On 4/5/2013 11:22 AM, WM wrote: > On 5 Apr., 12:08, William Hughes <wpihug...@gmail.com> wrote: > >> More precisely. There is an infinite set of lines D >> such that any finite subset of D can be removed. > > How do you call a subset of D that has no fixed last element?
In set theory it is neither a set or a subset because the question does not make sense.
One might compare the remark to a generic set of forcing conditions described by the information content of their initial sequences. But, you would have to admit the notion of a family of initial segments that are dense within the partial order. That is contradictory to your beliefs.