> Jonathan Colvin writes, regarding the Doomsday argument:
> > There's a simple answer to that one. Presumably, a million
> years from
> > now in the Galactic Empire, the Doomsday argument is no longer
> > controversial, and it will not be a topic for debate. The
> fact that we
> > are all debating the Doomsday argument implies we are all
> part of the
> > reference class: (people debating the doomsday argument), and we
> > perforce can not be part of the Galactic Empire.
> Well, I don't want to open up discussion of the DA. Suffice
> it to say that good thinkers have spent considerable amounts
> of time considering it and don't necessarily think that this
> reply puts it to bed.
> http://www.anthropic-principle.com has an exhaustive discussion.
Since it is coming from Nick B., over-exhaustive :)
I don't think anybody, Nick included, has yet come up with a convincing way
to define appropriate reference classes. Absent this, the only way to rescue
the DA seems to be a sort of dualism (randomly emplaced souls etc).
> [Regarding measure and size]
> > I find these conclusions counter-intuitive enough to suggest that
> > deriving measure from a physical fraction of involved reasources is
> > not the correct way to derive measure. It is not unlike trying to
> > derive the importance of a book by weighing it.
> Don't be too eager to throw out this concept of measure. It
> is fundamental to the Schmidhuber and Tegmark approach to the
> It allows deriving why induction works as well as Occam's razor.
> It explains why the universe is lawful and has a simple description.
> It allows us in principle to calculate how likely we are to
> be in The Matrix or some such simulation vs a basement-level
> universe. It is quite an amazing quantity of results from
> such a simple assumption.
> I don't think you will find anything else like it in philosophy.
> As far as the specific issue of measure and size, suppose you
> agree that making copies of a structure increases its
> measure, but you object to the idea that scaling up its size
> would do so. Years ago I came up with a thought experiment
> that adopted the position you have, that size doesn't matter.
> (That's what my wife kept telling me, after all...) From
> that I proved that copies didn't matter either, which wasn't
> too appealing. Today I would say that my premise was wrong.
> Size matters.
Isn't there a counter argument, though? Imagine a Universe of size X, and
that observers have size Y<X. As Y increases towards X, the number of
possible observers in the Universe decreases, until at the limit Y=X a
universe can contain only one observer. Conversely, the smaller the Y, the
more observers the universe can contain (and presumably the larger the
measure). On this argument, *decreasing* our size should increase our
measure (in the same way that smaller universes have greater measure).