Another object view - (was RE: copy yourself ?)

Richard A. O'Keefe ok at cs.otago.ac.nz
Wed May 28 06:37:12 UTC 2003


Joel Shellman <joel at ikestrel.com> wrote:
	> Computational objects do not have mass;
	
	Of course they can:
	
	Transcript show: myMassiveObject mass.
	
No, that's not mass.
Abraham Lincoln is said to have originated this joke:

    X.  How many legs does a dog have,
        if you call a tail a leg?
    Y.  Five.
    X.  Wrong!  _Calling_ a tail a leg doesn't _make_ it a leg.

An object can respond to a #mass message, but it can do that as
often as you please, and it still will NOT have physical mass.

	> do not occupy space;
	
	Larger than we could possibly imagine (or smaller):
	
	Transcript show: myHugeObject volume.
	
Again, just because an object SAYS it has a volume doesn't mean it
DOES have a volume.  I'm not sure whether you are confusing
*talking about* properties with actually possessing them
(but no matter how often I _say_ "I have $1000000" it still isn't true)
or whether you are confusing *simulating* properties with actually
possessing them (but not matter how often I *pretend* to have a
million dollars it still isn't true).

	> do not emit or absorb photons (so don't have colour);
	
	Any in the rainbow, or in any spectrum::
	
	Transcript show: myColourfulObject color.
	or
	myColourfulObject emitPhoton.
	
The computer's screen can emit real photons.
An object in the image can only talk about or simulate emitting
photons.
	
Was it Drew McDermott who wrote "Just because your AI program has
a procedure called UNDERSTAND that doesn't mean it understands
anything."

	> Even in Morphic, which gives a pretty good illusion of
	> reality, if you "drop" a morph, it doesn't fall.
	
                                           vvvvvvvv
	It can do better than fall, it can simulate all sorts of potential behaviors
                                           ^^^^^^^^
	that would be "real" in any of a huge number of potential universes,
	including the one we're most familiar with.
	
"Simulate" is the key word here.

Nobody ever said that objects couldn't *simulate* real things.
Obviously they can.  Obviously it is often very very useful to do so.

But no matter how long you sit in the cockpit of a flight simulator,
you're never going to leave the room.  Simulated flight isn't real
flight.  Simulated mass isn't real mass.  Simulated falling isn't
real falling.

	It's all about simulation.

The whole POINT of simulation is that it is NOT REALITY, only LIKE it.

And my point is that vast amounts of computation are not about
simulating the physical world, so that for lots and lots of objects
there is no point in even trying to simulate physical objects.



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