs would
> presumably start out with somewhat different amounts of
> capital. If all SI had originally a capital less that the
> critical amount, then they would invest in space missions,
> but the benefit of space missions seems to come in chunks
> (one chunk for every planet or solar system one arrived at),
> and so there would be some overshoot: most SIs would obtain
> a capital greater than the critical value, and they would
> have little to lose from using the excess for new space
> missions. f would rather have to have the shape of an
> inverted exponential, so that for each amount of capital
> (greater than some start-up value), a slight loss of capital
> would reduce the computation power greatly, whereas a slight
> increase would bring but a negligible increase. Not only
> would the function have to be of an exponential character,
> the constants would have to be rather great, considering
> that the gains would be obtained after perhaps a thousand
> years and be enjoyed for perhaps billions of years, while
> the required investment would presumably be very small
> compared to the SI's total capital whereas the gains could
> be very substantial. For instance, if any considerable
> degree of parallelization of valuable computations were
> possible, then df/d(capital) would certainly not decrease
> rapidly enough.
>
> If Robin's objection, that not all knowledge can be obtained
> simply by sitting back and think (making computations), is
> directed against Clemmensen's basic idea rather than against
> some other more specific claim Clemmensen has made, then I
> don't think it carries very much weight, because there is no
> obvious reason why SIs should be interested in the detailed
> structure of distant cosmic regions. We must not forget that
> a mere suggestion for where the Great Filter could be, even
> if it falls short of being a proof, would be very helpful;
> in any case there seem to be much greater difficulties with
> Clemmensen's proposal than that it assumes that the
> curiosity of SIs is rather limited.
>
> Nicholas Bostrom n.bostrom@lse.ac.uk
This is a good description of the the disscussion Robin and I are
having. I'd like ot clarify a few points, however.
1) I do not really believe SI's will act as I have described. I believe
that
SI's motivations are incomprehensible to us. I was, as you suggested,
trying
to examine one possible element of the "great filter". Your points deal
with
the liklihood that this element is important. The actual filter is the
more general possibility that SIs will choose not to explore for a
reason that
is generis to the condition of being an SI. The "computational discount
rate" was
intended only as an example.
More later. I have to go do a kid taxi run.
This archive was generated by hypermail 2.1.5 : Fri Nov 01 2002 - 14:35:45 MST