On 6 Apr., 22:30, William Hughes <wpihug...@gmail.com> wrote:
> > My claim is: > > Let D be the set of all lines, and let > E be any one finite subset of D. > Then D\E is not empty.
Your claim is true. But your premise is wrong. E (the set that can be removed without changing the union of the lines) is the set of all lines that have a follower. This set of lines is infinite. By the existence of the follower to all lines, all lines, i.e., E can be removed without changing the union of all lines, namely |N.