by wendy » Thu Apr 20, 2006 7:24 am
A four-dimensional river is, like a 3d one, latrous (or line-shaped).
The ground in 3d is like a page. A line drawn across the page presents the ant something to cross.
The ground in 4d is like a room (3d), a line in the room [like a pole] presents no impediment to crossing, save if one makes a course for it.
One notes, that while railways, roads and rivers have level crossings in our world, blood, breath, and bile do not need boom-gates to controll crossings.
W