Re: infinity



William Hughes wrote:

Kirby Cook wrote:

William Hughes wrote:

<snip>

looks like we agree.  What I also have is the concept of the
state after all the finite steps. Call this state, state E
Which balls are in the vase at state E.
We do not know, this has to be defined.

I balk at "*all* the finite steps". Easy to say, hard to define.


You can only define state E by defining what happens at
state E.  This is done below.


Definition 1:

   Let I be the union of the sets of balls added to
   the vase at any finite step.

   Let O be the union of the sets of balls removed from
   the vase at any finite step.

   Then 0 is a subset of I and we define the set of balls
   that is in the vase at state E is the set difference I\O.


Actually, I - O, right? And that is not at E (which has yet to be defined, IMO) but at any given specific step.


I like the notation A\B for set difference rather than A-B, as the
former makes it a bit clearer that the result of a set difference is
a set, but use whatever notation you like.

Ah. Yours is OK with me.

And there is
no mistake.  I and O are defined as unions over all finite steps
and I\O (or I-O if you like) is by definition the set of balls
in the vase at state E.

I suspect we've reached an impasse. "...at any finite step" is fine; I'm with you. When you make the leap to "...over all finite steps" without so much as a by-your-leave, you lose me. <shrug> I freely admit it is due to my own lack of undestanding. Sorry.


Kirby
.



Relevant Pages

  • Re: infinity
    ... >>> Which balls are in the vase at state E. ... >>> the vase at any finite step. ... >>> that is in the vase at state E is the set difference I\O. ... A larger infinity than the infinite number that have been ...
    (sci.math)
  • Re: infinity
    ... >>> the vase keeps growing as you approach noon. ... the algorithm which describes the filling of the vase with balls ... Start with an empty vase. ... we try to connect some logical reasoning (about putting ...
    (sci.math)
  • Re: infinity
    ... the set of balls in the vase at state E ... >> consists of a finite number of sets or an infinite number of sets. ... The sum of an infinite series does depend on the number ...
    (sci.math)
  • Re: infinity
    ... by definition the vase is empty at state E. ... the set of balls in the vase at state E ... When you say "There is no change whether or not there are an infinite number of sets I_n", ... given by the sum of an infinite series. ...
    (sci.math)
  • Re: An uncountable countable set
    ... -1/n, where n is a natural number, there are balls in the vase. ... Let S be the set of naturals on balls removed before noon. ...
    (sci.math)