Before posting this I would like to make a reservation:
1. I'm in no way a mathematician, so don't try to start an argument after you have read the following information.
2. I just remembered the statement about converging parallel lines and found this corroboration. If it is no corroboration (to your mind) see #1.
https://en.wikipedia.org/wiki/Line_at_infinity
In projective geometry, any pair of lines always intersects at some point, but parallel lines do not intersect in the real plane. The line at infinity is added to the real plane. This completes the plane, because now parallel lines intersect at a point which lies on the line at infinity. Also, if any pair of lines intersect at a point on the line at infinity, then the pair of lines are parallel.