Some criticisms of the idea that the traditional method of infinite
set-subset size comparison creates experimental artifacts and is, therefore,
invalid as well as counterresponses are described below.
1. Critique: One math professor actually seemed to agree with me that the
set-subset one-to-one pairing off method actually does destroy the
relationships present in the single set. He suggested that if one wants to
maintain the intuitive result that there are one-half as many even integers
as total positive integers, ratios should be used instead of the "counting"
method (pairing off). He went on to add that while a ratio of 1:2 for the
number of evens relative to the total number of positive integers would be
found over a finite (local) interval, unfortunately, this ratio would
become undefined over the entire set because the ratio of two infinities is
undefined.
Counterresponse: I am grateful to this person for at least fully
considering my arguments instead of just saying it's different for
infinities, etc. (see below). This is far more than most people have
offered. In regard to his criticism, I would agree that the pairing off
method destroys the relationships in the single set system (the original
hypothesis) and would be happy to use ratios as he suggests. My only
disagreement is withe the view that the ratio of two infinities that start
out in the same single set is undefined. The reasoning for this is
discussed in the next section.
Is the ratio of two infinities undefined when the two infinities start out in the same single set?
My only disagreement is with the idea that the ratio of two infinities is
undefined. If the two infinities start out in separate sets, then I agree
that their ratio is undefined because there is no fixed relationship
between the elements in each set. However, if the two infinite amounts
(even integers and total positive integers) start out in the same, single,
original set where every integer has a fixed relationship with every other
integer throughout the entire infinite set and where all the integers
maintain this relationship while marching lockstep towards a single
infinite endpoint, then I would suggest that the ratio of these two
infinite amounts is not undefined. The ratio is 1:2 throughout the entire
infinite set. This is true only when the two infinite amounts start out in
a single set, which is the experimental system being studied.
2. Critique: Infinities are different/weird and don't follow the same
intuitive rules that finite sets do.
Counterresponse: It is true that infinities are different/weird, but:
A. Just saying this with no evidence to back it up is not a valid
critique. Also, evidence based on the results of the traditional
set-subset pairing off method is not valid for use in critiquing this
method.
B. While infinities are different/weird, the techniques of experimental
methodology and the scientific method should not change just because one
is studying infinities. And, one of the main principals of performing
valid experiments is that one shouldn't change the experimental system
being studied in such a way as to change the results obtained relative to
what would be obtained in the original system (in this case, the single
set of all positive integers)
3. Critique: Infinite subsets are abstract constructs (studied in the mind
only) and experimental methodology doesn't apply to mental things.
Counterresponse: Why not? If certain rules don't apply to doing thought
experiments, then the results of all thought experiments, and indeed all
reasoning of any type, are useless and invalid. Additionally, whenever
one is methodically trying to figure out what is occuring within a system,
one is performing experiments whether the system is in the "real" world or
in the mind. Furthermore, even when we do "real world" experiments, all
knowledge of these experiments is perceived in the mind and so, in a way,
even "real world" experiments are abstract constructs. Do the rules of
experimental methodology (ie, artifacts are bad) not apply to them either?
4. Critique: Infinities aren't found in nature where experiments are done, so
the rules of experimental methodology don't apply to them.
Counterresponse: I don't think it's yet determined that infinities do not
occur in nature. Our universe may be infinite in size. Space may be
infinitely divisible. Our universe may be one of an infinite number of
universes in a multiverse (multiple universe interpretations of quantum
physics). Additionally, the rules of experimental methodology should apply
to any system being studied.
Email: [email protected]
Copyright, 2001