# Measure, Doomsday argument

```Hi everyone,

I have some questions about measure...```
```
As I understand the DA, it is based on conditionnal probabilities. To somehow
calculate the "chance" on doom soon or doom late. An observer should reason
as if he is a random observer from the "class" of observer.

The conditionnal probabilities come from the fact, that the observer find that
he is the sixty billions and something observer to be "born". Discover this
fact, this increase the probability of doom soon. The probability is
increased because if doom late is the case, the probability to find myself in
a universe where billions of billions of observer are present is greater but
I know that I'm the sixty billions and something observer.

Now I come to the measure of observer moment :
It has been said on this list, to justify we are living in "this" reality and
not in an Harry Potter like world that somehow "our" reality is simpler, has
higher measure than Whitte rabbit universe. But if I correlate this
assumption with the DA, I also should assume that it is more probable to be
in a universe with billions of billions of observer instead of this one.

How are these two cases different ?

Quentin

```