Re: Many Pasts? Not according to QM...

From: Hal Finney <hal.domain.name.hidden>
Date: Fri, 27 May 2005 22:21:52 -0700 (PDT)

Stathis Papaioannou writes:
> More generally, if a person has N OM's available to him at time t1 and kN at
> time t2, does this mean he is k times as likely to find himself experiencing
> t2 as t1? I suggest that this is not the right way to look at it. A person
> only experiences one OM at a time, so if he has "passed through" t1 and t2
> it will appear to him that he has spent just as much time in either interval
> (assuming t1 and t2 are the same length). The only significance of the fact
> that there are "more" OM's at t2 is that the person can expect a greater
> variety of possible experiences at t2 if the OM's are all distinct.

It's a good puzzle. Some time back I expressed it as follows: suppose
the measure of the even days of my life were arranged to be twice as
good as the measure of the odd days. How would I notice this? Would I
somehow be more likely to experience an even day? Should I arrange
to have good things happen on even days and bad things on odd days?
I don't see how I would notice any difference.

Now, I lean more to a favorable answer to these questions. In fact I
would say, yes, I should arrange to have good things happen on even days.
Even though the difference is not directly perceptible, I believe I
would be making the universe a better place.

Here are a chain of examples. I won't try to offer much justification
at each step, I am just sketching an argument.

First, consider 10 people. We can either give 9 of them a good experience
and 1 of them a bad one, or 9 of them bad and 1 of them good. It is
clear that it is better to give the 9 good and 1 bad.

Now, consider 2 people. We are going to give the first a good experience
and the second a bad one. But we can make 9 copies of the first, or
9 copies of the second, as we do it. I claim it is better to make 9
copies of the first, the one who is having a good experience.

Now, consider a person who goes through life but who has a problem with
his short term memory that makes him forget what happens every day.
(Fictional examples can be seen in the movies Memento and Fifty First
Dates, although I don't know how realistic they are. Keep in mind this
is just a thought experiment and not dependent on any actual details of
human pathology.) We can either give him 9 days of good experiences
and 1 bad, or vice versa. I claim it is better to make the 9 days be
good experiences and 1 day bad, rather than the other way around.

And finally consider an ordinary person who remembers things from one
day to the next. On day 1 something good happens and on day 2 something
bad happens. We can either make him have 9 times the measure on day 1
or on day 2. I claim that it is better to give him 9 times the measure
on day 1, when the good thing happens.

Now, you may be saying, where is the argument? These are just examples
with unsupported claims. The point is to show that in all these examples
the people are unaware of the changes in measure and numbers of good
and bad experiences. But that doesn't change the fact that it is still
better to cause more good experiences in the world than bad.

Would we say that it is OK to mistreat a person with lack of short
term memory just because they won't remember it? I don't think so.
It still causes genuine pain and suffering. Giving them good experiences
causes joy. The 50 First Dates movie expresses this in a poignant and
moving matter. People are willing to sacrifice to bring happiness to
someone they love who suffers such a condition. I thought this was
an excellent movie BTW, although you have to overlook some extremely
juvenile humor. Memento was also interesting but much darker in tone.

It is the same with all the examples. Causing more experiences of
joy is better than causing more experiences of sadness. Even with
the one person who lives from day to day, it still applies. He is not
subjectively aware of his measure changing, but if he or anyone else has
objective awareness of the circumstance, the same logic that applies in
the other examples works here as well. Give more happiness to the days
with greater measure. That makes the world a better place.

Now for an interesting twist. Our measure decreases steadily in life.
Every day we have a certain probability of dying, and our measure
decreases by that fraction. The reasoning in the examples above would
imply that it is better to have happiness when our measure is high, which
is when we are young. Unhappiness in old age has less impact. So if
you are putting off some happiness, do it today, don't procrastinate.

(Of course, you get much the same result in a non-multiverse model,
where putting off a reward makes you risk dying before you get to
experience it.)

Hal Finney
Received on Sat May 28 2005 - 02:18:40 PDT